The night sky this month

Jodrell Bank Observatory

Ian Morison tells you what can be seen in the night sky this month.

  • 24 minutes 8 seconds
    The night sky for December 2021

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during December 2021.

    The Planets

    • Jupiter As darkness falls at the start of December, Jupiter, having a magnitude of -2.29 and an angular size of 38.3 arc seconds, may be seen in the south. It transits at 17:15 GMT with an elevation of ~24 degrees. By month's end its magnitude will have reduced slightly to -2.13 and its angular size to 35.36 arc seconds and it will be seen in the south southwest at nightfall. Happily, this year Jupiter has climbed up the ecliptic somewhat so the atmosphere will not hinder our view of the solar system's giant planet as much as it has in the last two years.

    • Saturn Saturn precedes Jupiter into the sky and will be seen towards the south southwest at nightfall. It then shines with a magnitude of +0.7 with its disk 16 arc seconds across and the rings spanning some 37 arc seconds. By month's end, it has a reduced brightness of magnitude +0.71 with a 15.46 arc second disk. Sadly, its elevation will only be about 17 degrees at as December begins so the atmosphere will hinder our view of this most beautiful planet.

    • Mercury Having passed behind the Sun at the beginning of December makes an appearance after sunset in the last few days of the month very low in the southwest below Venus. It will have a magnitude of ~-0.73 and an angular size of ~6 arc seconds. Binoculars may well be needed to spot it, but please do not use them until after the Sun has set.

    • Mars This month, Mars climbs out of the Sun's glare in the pre-dawn sky having a magnitude of 1.64 on the first with an angular size of 3.77 arc seconds. It will then be best seen at around 06:41 GMT in the southeast. By month's end the best time to observe it will be at ~07:00 GMT when it magnitude will have increased slightly to 1.54 with an angular size of 4 degrees. Binoculars may well be needed, but please do not use them after the Sun has risen.

    • Venus At the start of December, Venus, at magnitude -4.87 and having an angular size of ~39 arc seconds, will only have an elevation of ~8 degrees at sunset looking towards the south southwest. It may well be lost in the Sun's glare until around 16:00. During the month it falls back towards the Sun and will be lost in the Sun's glare. As the ecliptic is at a shallow angle to the horizon in the latter part of the year, it has never got to a high evening elevation during this apparation.

    Highlights of the Month

    • December, evening: the Double Cluster and the 'Demon Star', Algol. This month is a good time to look high in the southeast towards the constellations of Cassiopea and Perseus. Perseus contains two interesting objects; the Double Cluster between the two constellations and Algol the 'Demon Star'. Algol in an eclipsing binary system as seen in the diagram below. Normally the pair has a steady magnitude of 2.2 but every 2.86 days this briefly drops to magnitude 3.4.

    • December: find M31 - The Andromeda Galaxy - and perhaps M33 in Triangulum. In the late evenings when the Moon is not prominent, the galaxy M31 in Andromeda will be visible high in the southeast. The chart provides two ways of finding it:Around new Moon (3rd December) - and away from towns and cities - you may also be able to spot M33, the third largest galaxy after M31 and our own galaxy in our Local Group of galaxies. It is a face on spiral and its surface brightness is pretty low so a dark, transparent sky will be needed to spot it using binoculars (8x40 or, preferably, 10x50). Follow the two stars back from M31 and continue in the same direction sweeping slowly as you go. It looks like a piece of tissue paper stuck on the sky just a bit brighter than the sky background. Good Hunting!

    • December - still worth observing Jupiter. This is still not a bad month to observe Jupiter which will be visible in the south after sunset. It lies in the southern part of the ecliptic and, sadly, will only reach an elevations of ~22 degrees when crossing the meridian. An interesting observation is that the Great Red Spot appears to be diminishing in size. At the beginning of the last century it spanned 40,000 km across but now appears to be only ~16,500 km across - less than half the size. It used to be said that 3 Earths could fit within it, but now it is only one. The shrinking rate appears to be accelerating and observations indicate that it is now reducing in size by ~580 miles per year. Will it eventually disappear? The features seen in the Jovian atmosphere have been changing quite significantly over the last few years - for a while the South Equatorial Belt vanished completely (as seen in Damian's image) but has now returned to its normal wide state. The diagram on right shows the main Jovian features as imaged by the author at the beginning of December 2012.

    • December: find Uranus. This month is a still a good time to find the planet Uranus in the late evening as it reached opposition on November 4th. With a magnitude of 5.7, binoculars will easily spot it and, from a really dark site, it might even be visible to the unaided eye. A medium aperture telescope will reveal Uranus's 3.7 arc second wide disk showing its turquoise colour. It lies in Aries, close to the boarder of Cetus as shown on the chart. A highlight below shows when it lies just above the Moon so making it easy to find.

    • December 6th - after sunset: Three Planets and a crescent Moon. If clear after sunset on the 6th, there will be lovely line up of Jupiter, Saturn and Venus along with a very thin crescent Moon. Binoculars may well be needed to cut through the Sun's glare, but please do not use them until after the Sun has set.

    • December 8th after sunset: - Jupiter, Saturn and the Moon. If clear after sunset on the 6th, one could observe the Moon lying below Jupiter and Saturn.

    • December 14th - evening: - Uranus above the Moon. If clear in the evening of the 14th, Uranus could be spotted lying up to the left of the Moon.

    • December 16th - late evening: the Moon below the Hyades and Pleiades Cluster. If clear in the late evening of the 16th, the Moon will be seen to lie just below the Hyades and Pleiades clusters.

    • December 22nd/23rd - late evenings: the Ursid Meteor Shower. The late evenings of the 22nd and 23rd of December are when the Ursid meteor shower will be at its best - though the peak rate of ~10-15 meteors per hour is not that great. This year, the Moon will be moving towards third quarter so, sadly, its light will hinder our view. The radiant lies close to the star Kochab in Ursa Minor (hence their name), so look northwards at a high elevation. Occasionally, there can be a far higher rate so it is worth having a look should it be clear.

    • December 31st - before dawn: Mars and the Moon. If clear and given a low horizon towards the southeast, Mars should be visible down to the left of a very thin waning crescent Moon.

    • December - Evenings of the 12th and 26th: The Straight Wall. The Straight Wall, or Rupes Recta, is best observed either 1 or 2 days after First Quarter or a day or so before Third Quarter. To honest, it is not really a wall but a gentle scarp - as Sir Patrick has said "Neither is it a wall nor is it straight!"

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during December 2021.

    In the southern hemisphere it is summertime but everything else is the same, we too are preparing for Christmas and to celebrate the anniversary of Apollo 8 - the first people to ever go around the Moon on Christmas Day 1968.

    Speaking about the Moon, this month, the New Moon is on the 4th of December - this is when it is great to go deep-sky observing. First quarter is on the 11th of December - which means the Moon is in the sky in the first part of the night, and is setting after midnight. Full Moon occurs on the 19th of December - we hope you like long walks under the moonlight, because no deep sky objects will be easily visible in the sky as full Moon does make light pollution, and you will use a moon filter if you want to observe the Moon. And finally last quarter on the 27 of December, which means the Moon is in the sky in the last part of the night so rising after midnight. This is very helpful to plan your stargazing accordingly.

    Venus, Saturn and Jupiter are beautifully aligned at sunset and visible at the beginning of the month just after sunset. Venus is the closest to the horizon followed by Saturn and then Jupiter. Towards the end of the month, Venus will get too close to the Sun, Neptune and Uranus are visible all night long. Mars is in Libra and moving into Scorpius by the end of the month, which means it will be visible in the morning sky then.

    I often get comments like, who can remember oh, so many stars, or is it really hard to remember all those constellations and so on. While this is true, many cultures - we all know that, invented stories about different stars in the sky and that made things easier to remember. Some cultures, in particular, had seasonal asterisms, and some of these asterisms encompassed the entire sky. How to remember all of it? Is by linking to things that are memorable or make your own stories!

    With that in mind, let’s look at the sky in December in New Zealand.

    December is very famous for Christmas and Christmas is very famous for Christmas trees. As I was learning the south celestial night sky, one night it occurred to me that right now in December, the entire region of the south celestial pole looks like a giant Christmas tree. Of course I am biased, and I love Christmas trees as well, but this trick helped me remember where everything was. Let’s look at that patch of the sky.

    The sky looks like a Christmas tree only in December, just after sunset, if you look at the southern part of the sky. I will start at the top with Achernar, we can give that magical tree topper function.

    Is very high in the sky about 75 degrees from the horizon. Then, just a bit lower down, the Magellanic Clouds are like two patches of snow one third town the tree and at the base, Look under the Southern Cross, those two stars, Gamma Centauri (Muhlifain) and Delta Centauri, together with the Southern Cross and Musca are the trunk.

    All the other stars in Centaurus and Vela are decorations on the lower branches. Can you see the giant celestial Christmas tree? We might not have snow this time of the year in the Southern Hemisphere but it is like nature compensated for that with a celestial Christmas Tree just in time for Christmas.

    Then, in the North, the Great Square of Pegasus – is the only horse that looks like a square and one of the very few northern constellations that is not upside-down.

    Pegasus pulls a sleigh – we can make that up out of the Pleiades, Hyades and Orion. Draw a line between these asterisms and you can see the sleigh. Orion is the back of the sleigh where the driver sits and the Pleiades is the front where the runners are curved. Can you see the sleigh? We don’t have reindeers in New Zealand so Pegasus the flying horse will have to do.

    Running behind the sleigh, on the ground , is a Dog - this is the Dog Star, Sirius. He’s very happy on the snowy road, which is the Milky Way. We can imagine that the sleigh has just come up from behind the Christmas tree and is flying across the sky to the Northern Hemisphere. But there’s one more star, my favourite star here, Canopus. I call this the Cat Star as every Sirius astronomer in New Zealand who wants a cat should contemplate this name first.

    Halfway through from the top of the Christmas tree which is the star Achernar, our cat, Canopus jumps to catch the back of the sleigh. By the looks of it, it will probably land on the dog.

    So we can turn the night sky in December, in New Zealand into a big Christmas Scene. We have a horse, sleigh, and a big Christmas Tree.

    Draw a line from Sirius to Canopus – which are two very bright stars, it will lead you to the Magellanic Clouds. Sirius is in fact the brightest star in the sky, Canopus is the second brightest star in the sky and to the right of the imaginary Christmas Tree is Alpha Centauri, the third brightest star in the sky.

    Lower on the Northern horizon, underneath the galloping hind-legs of Pegasus, Andromeda Galaxy is a smidge of light. It is the furthest object we can see with the naked eye, 2.5 million light years distance from us. When the light that we see now from Andromeda left the galaxy, on Earth, some of our hominid ancestors, facing food shortages, developed larger brains, as an evolutionary strategy. This led to the genus Homo, which first arose 2.5 million years ago. Homo habilis developed as the ice ages began, a time known as Pleistocene. And who knows, maybe the first human memories of winter too.

    Some cool binocular objects this month lay low around the horizon. Best objects to start with are obviously the Moon, the planets and double Stars (Alpha Centauri, Gamma Velorum, Beta Muscae and Upsilon Carinae, The Pleiades and Andromeda Galaxy are all great binocular targets. Then, of course, the Magellanic Clouds are great to look at. Some favourites of ours are visible in the night sky in December. The first of these is M74 which is vey hard to see due to its very low surface brightness. With very dark skies it can be seen from the Wairarapa, you’d need Bortle Scale 2 or 1 to see it. Luckily it’s not all bad for galaxy hunting in December as not too far from M74 is the bright galaxy of M77 – also known as Cetus A. This one is easy to spot even from central Wellington. We won’t see the faint outer regions of the spiral arms but the bright active core is very visible and at 33 Million light years distant the photons from this object have spent a long time making their way to Wellington.

    We do have some very impressive galaxies in the Southern Sky. One of these is NGC 253 – also known as the Sculptor Galaxy. This is a large spiral galaxy at an angle to us so it looks like an elongated ellipse. It’s relatively bright and easy to spot if you’ve got plenty of aperture. You’ll have to put your light bucket on the back of your scooter and head to a dark sky location to make out much detail, but if you do, you’ll be in for a treat as you take in the complex shapes and clumps of detail visible on the disk. Sculptor is about 12 million light years away and appears about 27 arc minutes long so is quite big.

    Quite close to Sculptor is the tight spiral galaxy known as NGC 300. This is a great galaxy to view as it’s quite close at only 6.6 million light years – for Northern Sky observers it’s a bit like a mini M33. Viewing from Wellington will show the bright core but you’ll have to head to the hills to get any detail out of the spiral arms. Keen astrophotographers will have a better time in Wellington as this galaxy is bright enough to burn through the light pollution and produce quite a nice picture.

    The problem with viewing galaxies is that they don’t really look anything like the beautiful photographs people take. They are often just a faint grey smudge in the eyepiece and you have to use your best visual observing skills to get any detail out of what you’re looking at. This is when it’s great to swing the telescope around to the majestic brilliance of the likes of the Tarantula Nebula. This gives you a picture in the eyepiece very similar to what photographers capture, just not in colour. This big giant bright complex of gas clouds and massive stars looks a bit like a spider, hence its name and it is a must see of the Southern Sky and is almost compulsory viewing on any observing evening.

    At this time of the year the two galaxy groups of the Fornax Cluster and the Grus Quartet are also in a good position for viewing. As the month advances the position of the Fornax Cluster improves and the position of the Grus Quartet gets worse so get in early to see these four stunning galaxies. Both groups are between 60 Mly and 80 Mly distant with the Grus Quartet being three galaxies visually quite close to each other and another galaxy a little further away. With the right eyepiece you can get all four in the same field of view. With the Fornax Cluster it is possible to get up to 11 galaxies at once in the same field of view. These are mainly elliptical galaxies including the stunning Fornax A.

    December in the Southern Hemisphere is generally the unhappy month for the astronomer, unless your thing is solar astronomy, because the nights are short and the temperatures are creeping up. It seems to take forever for the night to get truly dark and forever for the telescope to cool down. Unlike the rest of the population, us astronomers are craving a cold front to blow through and give us a nice cool patch of air to settle the thermals and give us some great seeing. The good news is that this time of year is perfect for an all nighter of astronomy (all 4.5 hours of astronomical night) as the Milky Way passes through the zenith in the early hours and there’s a wealth of deep sky objects to fill your eye piece.

    Due East – Taurus Orion region

    A good place to start an evening’s viewing is Orion, that majestic constellation that is easy to find in the Northeast at about 35 degrees in elevation. With a pair of binoculars an observer can easily see the Great Orion Nebula (Messier 42 or M42) which is a huge star forming region just above Orion’s Belt, which is made up of the three stars of Alnitak, Alnilam and Mintaka. Mintaka is very dear to navigators as it’s located exactly on the celestial equator.

    Orion has a number of very interesting stars including Betelgeuse which is a red supergiant and one of the largest stars in the sky. It is one of the few stars that have been imaged and it’s unusual shape is quite apparent showing it probably has a very unstable atmosphere causing the asymmetric bulging of the star. Because of its massive size Betelgeuse will not live for much longer – maybe only another 1000 years. Or it may have already exploded! But given its 400 or so light years away we might not find out for a while. When it does go it will create quite a spectacle on Earth as it will be a very bright supernova and will probably even be visible in daylight.

    M42 is relatively close to us at about 1400 light years which makes it one of the brightest nebulae in the sky. With a telescope the M42 can appear to have a greenish tint, unlike the bright red photos that are often published. It is estimated that M42 is about 24 light years across and that it is part of a much larger structure known as the Orion Molecular Cloud, which extends for about 10 degrees across the whole constellation of Orion. This cloud includes the famous Horse Head Nebula (B33), Flame Nebula (NGC 2024), M78 and Barnards Loop (Sharpless 2-276). If you have access to an infrared telescope, you can also see the brightest object in infrared, that is the Becklin-Neugebauer object. M42 is one of the most photographed objects due to its brightness and visibility in both the Northern and Southern Hemispheres.

    These are some of my favourite things about December, other than sleigh bells and snowflakes and warm woolen mittens and from here from New Zealand,

    I wish you clear skies so that you can always see the stars and always remember we are made of the same star dust as they are.

    18 December 2021, 4:00 pm
  • 27 minutes 1 second
    The night sky for May 2021

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during May 2021.

    The Planets

    • Jupiter: As May begins and given a low horizon towards the southeast, Jupiter, rising at 03:36 BST around 2 hours before the Sun, may be glimpsed just before dawn shining at magnitude -2.2 and having an angular size of 37.44 arc seconds. By month's end, it rises at 01:43 BST, about three hours before the Sun, when its magnitude will have increased slightly to -2.4 and its angular size to 41.2 arc seconds. Sadly, its low elevation of ~20 degrees as dawn approaches will somewhat hinder our view of the solar system's giant planet.
    • Saturn: Saturn precedes Jupiter into the sky, rising at ~03:00 BST at the beginning of the month. A low horizon towards the south-east will be needed to see them both. It is then shining with a magnitude of +0.71 and its disk is 16.7 arc seconds across with the rings spanning some 39 arc seconds. By month's end, it rises at 01:00 BST with a slightly increased brightness of magnitude +0.57 and a 17.6 arc second disk. We will have to wait a while to see this most beautiful planet at its best.
    • Mercury: This month Mercury has its best evening apparition of the year. The planet is at its brightest, at magnitude-1, at the start of May. It then lies just below the Pleiades cluster in Taurus having an angular size of ~6 arc seconds. From the 3rd to the 6th it lies within a binocular field of view of 2.8 magnitude Alcyone in the cluster's centre. Its greatest elongation east is on the 17th when it stands about 11 degrees above the north-western horizon around 45 minutes after sunset. It will then have a magnitude of +0.41 and an angular diameter of just over 8 arc seconds. It then falls back towards the horizon passing very close to Venus on the 28th.
    • Mars: Mars passed into Gemini on the 23rd of April and starts the month with a magnitude +1.56 It will be best seen in the west at an elevation of ~24 degrees soon after nightfall. Reducing in brightness to +1.74 by month's end, it will still be visible in the evening sky until August before it passes behind the Sun in October.
    • Venus: At the start of May Venus, at magnitude -3.88 and having an angular size of ~10 arc seconds, will only have an elevation of ~6 degrees at sunset towards the northwest. By month's end, its elevation at sunset will have increased to ~11 degrees and its magnitude reduced very slightly to -3.85. Venus will grace the evening sky for the rest of this year and reaches its greatest elongation east from the Sun on October the 29th but will be highest in the evening sky at the beginning of December.

    Highlights of the Month

    • May 13th - after sunset: Mercury and a thin crescent Moon: If clear this evening, Mercury will be seen up to the right of a very thin crescent Moon. One might also spot Venus down to the right of the Moon.
    • May 13th - early evening: Mars and a thin crescent Moon: If clear this evening, Mars will be seen up to the left of a thin crescent Moon. One might also be able to spot Mercury down to the right of the Moon.
    • May26th - late evening: A supermoon: On the night of the 26th, the Moon will be at Perigee - its closet point to the Earth - and its angular size will be 33.6 arc minutes across compared to its average diameter at full moon of 31 arc minutes - so 8% larger in diameter. As the Moon is then as bright as it can ever be, it is called a 'supermoon'. Sadly, due to Covid, one could not now fly to New Zealand or Eastern Australia where at ~11:19 UT a brief total eclipse of the Moon could be seen.
    • May28th - after sunset: Venus and Mercury: After sunset on the 28th, if clear, one would be able to see Mercury (at magnitude 2.3) around half a degree away from Venus some 300 times brighter. Mercury presents a tiny crescent but Venus a nearly full disk - with both being around 10 arc seconds across.
    • May 31st - before dawn: Jupiter, Saturn and a thin crescent Moon: Before dawn on the 31st, low in the southeast, Jupiter, over to the left, and Saturn, above, a very thin crescent Moon.
    • May 2nd and 18th, evening: The Hyginus Rille: These evenings, should it be clear, are a superb time to view the Hyginus Rille as it will lie close to the terminator. For some time a debate raged as to whether the craters on the Moon were caused by impacts or volcanic activity. We now know that virtually all were caused by impact, but it is thought that the Hyginus crater that lies at the centre of the Hyginus Rille may well be volcanic in origin. It is an 11 km wide rimless pit - in contast to impact craters which have raised rims - and its close association with the rille of the same name associates it with internal lunar events. It can quite easily be seen to be surrounded by dark material. It is thought that an explosive release of dust and gas created a vacant space below so that the overlying surface collapsed into it so forming the crater.

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during May 2021.

    Kia Ora from New Zealand, this is Haritina Mogosanu And Samuel Leske from Wellington New Zealand, we are here with the night sky in May 2021.

    If we look at the night sky long enough to observe changes in the patterns of stars, we notice that these patterns shift ever so slowly westwards. The reason for that is our vantage point from where we are looking at the stars behind our Solar System, our galactic immediate neighbours, that vantage point changes every day by about one degree. From Earth, it seems like the same stars come up every day about 4 minutes earlier. But that’s not true for all stars. There are some stars that in New Zealand, never set or rise, their light just gets washed away by the Sun when it rises. These stars move around in circles and we call them circumpolar. The point that is visible from New Zealand around which stars rotate is called the South Celestial Pole. There are some stars that we never see from New Zealand, such as Polaris, the North Star, most of the big dipper stars, Casiopeea and so on, we don’t see them here because they are hidden by the Earth.

    So if you ever buy a star and you wish to observe it, here’s something you need to keep in mind. Do you travel much around the Earth? Because except if you are on the equator, where if you are patient and can spare a few months waiting then you can see most of the stars in ideal conditions (I am accounting here for stars that are too low on the horizon) then everywhere else on Earth there are places where you see some stars and some you don’t. And if you decide to move at one of the poles forever, then every night you will see all the stars in your half of the sky and you will never see the other half.

    So when we talk about what is in the sky in New Zealand, there are stars that are always in the sky here, these are the circumpolar stars. The bulk of them make a beautiful big circle in the southern part of the sky. The most famous of them is the Southern Cross and the two pointers, beautiful and bright, located straight in the Milky Way. If you ever get lost in New Zealand and you can see the Milky Way, just follow that and somewhere along the way is the Southern Cross. This works anytime on a clear sky night from a dark sky location (which is about 80% of New Zealand by the way). This time of the year, after sunset, the Southern Cross is up high, which means it is in a good position to observe. Around the Southern Cross is the famous asterism, invented by a bunch of Christchurch kids, of The Frying Pan. The two pointer stars are the handle of the frying pan and the stars in Centaurus that surround it are the pan. The southern cross, they said, is the Fish in the Frying Pan. Maori call the dark patch, the Coalsack around the Southern Cross, they call it the Flounder.

    An asterism, just like a constellation, means a grouping of stars, but the word constellation is used now for the official sectors in the sky so to describe everything else that is unofficial asterism is the better definition. If you want to make the asterism of The Wok instead of a frying pan, we use the amazing Omega Centauri globular cluster as the pointy bottom of The Wok. Omega Centauri is also in a good position to observe this time of the year, finally!

    First identified as a non-stellar object by astronomer Edmond Halley in 1677, Omega Centauri is about 5000 parsecs or 17 thousand light years away from us, and is the most massive globular cluster in the Milky Way, with a diameter of 150 light years across. It has about 10 million stars, weighing almost as much as the supermassive black hole at the centre of the Milky Way, that is about 4 million times more massive than our Sun. Omega Centauri is visible with the naked eye, in binoculars and in a telescope, the bigger the better the view. It is spectacular. What makes it very special other than it’s lace appearance and size is that at it’s centre, Omega Centauri has its own black hole, and it is believed it might have originally been a dwarf galaxy just like the Magellanic Clouds that was eaten by the Milky Way.

    Following the Milky Way, in the constellation Carina there is a hypergiant star, Eta Carinae. Eta Carinae is about 2,300 parsecs or seven and a half thousand light years away. It has at least two stars of a combined luminosity five million times greater than the Sun. For three days in 1843 it became the second brightest stars in the sky, brighter than Canopus (officially the second brightest star in the sky) then faded away so it could not be seen with the naked eye and finally now has come back to being visible and is around magnitude 4-4.3, which means it can be seen with the naked eye if you know where to look. Better though, in a telescope Eta Carinae is spectacular, it has an orange tinge and there are beautiful nebulae surrounding it, it’s one of my favourite telescope objects in the entire night sky. Eta Carinae nebula is also home to WR25, one of the most luminous stars known in our galaxy.

    Two open clusters, both great in binoculars but even better in telescopes are nearby the Southern Cross, these are the Jewel Box (on the same side with the pointers) and the Pearl Cluster (NGC 3766), on the opposite side. They are both really beautiful open clusters of stars and you can see blue and red giants in those clusters when you look at them through the telescopes. Pearl Cluster is also very close to Lambda Centauri that is home of the Running Chicken nebula, which is only a good object for astrophotography as it’s very hard to see otherwise.

    Right by the Diamond Cross, a good binocular object is the Southern Pleiades. These are also very high in the sky, and good that they are because the Northern Pleiades, also known as the Pleiades are now very close to the Sun and so we can’t see them for a couple of months.

    And finally, by the False Cross, in Vela, the Omicron Velorum star cluster or IC 2391 only about 500 light years from Earth and NGC 2516 are also objects we look at on a regular basis, every weekend, this time of the year. NGC 2516 is also known as the Southern Beehive - because it is thought it resembles the real Beehive cluster M44. This proves once again, Sam’s point that astronomers are really really good at naming stars.

    The two neighbouring galaxies, the Large and Small Magellanic clouds are now a bit harder to observe because they are in the lower third each side of the axis that goes from the Southern Cross to Achernar - also a circumpolar star. After sunset of course, the Large Magellanic cloud is the patch to the west and the Small Magellanic Cloud is the patch to the east of that axis. Just pick up a pair of binoculars and enjoy them. They are not so much visible with the naked eye as you would expect so we always use peripheral or averted vision to see them better. From Wellington’s botanical gardens or on a full Moon night, you can just barely see them. Now because they are lower onto the horizon, we are observing them through a layer of atmosphere which is okay for visual observations but not good for deep sky astrophotography.

    As the Earth orbits the Sun, it also spins on its axis. The extension of this axis to infinity gives us the South Celestial Pole and the North Celestial Pole. The height of the celestial pole in the sky gives you the latitude that you are on Earth. The lower the Celestial Pole in the sky, the smaller the circumpolar region and the other way around. In New Zealand, the South Celestial Pole is at approximately 40 degrees in the sky, which is also the radius of the circumpolar zone. Canopus is also circumpolar and is in the sky here all night long.

    The circumpolar stars are always in the sky and depending on how much moisture is there in the sky from your observing place or how much light pollution you can enjoy very many of these objects all year long and all night long.

    The circumpolar zone is fascinating, if you have one, you can almost learn to use it as a clock for time keeping. The stars rotate in 23 hours and 56 minutes so every day they shift a bit. The ancient Egyptians called these stars “indestructible” (never go away) and aligned their pyramids and temples with them. They also believed their pharaohs became stars of the circumpolar region after they died so by aligning the pyramids to the Pole star the souls of the dead had direct passage north Unfortunately we cannot see those pharaoh that became stars from New Zealand as it just so happens the North Circumpolar Region is hiding right behind Earth as observed from here.

    While the Ancient Egyptians saw circumpolar stars "Ikhemw-sek" as indestructible and imperishable they thought that the rest of the stars were "Ikhemw-wredj" unwearying. Kondo. This is alluding to the fact that even though they had a longer path to travel than the circumpolar stars, the other stars still kept coming back up from behind the horizon.

    The other part of the sky that we see from New Zealand is seasonal. There’s a new book by famous archaeoastronomer Professor Anthony Aveni called Star Stories, where he discusses seasonality as a common theme among constellation myths. Stories progress as constellations move across the sky, he says, — It’s all about the stories and what we learn from them. “We created constellations for discourse about moral issues and social rules, about affairs both practical and spiritual, about our immediate needs and our wildest dreams” The sky is there to tell tales of moral significance for all of the cultures, he says.

    Here in New Zealand, Maori, have even different names and stories for the same stars as they shift across the sky each season occupying a different position as seen after sunset, in regards to the cardinal points.

    The most popular of these seasonal constellations are the zodiacal constellations. The stars that make the zodiacal constellations are those stars that are behind the path of the planets in our solar system. Nobody knows for sure who invented them or what they looked like in ancient times but we do know the Summerians left a rich artistic tradition that showed many naturalistic animals but featured prominently lions, bulls and sometimes scorpions. These same animals were pictured in the sky as the earliest zodiacal constellations: Taurus, Leo and Scorpius. (Rogers). Their stars are 3 of the 4 the Royal Stars: Aldebaran in Taurus, Regulus in Leo and Antares in Scorpius. What’s awesome about these constellations is that they are about 90 degrees apart from each other. A fourth constellation that completes the four Mesopotamian pillars of the sky is Aquarius (now set).

    This time of the year,after sunset, we can see the constellation of Leo in the mid northern part of the sky while Scorpius is rising from the west.

    Gemini is lying along the horizon waiting to set so not in a good position to observe.

    Leo is an amazing target for telescopes and binoculars. Close to the area south of the triangle that marks Leo’s hips…M65, M66 and NGC 3628, which will be visible depending on the size of your binoculars they are also known as the “Leo Triplet”. Also in Leo, M105 is an elliptical galaxy. M96 another galaxy in Leo lies at about 35 million light years away.

    To the east of Leo is Virgo, home of the 3C 273 quasar, which is a favourite observation target for us.

    To the east of Virgo is Libra the scale, reinvented by the ancients by reducing the claws of the scorpion to mark the autumnal equinox when the days were equal to the nights. Hence Libra is a symbol of equality and justice. Due to precession, the equinox now occurs in Virgo. Ironically, the two brightest stars in Libra still bear the names of Northern Claw and Southern Claw, Zubenelgenubi and Zubeneschamali, a reminder of the former glory of Scorpius.

    In May, we have more hours of dark than we have of light. If you are a morning bird you must wait until 7 AM for the sunrise at the beginning of the month and 7:30 at the end of the month. If you are a stargazer, then be happy, as sunset is very early in May, the Sun is going down at about 5:30 at the beginning of the month and around 5 at the end of the month. But that’s not when the darkness falls onto New Zealand, it would take two more hours for it to be well enough beyond the horizon - which is when it is officially night. So only two hours later you should be able to properly see /photograph some deep sky objects, that is if you are lucky enough to have a moonless night.

    Speaking of which, here is what happens to the Moon in May:

    At New Moon, the Moon rises and sets with the Sun - so is on the same line of sight as the Sun.

    The next traditional phase of the Moon is the First Quarter, in May this occurs on the 20th And last but not least Full Moon is on 26 th of May. Just a note, the worst time to look at the Moon through a telescope is at Full Moon. The Moon is really bright as it has the maximum amount of surface lit from the Sun, remember the Moon reflects the light from the Sun so unless you have a Moon filter it will be a strain for the eye. If you look at it through a telescope you will lose the little dark adaptation you got throughout the night. However, the Full Moon is great to photograph through a small telescope with a normal phone camera - held by an adaptor of course or even by your hand.

    No naked eye planet is visible in the evening sky but if you wait until after midnight, you will see Saturn and Jupiter and in the morning, just before sunrise they are the two bright objects in the northwestern sky.

    Before we sign out, the constellation featured by Globe at Night in May is Crux. Get your observing hat on and help us measure light pollution around the world. You will see detailed instructions on our website, Look after our Night Sky, or on GlobeAtNight.org. All you have to do is count the number of stars you can measure from your street and compare these with the number of stars from Globe at Night’s maps. This is a citizen science project where anyone can participate and make a difference while you learn your stars.

    21 May 2021, 5:30 pm
  • 17 minutes 53 seconds
    The night sky for December 2020

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during December 2020.

    The Planets

    • Jupiter, along with Saturn, still remains visible, low in the sky, west of south when darkness falls as December begins and sets around 19:00 GMT. Towards the end of the month it will be seen towards the southwest after sunset and sets by ~17:30 GMT. Its magnitude remains at -2.0 during the month whilst its angular diameter falls from 34.4 to 32.9 arc seconds. Sadly, even when first seen after sunset, it will only have an elevation of ~12 degrees above the horizon so the atmosphere will limit our views. Due its position in the most southerly part of the ecliptic this has been a very poor apparition for those of us in the northern hemisphere.

    • SaturnClosely follows Jupiter into the sky, some 2 degrees behind at the start of the month but reducing to just 6 arc minutes on the evening of the 21st! [See highlight above.] Saturn is best seen in the south just after sunset on the 1st. Its magnitude remains steady at +0.6 whilst its angular size decreases from 15.7 to 15.3 arc seconds. The rings span some 35 arc seconds across and, at ~22 degrees to the line of sight, show up well. Saturn starts the month in Sagittarius and moves into Capricornus on the 15th. Sadly again, its low elevation of ~12 degrees when first visible in the evening will limit our views of this most beautiful planet.

    • Mercury will be visible using binoculars very low in the southeast at dawn for the first few days of the month. On the first, it rises only 45 minutes before the Sun shining at magnitude -0.8. It will pass through superior conjunction (closest to the Earth) on the 20th of the month. Please do not use binoculars after the Sun has risen.

    • Venus, rises in the southeast some 2 hours before the Sun at the star of December but by half an hour less by month's end. Its magnitude remains at -3.9 throughout the month whilst its angular size reduces from 11.7 to 10,7 arc seconds. At the same time its phase, the percentage illuminated disk, increases from 89% to 94% which explains why its magnitude remains constant.

    Highlights of the Month

    Early December - still a good time to view Mars.This is still a good month to observe Mars which had its closest approach to Earth back on October the 6th when it will lay 39 million miles from Earth and reached opposition on the 13th. Wonderfully, at this opposition, Mars has been far higher in the sky than at recent oppositions. In Pisces, Mars, shining at a magnitude of -1.1 at the start of the month, can be seen crossing the meridian at 20:30 GMT. By month's end it magnitude will have dropped to -0.3 whilst being due south at ~19:15 GMT. Its angular size is just over 14 arc seconds at the start of the month dropping to 10.5 arc seconds by month's end. Reaching an elevation of ~45 degrees when due south as seen from the UK, amateur telescopes will enable one to see features, such as Syrtis Major, on its surface when the seeing conditions are good.

    During this apparition, Mar's southern hemisphere is tipped towards the Earth and so the South Polar Cap should be visible, though much of its frozen carbon dioxide will have vaporised during the Martian summer. Though the North Polar Cap is beyond our view, one should be able to spot the haze of the North Polar Hood lying above the northern limb of the planet. At 24.6 hours long, the Martian day is similar to ours, so the surface details remain similar at the same time each night. Mars takes 41 days to make an apparent rotation as seen from Earth.

    December 14th and 15th after midnight: the Geminid Meteor Shower.The early mornings of December 14th and 15th will give us the chance, if clear, of observing the peak of the Geminid meteor shower. The Moon is new so, pleasingly, its light will not hinder our view. The Geminids can often produce near-fireballs and so the shower is well worth observing if its clear. An observing location well away from towns or cities will pay dividends. The relatively slow moving meteors arise from debris released from the asteroid 3200 Phaethon. This is unusual, as most meteor showers come from comets. The radiant - where the meteors appear to come from - is close to the bright star Castor in the constellation Gemini as shown on the chart. If it is clear it will be cold - so wrap up well, wear a woolly hat and have some hot drinks with you.

    December 21st - after sunset - The closest visible conjunction of Jupiter and Saturn since 1226!After sunset on the 21st of December, let us hope for clear skies as Saturn and Jupiter will be at their closest in the sky since the middle ages at just 6 arc minutes apart! This means that with a telescope at moderate power one would be able to encompass both planets and their brighter satellites; Io Europa, Ganymede and Callisto with Jupiter and Titan with Saturn.

    December 22nd/23rd - late evenings: the Ursid Meteor ShowerThe late evenings of the 22nd and 23rd of December are when the Ursid meteor shower will be at its best - though the peak rate of ~10-15 meteors per hour is not that great. Pleasingly, this year the first quarter Moon Moon will set around midnight so its light will not greatly hinder our view. The radiant lies close to the star Kochab in Ursa Minor (hence their name), so look northwards at a high elevation. Occasionally, there can be a far higher rate so its worth having a look should it be clear.

    December - evening: the Double Cluster and the 'Demon Star', Algol.This month, in the evening, is a good time to look high in the south towards the constellations of Cassiopea and Perseus. Perseus contains two interesting objects; the Double Cluster between the two constellations and Algol the 'Demon Star'. Algol in an eclipsing binary system as seen in the diagram below. Normally the pair has a steady magnitude of 2.2 but every 2.86 days this briefly drops to magnitude 3.4.

    December: find M31 - The Andromeda Galaxy - and perhaps M33 in TriangulumAround new Moon (14th December) - and away from towns and cities - you may also be able to spot M33, the third largest galaxy after M31 and our own galaxy in our Local Group of galaxies. It is a face on spiral and its surface brightness is pretty low so a dark, transparent sky will be needed to spot it using binoculars (8x40 or, preferably, 10x50). Follow the two stars back from M31 and continue in the same direction sweeping slowly as you go. It looks like a piece of tissue paper stuck on the sky just a bit brighter than the sky background. Good Hunting!

    December 12th - 1 hour before sunrise - Venus and a thin crescent Moon.Before dawn on the 12th of December, Venus will be seen, if clear, down to the lower left of a very thin crescent Moon. Look out for the 'dark' side of the Moon illuminated with light reflected from the Earth - 'Earthshine'.

    December 17th - after sunset - Jupiter, Saturn and a thin crescent MoonAfter sunset on the 17th of December, Saturn and Jupiter will be seen, if clear, to the right of a very thin crescent Moon. Look out for the 'dark' side of the Moon illuminated with light reflected from the Earth - 'Earthshine'.

    December - Evenings of the 7th and 23th: The Straight WallThe Straight Wall, or Rupes Recta, is best observed either 1 or 2 days after First Quarter or a day or so before Third Quarter. To honest, it is not really a wall but a gentle scarp - as Sir Patrick has said "Neither is it a wall nor is it straight!"

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during December 2020.

    • The evening sky in December is commandeered by the edge of our galaxy, visually in the asterisms of Orion and Taurus. The region in question is so beautiful that it simply demands all attention. However, the entire December sky is shattered with bright planets and bright stars at dusk.

      Jupiter is the brightest object after sunset, low in the west. Saturn is close to Jupiter, above and right of it at the beginning of the month. Mars is due north at dusk, still beautiful and bright. The three brightest stars in the sky are also visible at the same time: Sirius, the brightest true star is midway up the eastern sky, Canopus, the second brightest star, is high in the southeast and Alpha Centauri, the third brightest star is due south.

    • In December, Jupiter and Saturn will be very close, as they near their once-in-20-years conjunction on December 21-22nd, 2020. At their closest, they will be only 0.1 degrees apart. That’s just 1/5 of a Full Moon diameter. They will be in close visual proximity from December 17th to the 26th. When two bright objects in the sky are in the same line of sight, we call the phenomenon a conjunction. Every twenty years, Jupiter, orbiting the Sun in 12 years, catches up with Saturn, which takes 30 years to do an orbit. Of course, a conjunction is a visual illusion. In reality, Jupiter is 879 million km away and Saturn 1,610 million km away, mid-month, almost twice further away from the Sun. From Wellington, it would be a bit tricky to photograph or see the two objects through a telescope on the 21st of December but if you observe them at 9PM when it is not yet night, they will be at about 15 degrees above the horizon. Try and find a place with a clear horizon. Otherwise, they will simply be two bright dots visible in the west after sunset.

    • Another beautiful visual combination is the line that the brightest star Sirius makes with the Second brightest star, Canopus. Extend that line south and you will come across the Large and the Small Magellanic clouds. This is a very good trick to find our beautiful southern dwarf irregular galaxies in the night sky. From a dark sky, the Large Magellanic Cloud looks like a chunk of the Milky Way has been displaced nearby.

    • The Southern Cross and the pointers are very low on the Southern horizon, making the asterism of the frying pan. The two pointers are the handle of the pan, and Epsilon Centauri (Birdun), Gamma Centauri (Muhlifain) and Delta Centauri (SAO 239689) are the frying pan. The Southern Cross is the fish frying in the pan. Close to the Southern Cross, the dark region of the Coalsack for Maori is the flounder also frying in the frying pan. Our gastronomical sky also contains the Pot, in Orion, with the bottom of the pot made by the three stars of Orion’s belt and the handle of the pot constructed from the metal of Orion’s sword. The pot is held in place by Eta Orionis.

    • This is the best time of the year to observe our famous southern sky galaxies, the magellanic clouds. The first person to write about them, was the Persian Astronomer Al-Sufi around 964 AD. Explorer Amerigo Vespucci, in a letter about his third voyage around 1503 - 1504 was the next to write about the Magellanic Clouds and also about the coalsack, referring to them as the three “Canopes”, two bright and one obscure. And finally, Ferdinand Magellan wrote about it after his voyage in 1519. To spot the Magellanic clouds, you need a very dark sky and use your peripheral vision. With a telescope, the Large Magellanic Cloud is an amazing sight. One of my favourite deep sky objects, 30 Doradus or Tarantula nebula is a cloud of partially ionized gas in which star formation has recently taken place. Just like the horsehead nebula in Orion, the Tarantula Nebula in the Large Magellanic Cloud is a place where thousands of stars can form over a period of several million years. Supernova 1987a—the nearest supernova in recent years, co-discovered by New Zealand astronomer and Guinness book record holder Albert Jones, —was in the Large Magellanic Cloud. For regions like the Tarantula Nebula, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases, now easily visible in telescopes, leaving behind a cluster of stars which have formed. We can see what happened to such stars when we look at the starcluster the Pleiades.

    • Close to Zenith is Achernar from Eridanus, all the beautiful stars of Grus and Fomalhaut. In Grus, the Grus Quartet is now visible. In Sculptor, the famous Sculptor galaxy is in a good position to observe. This galaxy has a visual magnitude of about 7 and it is visible with the naked eye, it looks like a blurred star. Sculptor galaxy is about 12 million light years away from us.

    • A total solar eclipse will be visible from South America on the 15th of December as the New Moon disappears into the Sun’s glare. There will also be a few minor meteor showers, the geminids and leonids, nothing that compares with the northern Hemisphere’s perseids in August. Mercury will pass around the far side of the Sun on December 20th and on the 21st we will have the longest day of the year, the summer solstice.

    19 December 2020, 12:00 pm
  • 7 minutes 53 seconds
    The night sky for November 2020

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during November 2020.

    Highlights of the Month

    • Early November - still a good time to view Mars. This is still a great month to observe Mars which had its closest approach to Earth on October the 6th when it will lay 39 million miles from Earth and reached opposition on the 13th so the highest in the south around late evening. Wonderfully, at this opposition, Mars is far higher in the sky than at recent oppositions. In Pisces, Mars, outshining even Jupiter at the start of the month, can be seen rising in the east at sunset at the start of November. It crosses the meridian at 22:30 GMT on the 1st of the month and at 20:30 GMT by month's end. Its magnitude as November begins is -2.1 and fades to -1.2 by the end of the month. Its angular size is just over 20 arc seconds at the start of the month dropping to 14,8 arc seconds by month's end. Reaching an elevation of ~43 degrees when due south as seen from the UK, amateur telescopes will enable one to see features, such as Syrtis Major, on its surface when the seeing conditions are good. This is the best time to observe Mars until 2035!

      During this opposition, Mar's southern hemisphere is tipped towards the Earth and so the South Polar Cap should be visible, though much of its frozen carbon dioxide will have vaporised during the Martian summer. Though the North Polar Cap is beyond our view, one should be able to spot the haze of the North Polar Hood lying above the northern limb of the planet. At 24.6 hours long, the Martian day is similar to ours, so the surface details remain similar at the same time each night. Mars takes 41 days to make an apparent rotation as seen from Earth.

    • November early mornings: November Meteors. In the hours before dawn, November gives us a chance to observe meteors from two showers. The first that it is thought might produce some bright events is the Northern Taurids shower which has a broad peak of around 10 days but normally gives relatively few meteors per hour. The peak is around the 10th of November when the Moon is two days after third quarter so its light may intrude. The meteors arise from comet 2P/Encke. Its tail is especially rich in large particles and, this year, we may pass through a relatively rich band so it is possible that a number of fireballs might be observed!

      The better known November shower is the Leonids which peak on the night of the 17th/18th of the month. The Moon is just after new and will have set well before midnight so its light will not hinder our view and so enable the fainter meteors to be seen. As one might expect, the shower's radiant lies within the sickle of Leo and meteors could be spotted from the 15th to the 20th of the month. The Leonids enter the atmosphere at ~71 km/sec and this makes them somewhat challenging to photograph but it's worth trying as one might just capture a bright fireball. Up to 15 meteors an hour could be observed if near the zenith. The Leonids are famous because every 33 years a meteor storm might be observed when the parent comet, 55P/Temple-Tuttle passes close to the Sun. In 1999, 3,000 meteors were observed per hour but we are now halfway between these impressive events hence a far lower rate is expected.

    • November, evening: the Double Cluster and the 'Demon Star', Algol. This month, in the evening, is a good time to look high in the east towards the constellations of Cassiopea and Perseus. Perseus contains two interesting objects; the Double Cluster between the two constellations and Algol the 'Demon Star'. Algol in an eclipsing binary system as seen in the diagram below. Normally the pair has a steady magnitude of 2.2 but every 2.86 days this briefly drops to magnitude 3.4.

    • November: find M31 - The Andromeda Galaxy - and perhaps M33 in Triangulum. In the late evenings when the Moon is not prominent, the galaxy M31 in Andromeda will be visible high in the southeast. There are two ways of finding it:

      1) Find the square of Pegasus. Start at the top left star of the square - Alpha Andromedae - and move two stars to the left and up a bit. Then turn 90 degrees to the right, move up to one reasonably bright star and continue a similar distance in the same direction. You should easily spot M31 with binoculars and, if there is a dark sky, you can even see it with your unaided eye. The photons that are falling on your retina left Andromeda well over two million years ago!

      2) You can also find M31 by following the "arrow" made by the three rightmost bright stars of Cassiopeia down to the lower right.

      Around new Moon (15th November) - and away from towns and cities - you may also be able to spot M33, the third largest galaxy after M31 and our own galaxy in our Local Group of galaxies. It is a face on spiral and its surface brightness is pretty low so a dark, transparent sky will be needed to spot it using binoculars (8x40 or, preferably, 10x50). Follow the two stars back from M31 and continue in the same direction sweeping slowly as you go. It looks like a piece of tissue paper stuck on the sky just a bit brighter than the sky background. Good Hunting!

    • November: find Uranus. This month is a good time to find the planet Uranus in the late evening as it reached opposition on October 31st. With a magnitude of 5.7, binoculars will easily spot it and, from a really dark site, it might even be visible to the unaided eye. A medium aperture telescope will reveal Uranus's 3.7 arc second wide disk showing its turquoise colour. It lies in Aries, close to the border of Cetus as shown on the chart.

    • November 13th - 1 hour before sunrise - Venus, Mercury and Spica and a thin crescent Moon. Before dawn on the 13th of November there will be a very nice grouping of the planets Mercury and Venus along with a very thin crescent Moon and Spica, Alpha Virginis.

    • November 19th - evening: Saturn, Jupiter and a waxing crescent Moon. After sunset on the 19th of the month, a waxing crescent Moon could be seen, if clear, below Saturn and Jupiter.

    • November 22nd - before dawn : Venus, Mercury and Spica. Before dawn on the 22nd, first Venus and then Mercury will lie down to the lower left of Spica, Alpha Virginis.

    • November 25th - after sunset : Mars lies up to the left of the Moon. After sunset on the 25th, Mars will be seen above a waxing Moon between third quarter and full.

    • November 8th and 24th: The Alpine Valley. These are two good nights to observe an interesting feature on the Moon if you have a small telescope. Close to the limb is the Appenine mountain chain that marks the edge of Mare Imbrium. Towards the upper end you should see the cleft across them called the Alpine valley. It is about 7 miles wide and 79 miles long. A thin rill runs along its length which is quite a challenge to observe. The dark crater Plato will also be visible nearby. You may also see the shadow cast by the mountain Mons Piton lying not far away in Mare Imbrium. This is a very interesting region of the Moon!

    The Planets

    • Jupiter along with Saturn still remains visible, low in the sky, just west of south when darkness falls as November begins and sets around 20:30 pm GMT. Towards the end of the month it will be seen towards the southwest after sunset and sets by ~19:00 pm GMT. Its magnitude dims slightly from -2.2 to -2.0 during the month whilst its angular diameter falls from 37.0 to 34.5 arc seconds. Sadly, even when first seen after sunset, it will only have an elevation of ~14 degrees above the horizon so the atmosphere will limit our views. Due its position in the most southerly part of the ecliptic this has been a very poor opposition for those of us in the northern hemisphere.

    • Saturn. Following Jupiter into the sky, some 5.1 degrees behind at the start of the month but reducing to just 2.3 degrees by month's end, Saturn is best seen in the south just after sunset on the 1st. Its magnitude remains steady at +0.6 whilst its angular size decreases from 16.3 to 15.7 arc seconds. The rings span some 35 arc seconds across and, at ~22 degrees to the line of sight, show up well. Saturn lies in Sagittarius near the border of Capricornus. As the year progresses, Saturn becomes closer to Jupiter until, on the 21st December they are just 0.1 degrees apart. Sadly again, its low elevation of ~16 degrees when crossing the meridian will somewhat limit our views of this most beautiful planet.

    • Mercury is visible all month in the pre-dawn sky, shining initially with a magnitude of +1.6 and rises over an hour before the Sun when its 21% illuminated disk has a diameter of 8.6 arc seconds. As the month progresses, its apparent size decreases to 5 arc seconds but, as its phase (the percentage illuminated disk) has increased from 14% to 95%, its magnitude actually increases to -0.7. Mercury reaches greatest elongation west on the 10th of November shining at magnitude -0.6 and still rises an hour before the Sun by month's end.

    • Mars: See highlight above.

    • Venus still dominates the pre-dawn sky rising around three hours before sunrise as November begins and half an hour less by month's end. It shines at magnitude -4 as November begins, dropping fractionally to -3.9 by the 11th for the remainder of the month whilst its angular size shrinks from 13.1 to 11.7 arc seconds. During the same time its phase (the illuminated percentage of the disk) increases from 81% to 88% which is why the fall in magnitude is so small. It still reaches an elevation of ~21 degrees at sunrise at the start of the month. For the majority of the month, Venus lies in Virgo but moves into Libra on the 23rd.

    The Stars

    • The November Sky in the south - early evening. To the south in early evening moving over to the west as the night progresses is the beautiful region of the Milky Way containing both Cygnus and Lyra. Below is Aquilla. The three bright stars Deneb (in Cygnus), Vega (in Lyra) and Altair (in Aquila) make up the "Summer Triangle". East of Cygnus is the great square of Pegasus - adjacent to Andromeda in which lies M31, the Andromeda Nebula. To the north lies "w" shaped Cassiopeia and Perseus. The constellation Taurus, with its two lovely clusters, the Hyades and Pleiades is rising in the east during the late evening.

    • The constellations Lyra and Cygnus. This month the constellations Lyra and Cygnus are seen almost overhead as darkness falls with their bright stars Vega, in Lyra, and Deneb, in Cygnus, making up the "summer triangle" of bright stars with Altair in the constellation Aquila below.

    • Lyra is dominated by its brightest star Vega, the fifth brightest star in the sky. It is a blue-white star having a magnitude of 0.03, and lies 26 light years away. It weighs three times more than the Sun and is about 50 times brighter. It is thus burning up its nuclear fuel at a greater rate than the Sun and so will shine for a correspondingly shorter time. Vega is much younger than the Sun, perhaps only a few hundred million years old, and is surrounded by a cold,dark disc of dust in which an embryonic solar system is being formed!

      There is a lovely double star called Epsilon Lyrae up and to the left of Vega. A pair of binoculars will show them up easily - you might even see them both with your unaided eye. In fact a telescope, provided the atmosphere is calm, shows that each of the two stars that you can see is a double star as well so it is called the double double!

      Between Beta and Gamma Lyra lies a beautiful object called the Ring Nebula. It is the 57th object in the Messier Catalogue and so is also called M57. Such objects are called planetary nebulae as in a telescope they show a disc, rather like a planet. But in fact they are the remnants of stars, similar to our Sun, that have come to the end of their life and have blown off a shell of dust and gas around them. The Ring Nebula looks like a greenish smoke ring in a small telescope, but is not as impressive as it is shown in photographs in which you can also see the faint central "white dwarf" star which is the core of the original star which has collapsed down to about the size of the Earth. Still very hot this shines with a blue-white colour, but is cooling down and will eventually become dark and invisible - a "black dwarf"!

      M56 is an 8th magnitude Globular Cluster visible in binoculars roughly half way between Albireo (the head of the Swan) and Gamma Lyrae. It is 33,000 light years away and has a diameter of about 60 light years. It was first seen by Charles Messier in 1779 and became the 56th entry into his catalogue.

    • Cygnus, the Swan, is sometimes called the "Northern Cross" as it has a distinctive cross shape, but we normally think of it as a flying Swan. Deneb, the arabic word for "tail", is a 1.3 magnitude star which marks the tail of the swan. It is nearly 2000 light years away and appears so bright only because it gives out around 80,000 times as much light as our Sun. In fact if Deneb where as close as the brightest star in the northern sky, Sirius, it would appear as brilliant as the half moon and the sky would never be really dark when it was above the horizon!

      The star Albireo, which marks the head of the Swan, is much fainter, but a beautiful sight in a small telescope. This shows that Albireo is made of two stars, amber and blue-green, which provide a wonderful colour contrast. With magnitudes 3.1 and 5.1 they are regarded as the most beautiful double star that can be seen in the sky.

      Cygnus lies along the line of the Milky Way, the disk of our own Galaxy, and provides a wealth of stars and clusters to observe. Just to the left of the line joining Deneb and Sadr, the star at the centre of the outstretched wings, you may, under very clear dark skies, see a region which is darker than the surroundings. This is called the Cygnus Rift and is caused by the obscuration of light from distant stars by a lane of dust in our local spiral arm. The dust comes from elements such as carbon which have been built up in stars and ejected into space in explosions that give rise to objects such as the planetary nebula M57 described above.

      There is a beautiful region of nebulosity up and to the left of Deneb which is visible with binoculars in a very dark and clear sky. Photographs show an outline that looks like North America - hence its name the North America Nebula. Just to its right is a less bright region that looks like a Pelican, with a long beak and dark eye, so not surprisingly this is called the Pelican Nebula.

    • Pegasus. The Square of Pegasus is in the south during the evening and forms the body of the winged horse. The square is marked by 4 stars of 2nd and 3rd magnitude, with the top left hand one actually forming part of the constellation Andromeda. The sides of the square are almost 15 degrees across, about the width of a clenched fist, but it contains few stars visible to the naked eye. If you can see 5 then you know that the sky is both dark and transparent! Three stars drop down to the right of the bottom right hand corner of the square marked by Alpha Pegasi, Markab. A brighter star Epsilon Pegasi is then a little up to the right, at 2nd magnitude the brightest star in this part of the sky. A little further up and to the right is the Globular Cluster M15. It is just too faint to be seen with the naked eye, but binoculars show it clearly as a fuzzy patch of light just to the right of a 6th magnitude star.

    • Andromeda. The stars of Andromeda arc up and to the left of the top left star of the square, Sirra or Alpha Andromedae. The most dramatic object in this constellation is M31, the Andromeda Nebula. It is a great spiral galaxy, similar to, but somewhat larger than, our galaxy and lies about 2.5 million light years from us. It can be seen with the naked eye as a faint elliptical glow as long as the sky is reasonably clear and dark. Move up and to the left two stars from Sirra, these are Pi and Mu Andromedae. Then move your view through a right angle to the right of Mu by about one field of view of a pair of binoculars and you should be able to see it easily. M31 contains about twice as many stars as our own galaxy, the Milky Way, and together they are the two largest members of our own Local Group of about 3 dozen galaxies.

    • M33 in Triangulum. If, using something like 8 by 40 binoculars, you have seen M31 as described above, it might well be worth searching for M33 in Triangulum. Triangulum is the small faint constellation just below Andromeda. Start on M31, drop down to Mu Andromedae and keep on going in the same direction by the same distance as you have moved from M31 to Mu Andromedae. Under excellent seeing conditions (ie., very dark and clear skies) you should be able to see what looks like a little piece of tissue paper stuck on the sky or a faint cloud. It appears to have uniform brightness and shows no structure. The shape is irregular in outline - by no means oval in shape and covers an area about twice the size of the Moon. It is said that it is just visible to the unaided eye, so it's the most distant object in the Universe that the eye can see. The distance is now thought to be 3.0 Million light years - just greater than that of M31.

    • The constellation Taurus. Taurus is one of the most beautiful constellations and you can almost imagine the Bull charging down to the left towards Orion. His face is delineated by the "V" shaped cluster of stars called the Hyades, his eye is the red giant star Aldebaran and the tips of his horns are shown by the stars beta and zeta Tauri. Although alpha Tauri, Aldebaran, appears to lie amongst the stars of the Hyades cluster it is, in fact, less than half their distance lying 68 light years away from us. It is around 40 times the diameter of our Sun and 100 times as bright.

    • The Hyades and Pleiades. To the upper right of Taurus lies the open cluster, M45, the Pleiades. Often called the Seven Sisters, it is one of the brightest and closest open clusters. The Pleiades cluster lies at a distance of 400 light years and contains over 3000 stars. The cluster, which is about 13 light years across, is moving towards the star Betelgeuse in Orion. Surrounding the brightest stars are seen blue reflection nebulae caused by reflected light from many small carbon grains. These reflection nebulae look blue as the dust grains scatter blue light more efficiently than red. The grains form part of a molecular cloud through which the cluster is currently passing. (Or, to be more precise, did 400 years ago!)

    • The Crab Nebula. Close to the tip of the left hand horn lies the Crab Nebula, also called M1 as it is the first entry of Charles Messier's catalogue of nebulous objects. Lying 6500 light years from the Sun, it is the remains of a giant star that was seen to explode as a supernova in the year 1056. It may just be glimpsed with binoculars on a very clear dark night and a telescope will show it as a misty blur of light.

      Its name "The Crab Nebula" was given to it by the Third Earl of Rosse who observed it with the 72 inch reflector at Birr Castle in County Offaly in central Ireland. As shown in the drawing above, it appeared to him rather like a spider crab. The 72 inch was the world's largest telescope for many years. At the heart of the Crab Nebula is a neutron star, the result of the collapse of the original star's core. Although only around 20 km in diameter it weighs more than our Sun and is spinning 30 times a second. Its rotating magnetic field generates beams of light and radio waves which sweep across the sky. As a result, a radio telescope will pick up very regular pulses of radiation and the object is thus also known as a Pulsar. Its pulses are monitored each day at Jodrell Bank with a 13m radio telescope.

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during November 2020.

    The evening sky of November holds the Maori asterism of Te Waka O Tamarereti, which depicts one of my favourite cultural interpretations of how the stars ended up in the night sky. Here in New Zealand, this time of the year, after sunset, we see the Milky Way surrounding the horizon; when it's like that, the galaxy here looks like a river. Move away from the light polluted cities and you should be able to clearly see it wrapping around the horizon, this is how dark the sky is in New Zealand, throughout the entire country.

    Planets

    • In November 2020, Jupiter and Mars are the brightest objects we can see first after sunset. Jupiter is in the western sky and Mars is in the north. As the sky darkens, Saturn appears just above Jupiter. Jupiter and Saturn are now visually very close, enough to be in the same binocular view. Every 20 years Jupiter catches up on Saturn but of course this is an illusion as they are on the same line of sight but at different distances from Earth. Unseen to the naked eye, very close to Jupiter is Pluto.
    • In the morning sky, Venus rises a little south of east an hour before the Sun all month. Mercury might be seen in the dawn mid-month, below and right of Venus, and much fainter, rising 35 minutes before the Sun.

    Constellations

    • By mid month, Te waka o Tamarereti is clearly visible in the sky. Starting from the West, Antares the red giant heart of Scorpius is setting and the asterism of the fish hook of Maui is now the prow of the waka. To the South, the two stars pointing to the Southern Cross, Alpha Centauri and Beta Centauri are now the rope of the waka, the Southern Cross is the anchor. Interesting to see, due to precession, about 2000 years ago the Southern Cross as seen from New Zealand, would have completely disappeared beyond the horizon just like an anchor. That was the time when Canopus, the second brightest star in the sky, was visible from Greece. Canopus is a circumpolar star, which means it is always in the sky, for Maori he is Atutahi, the chief of all stars. Two other stars that were visible from Europe 2000 years ago are Alpha and Beta Centauri. They are part of the constellation of Centaurus.
    • Next in line is the Southern Cross, pointing down at this time of the year, indicating South just like an arrow. Southern Cross is also circumpolar from New Zealand. The Southern Cross points at Achernar, also a circumpolar star here, which is now very high in the sky. Each side of this imaginary line that goes from the Southern Cross to Achernar, at about two thirds from the Southern Cross and one third from Achernar, are the two Magellanic clouds.
    • Close to the horizon, in the asterism of te Waka O Tamarereti, is Sirius, the brightest star in the sky, which rises a little south of due east after sunset. By the end of the month it will be up at sunset. This time of the year, from New Zealand we can see the brightest star in the sky, Sirius, second brightest star, Canopus and third brightest star in the sky Alpha Centauri, in the same time.
    • Left of Sirius is the constellation of Orion, which is the taurapa, or the end of the waka. In New Zealand, Orion's belt makes the beautiful and practical asterism of 'The Pot'. Also in Orion, Rigel, a blue supergiant star, is directly above the line of three stars; Betelgeuse, a red-giant star, is straight below. To the left, orange Aldebaran and the Hyades cluster along with the Pleiades which are further left make the feathers of the canoe and the ripples in the water.

    Deep Sky Objects

    • The Large Magellanic Cloud is on the eastern side of the imaginary line and the Small Magellanic Cloud on the western side of it. The Small Magellanic Cloud is 200,000 light years away from us. A fuzzy patch very close to the Small Magellanic Cloud is the beautiful 47 Tucanae globular cluster. The cluster is however, much closer to us, at only 16,000 light years away. The Large Magellanic Cloud is a symphony of stars, at about 160,000 lights years away. A dwarf irregular galaxy, the Large Magellanic Cloud is visually located on the border between the constellations Dorado and Mensa, and is one of very few galaxies that are visible to the naked eye. It really looks like a cloud. The Tarantula nebula in the large Magellanic Cloud is a beautiful object in a good telescope.
    • Very low in the north we observed through our own 16' telescope the Andromeda Galaxy, but you do need a clear sky north and a low horizon to be able to see it. It was truly a spindle of light. Andromeda is the furthest object we can see with the naked eye and we just can make it up from here.
    • Close to Zenith is Achernar from Eridanus, all the beautiful stars of Grus and Fomalhaut. In Grus, the Grus Quartet is now visible. In Sculptor, the famous Sculptor galaxy is in a good position to observe. This galaxy has a visual magnitude of about 7 and it is visible with the naked eye, it looks like a blurred star. Sculptor galaxy is about 12 million light years away from us.
    2 December 2020, 6:00 pm
  • 20 minutes 31 seconds
    The night sky for October 2020

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during October 2020.

    The Planets

    • Jupiter Jupiter is now visible, low in the sky, just west of south when darkness falls as October begins and sets around 10:30 pm BST. Towards the end of the month it will be seen towards the southwest after sunset and sets by ~08:30 pm GMT. Its magnitude dims slightly from -2.4 to -2.2 during the month whilst its angular diameter falls from 40.5 to 37.1 arc seconds. Sadly, even when first seen after sunset, it will only have an elevation of ~14 degrees above the horizon so the atmosphere will limit our views. Due its position in the most southerly part of the ecliptic this has been a very poor opposition for those of us in the northern hemisphere..

    • Saturn Saturn, following Jupiter into the sky, some 8 degrees behind at the start of the month but reducing to 5.2 degrees by Halloween, Saturn is best seen in the south just after sunset on the 1st. Its magnitude drops slightly during the month from +0.5 to +0.6 whilst its angular size decreases from 17.2 to 16.4 arc seconds. The rings span some 35 arc seconds across and, at ~22 degrees to the line of sight, show up well. Saturn lies in Sagittarius near the border of Capricornus. Saturn halted its retrograde motion on the 29th of September and, as the year progresses becomes closer to Jupiter until, on the 21st December they are just 0.1 degrees apart. Sadly again, its low elevation of ~16 degrees when crossing the meridian will somewhat limit our views of this most beautiful planet..

    • Mercury Mercury passes in front of the Sun on the 25th of the month (inferior conjunction) and will not be visible this month..

    • Mars See highlight above..

    • Venus Venus, was at greatest elongation east back on August 12th but still dominates the pre-dawn sky rising around three hours before sunrise as October begins and a little less by month's end. It shines at magnitude -4.1 as October begins, lying some half a degree from Regulus in Leo, dropping to -4 by month's end whilst its angular size shrinks from 15.5 to 13.2 arc seconds. During the same time its its phase (the illuminated percentage of the disk) increases from 72% to 81% which is why the fall in magnitude is so small. It still reaches an elevation of ~32 degrees at sunrise. Venus entered the constellation of Leo on the 23rd of September and moves into Virgo on the 23rd of the month..

    Highlights of the Month

    October - a great month to view Mars. During this opposition, Mar's southern hemisphere is tipped towards the Earth and so the South Polar Cap should be visible, though much of its frozen carbon dioxide will have vaporised during the Martian summer. Though the North Polar Cap is beyond our view, one should be able to spot the haze of the North Polar Hood lying above the northern limb of the planet. At 24.6 hours long, the Martian day is similar to ours, so the surface details remain similar at the same time each night. Mars takes 41 days to make an apparent rotation as seen from Earth..

    October - Find NeptuneThis month Neptune is just pass opposition and so will be visible during much of the night. It lies in Aquarius below one of the circlets in Pisces and shines at magnitude +7.8 having a 2.4 arc second disc so binoculars or a telescope will be needed to spot it under a dark sky. I hope the charts will help you find it - not so difficult as it lies close to a nice grouping of stars. Of course, a well aligned computerised telescope will take you right there but, unless the seeing is exceptional, I suspect that the dark bluish disk will not be that obvious..

    October, evening: the Double Cluster and the 'Demon Star', Algol. This month is a good time to look high in the east towards the constellations of Cassiopea and Perseus. Perseus contains two interesting objects; the Double Cluster between the two constellations and Algol the 'Demon Star'. Algol in an eclipsing binary system as seen in the diagram below. Normally the pair has a steady magnitude of 2.2 but every 2.86 days this briefly drops to magnitude 3.4..

    October: find M31 - The Andromeda Galaxy - and perhaps M33 in Triangulum Around new Moon (16th October) - and away from towns and cities - you may also be able to spot M33, the third largest galaxy after M31 and our own galaxy in our Local Group of galaxies. It is a face on spiral and its surface brightness is pretty low so a dark, transparent sky will be needed to spot it using binoculars (8x40 or, preferably, 10x50). Follow the two stars back from M31 and continue in the same direction sweeping slowly as you go. It looks like a piece of tissue paper stuck on the sky just a bit brighter than the sky background. Good Hunting!.

    October 2nd - 1 hour before sunrise - Venus and Regulus Before dawn on the 2nd of the month, if clear, one will spot Venus sining at magnitude -4.1 just half a degree to the upper right of Regulus, Alpha Leonis..

    October 10th - before dawn: The third quarter Moon close to Pollux in Gemini. Before dawn on the 10th of October, the third quarter Moon will lie down to the right of Pollux in Gemini..

    October 14th - before dawn : Venus and a very thin crescent Moon. Before dawn on the 14th should it be clear, Venus will be seen below a very thin waning crescent Moon. One may well be able to spot 'Earthshine' the dark side of the Moon lit by light reflected form the Earth..

    October 22nd - after sunset : Jupiter, Saturn and a waxing Moon After sunset on the 22nd, Jupiter will be seen above a waxing Moon, one day before first quarter with Saturn up to its left..

    October 29th - evening : Mars and a near full Moon.During the evening of the 29th, Mars will lies above the waxing Moon just 2 days before full..

    October 7th and 23rd evening: the Hyginus Rille For some time a debate raged as to whether the craters on the Moon were caused by impacts or volcanic activity. We now know that virtually all were caused by impact, but it is thought that the Hyginus crater that lies at the centre of the Hyginus Rille may well be volcanic in origin. It is an 11 km wide rimless pit - in contrast to impact craters which have raised rims - and its close association with the rille of the same name associates it with internal lunar events. It can quite easily be seen to be surrounded by dark material. It is thought that an explosive release of dust and gas created a vacant space below so that the overlying surface collapsed into it so forming the crater. On the evenings given above, the rille lies near the terminator..

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during October 2020.

    SEE WITH THE NAKED EYE 

    Visible planets this month in order of disappearance:  Mercury, Jupiter, Saturn, and Mars. If you are lucky to have a flat horizon in the northeast and like planet Venus, you will be seeing it in the morning sky. This month, Mercury will reach its highest point in the evening sky on the 2nd of October and Mars will be at opposition, closest to Earth, on the 14th of October. Thus we will be able to easily see features from Mars in a telescope. 

    The Sun is in the zodiacal constellation of Virgo. It sets around 07:23PM and rises around 07:00AM.

    Mercury is in Virgo, about 9 light minutes away.

    Venus is in Leo, visually very close to the Sun. Is about 8 light minutes away. 

    Mars is visually in the zodiacal constellation Pisces, at a distance of just about 4 light minutes away. 

    Jupiter is in the constellation of Sagittarius of about 40 light minutes from Earth.

    Saturn is visually in Sagittarius, 80 light minutes away. 

    SEE WITH BINOCULARS AND TELESCOPE

    Uranus is in Aries. It has a visual magnitude of +5.7 so under a very dark sky and if you have amazingly good eyes you might be able to see it, with the naked eye. It’s about 158 light minutes away approx. 

    Neptune is in the evening sky, in Aquarius. It takes light approximately 4 hours to reach us from Neptune. At a visual magnitude of +7.8 you will need binoculars or telescopes to see it. 

    Pluto in Sagittarius, very close to Jupiter. We cannot see Pluto with the naked eye, as it has a magnitude of +14.4 is 5059 million kilometres away, at about 281 light minutes – more than 4 hours and 30 light minutes. 

    IN OCTOBER

    The Milky Way’s centre is now on the western horizon after sunset. Scorpius and Sagittarius are the two constellations whose stars are between us and the galactic centre. We are very lucky here in New Zealand to see the centre of the Milky Way high in the sky, which means we are looking at it through less layers of atmosphere than in the Northern Hemisphere. In the Northern Hemisphere, from mid latitudes, the centre of the Milky Way climbs only about 30 degrees above the horizon. 

    October is a good month to still see many deep sky objects. The majority of them are around the galactic bulge. In Scorpius, our favourites are: Ptolemy’s cluster – M7 a beautiful open cluster of stars, the Butterfly Cluster – M6, which resembles a butterfly, and the globular clusters Messier 4 and Messier 80. The Bug Nebula NGC 6302 and The Cat’s Paw nebula – NGC 6334 are excellent astrophotography targets. Neighbouring Scorpius is Sagittarius. This is the constellation where we map the centre of our galaxy, the Milky Way. Sagittarius’s famous asterism (grouping of stars) is the teapot, which is visible upside down here in New Zealand. Sagittarius cannot be seen from Scotland or Scandinavia. We are very lucky here to be able to observe it overhead.

    The Milky Way is at its densest in Sagittarius.  Inside the constellation, which is a patch of the sky, we can admire two beautiful Star Clouds, easily seen in binoculars: the Large Sagittarius Star Cloud and the Small Sagittarius Star Cloud – Messier 24. Some stunning deep sky objects in Sagittarius are Lagoon Nebula – M8, Omega Nebula or Swan Nebula and the Trifid Nebula, another famous one also known as M20. The Trifid Nebula is about 2 degrees from Lagoon Nebula.

    In the circumpolar region, the Small Magellanic Cloud is in a good position to observe. Close to it, 47 Tucanae is one of the most beautiful and large globular clusters that adorn the night sky. 47 Tucanae is the second brightest globular cluster in the sky and one of the most massive clusters in the Galaxy. It’s angular diameter is roughly the size of the full Moon, that is the width of your pinky at arm’s length. It can be seen with the naked eye from Earth although it is far far away, about 13,000 light years from Earth.

     The three famous crosses of the southern sky, the Southern Cross, Diamond Cross and the false cross are very low on the horizon, and for the next three months we will be looking at them through an extra layer of atmosphere. 

    Some notable deep sky objects this month are Helix Nebula in Aquarius, Dumbbell Nebula in Vulpecula and the Grus Quartet in Grus. Famous for its nickname “The Eye of Sauron” Helix Nebula is a very large planetary nebula. Dumbbell Nebula – M27 in Vulpecula is very bright and the first planetary nebula to be discovered. In Grus, a gathering of four interacting galaxies are known as the Grus Quartet. They are fascinating to see in a large telescope. 

    Bright Objects

    Beautiful bright stars are visible in the night sky. Right at the top of the sky, Antares, the red giant and main star from Scorpius shimmers in an incredibly beautiful red colour as seen through a telescope. On the southern horizon lays Canopus, glistening all colours, including red and green as we see it through the atmosphere. On the opposite side, on the northern horizon is Altair, the main star in Aquila.

    Just after sunset, at the beginning of the month, you can catch a good view of planet Mercury, which now reaches its highest point in the sky and sets about two hours after the Sun. Jupiter and Saturn are evening objects, they are visible at Zenith. Mars is visible after 9 PM and Venus is just slightly visible in the morning, rising one hour before the Sun.

    28 October 2020, 2:00 pm
  • 28 minutes 23 seconds
    The night sky for September 2020

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during September 2020.

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during September 2020.

    The First point of Libra

    These fancy words are naming the point on the celestial map where from Earth it looks like the Sun shifts celestial hemispheres. As the Sun is changing its position in relation to the background stars every day, the two main lines you will find on a celestial map, the celestial equator (see above) and the ecliptic cross over at equinoxes. 2000 years ago the September crossover occurred in the constellation Libra. Due to Earth’s wobble, which has a spinning top movement, the crossover happens now in Virgo. Astronomers however kept the First point in Libra as the name for the September equinox. In 400 years from now it will be in Leo. (by the way this is the same reason why the time when the Sun is in any particular zodiacal constellation shifted back with almost a month too. The equinox is only a moment in time as Earth continuously moves as it orbits around the Sun.

    What’s the Sun up to?

    According to TimeandDate.com, September Equinox in Wellington, New Zealand is on Wednesday, 23 September 2020 at 1:30 a.m. NZST. As the month goes, the days will be longer than the nights until we reach Summer Solstice. Since the equinoxes only occur twice per year they are very special astronomical events.

    Since 1870s New Zealand used the meteorological dates to mark the beginning of spring, thus spring here begins on the 1st of September! People who come here from the Northern Hemisphere usually think that spring begins at the autumnal equinox- which by the way is on the 23rd. But just for the sake of the argument, according to WeatherWatch Managing Director Philip Duncan, there are actually four ways to start a season (1) looking at astronomical dates, which would place the date on September 22 or 23, based on the equinox, (2) by meteorological dates – which is a three-month division of the year into seasons, thus Spring starts on September 1, (3) observing the solar winter, which is the three “darkest” months with the June 21-22 winter solstice in the middle, which shifts the beginning of spring to August 8 and (4) looking at what nature does, which in New Zealand is hard to pin down.

    The Milky Way and Zodiacal Light

    In September, the asterism of Scorpius is at this time of the year the Fishhook of Maui that drags the Milky Way down from the sky. We get to admire the amazing galactic centre and the Milky-Way.kiwi inside it which is fantastic. Enjoy it while it lasts!

    In addition to the Milky Way, if you are stargazing from somewhere with very dark skies, you can spot what is called the “Zodiacal Light”. It's a cone-shaped light that stretches from low on the horizon along the ecliptic. Yes, it is the ecliptic again!! The zodiacal light is the light we see reflected from dust and ice particles in the plane of our own solar system! How cool is that? So in the sky we can see both the galaxy that we inhabit and the solar system. Two objects at two completely different scales! And in different parts of the sky as well. But the part of the sky where we observe the Zodiacal Light, is where the ecliptic would be. Once you;ve learned where that is you will see it is very useful, especially at figuring out where the planets are in the sky, as they orbit around the Sun in the same path, you’ve guessed it on the ecliptic. But because some of their orbit planes are ever so slightly on an angle compared to Earth’s plane, they don't match perfectly so that’s why the Zodiacal band is a band of stars about 8 degrees each side of the ecliptic as that’s where the planets are visible.

    Scorpius, Centaurus and Southern Cross

    After sunset, you can see the fish hook at Zenith and then falling down towards the western part of the sky. Scorpius Te Matau a Maui has a magnificent red supergiant star Antares, Maori call it Rehua. It is the Summer wife of the Sun. In a telescope it looks like a beautiful ruby and is impossible to miss on a clear night. It looks quite reddish, just like planet Mars! The name Antares is the rival of Mars, as planet Mars sometimes gets very close to Antares, because Antares is one of those stars on the Zodiacal Band. When this happens the two of them rival in redness and brightness. I believe Mars wins but that’s just because is made of iron. We took a lot of images of Antares recently with our new fantastic project the Slooh Telescopes and it’s a really big star.

    Scorpius has some fabulous deep sky objects. Also with Slooh, we took a heap of them over the last month.Cat Paw’s nebula this one is a good astrophotography target, The Butterfly Cluster, or M6 which you can also see in a telescope, it’s an open cluster of stars, M7 also known as Ptolemy’s cluster is also an open cluster M4, the globular cluster near Antares. NGC 6231 or Melotte 153 is a beautiful open cluster as well which was discovered as far back as 1654 by Giovanni Hodierna, who listed it as “luminosae” in his catalogue. South of Scorpius you can find the constellation of Centaurus, a creature that is half-human and half-horse in Greek mythology, home of Alpha, Beta and Omega Centauri.This time of the year it is very high in the sky so in a good position to observe.

    Circumpolar objects to New Zealand

    In September, in the evenings, you will find the Southern Cross in the south western part of the sky. So just after sunset is at the 3 o’clock position heading down followed by the pointers. Canopus would be at the same time grazing the southern horizon so hard to see from hilly Wellington. Achernar and the two Magellanic Clouds would be in the south eastern part of the sky.Some other bright stars Just after sunset, Virgo will be on the western horizon, very close to the Sun. It will be visible only in the first part of the month, with the beautiful star Spica sinking beyond the horizon by the middle of the month. In Libra, Zubenelgenubi and Zubeneschamali are the former claws of scorpius, now the scales of justice. Some sources say that they have been chopped from Scorpius and recreated into a scale of justice at the time when the First Point of Libra was in Libra, which is why Libra was created by our ancestors, not because they noticed that people born that time of the year were indecisive, or always tried to get revenge or where weighing their arguments carefully, but to mark one of the two equinoxes. Sagittarius has many beautiful bright stars, and I love the particular teapot shape it has which now can be seen as the constellation is at Zenith. Nunki is our favourite star this month also because we took a picture of it recently.

    In the north, we can see the bright star Altair in Aquila, the constellation of the eagle, a triangle-shaped constellation in north-eastern skies. Lower on the northern horizon, mirroring somewhat Canopus, the second brightest star in the sky which is lower on the southern horizon, is Vega, nicknamed Antopus by the awesome Ian Cooper. This is a play of words with Antares, which means the rival of Mars, Ian says that Vega rises low in the north when Canopus is low in the south and they are like two rivals eyeing each other up. Another beautiful star is Albireo, in Cygnus. It is a spectacular blue and red giant double. Only about 10 degrees above the horizon, the stars of Lyra, where Vega lays, also host a fabulous Messier object, which is really easy to see in a telescope, that is M57 the Ring Nebula, the remnants of a star. In astronomical terms it is a planetary nebula. Nearby, another one of its kind, remnants of another star that died is in Vulpecula, M 27 – Dumbbell Nebula is another good target. As they are not so good to photograph from Wellington, we've just been using the telescopes from Slooh which have prime views of these amazing objects. Probably the best star and one of my favourite objects in the night sky is Albireo, which we also view with Slooh, just because it is too low to photograph.

    21 September 2020, 11:30 am
  • 16 minutes 35 seconds
    The night sky for August 2020

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during August 2020.

    The Planets

    • Jupiter. Visible throughout the hours of darkness and lying up to the left of the 'teapot' in Sagittarius, Jupiter reached opposition on July 14. It is now visible in the south-southeast as darkness falls and crosses the meridian, so highest in elevation, at 11:30pm BST at the start of the month and by 9:30pm by month's end. Its magnitude dims slightly from -2.7 to -2.6 during the month whilst its angular diameter falls from 47 to 44 arc seconds. Sadly, even when due south, it will only have an elevation of ~16 degrees above the horizon so the atmosphere will limit our views. A 'highlight' gives the times when the Great Red Spot faces the Earth.

    • Saturn. Following Jupiter into the sky, some 8 degrees behind Jupiter as August begins, Saturn reached opposition on the 20th of July so, again, is visible throughout the hours of darkness - along with Jupiter dominating the southern sky in the late evening. Its magnitude drops slightly during the month from +0.1 to + 0.3 whilst its angular size decreases from 18.4 to 18 arc seconds. The rings span some 42 arc seconds across and, at 22 degrees to the line of sight, have opened out very slightly from previous months. Saturn lies in Sagittarius close to the boarder of Capricornus. Sadly again, its low elevation of ~16 degrees when crossing the meridian will somewhat limit our views of this most beautiful planet.

    • Mercury is barely visible in the pre-dawn sky as August begins with a magnitude of -0.9 and a 6.1 arc second disk but, moving away from the Earth, passes behind the Sun on August 17th.

    • Mars, in Pisces, can be seen towards the southeast at the start of the month rising 3 hours after sunset as August begins and 2 hours by its end. Its magnitude will rise from -1.1 to -1.8 during the month as its angular size increases from 14.6 to 18.7 arc seconds. It reaches an elevation of ~40 degrees as dawn approaches so amateur telescopes will enable one to see features, such as Syrtis Major, on its surface when the seeing conditions are good.

    • Venus rises about 2am in the north north-east throughout the month but, as the Sun rises later as the days pass, the interval between Venus-rise and Sunrise increases by about 20 minutes. It shines at magnitude -4.5 as August begins, dropping to -4.3 by month's end whilst its angular size shrinks from 27 to 20 arc seconds. During the same time its phase (the illuminated percentage of the disk) increases from 43% to 59% which is why the fall in magnitude is not that great. Venus reaches greatest elongation west on August 12th, some 46 degrees away from the Sun. In Taurus as August begins, it passes into the upper left of Orion on the 5th before moving into Gemini on the 13th ending the month some 9 degrees below Pollux, the head of one of the 'twins'.

    Highlights

    • August - a great month to view Jupiter. This is a great month to observe Jupiter which will be visible during all the hours of darkness. It lies in the southernmost part of the ecliptic in Sagittarius and, sadly, will only reach an elevations of ~16 degrees when crossing the meridian. An interesting observation is that the Great Red Spot appears to be diminishing in size. At the beginning of the last century it spanned 40,000 km across but now appears to be only ~16,500 km across - less than half the size. It used to be said that 3 Earths could fit within it, but now it is only one. The shrinking rate appears to be accelerating and observations indicate that it is now reducing in size by ~580 miles per year. Will it eventually disappear?
      The features seen in the Jovian atmosphere have been changing quite significantly over the last few years - for a while the South Equatorial Belt vanished completely but has now returned to its normal wide state.

    • August: Look for the Great Red Spot on Jupiter. A list on the 'Night Sky' page gives the best late evening times during August to observe the Great Red Spot which should then lie on the central meridian of the planet and so face the Earth. The times are in UT.

    • August 1st - late evening: Jupiter, Saturn and a waxing gibbous Moon. In the late evening should it be clear, Jupiter will be seen towards the south above a waxing gibbous Moon with Saturn over to its left.

    • August 9th - late evening: Mars above a waning Moon. Looking towards the south-east in the late evening, Mars will be seen up to the left of the Moon, 1 day before 3rd quarter.

    • The mornings of August 12th and 13th - midnight to dawn: look out for the Perseid meteor shower. If clear, these mornings should give us a chance of observing the Perseid meteor shower - produced by debris from the comet Swift-Tuttle. The early morning of the 12th August will give us the best chance, if clear, of viewing the shower, but the peak is quite broad and so it is well worth observing on the nights before and after. Most meteors are seen looking about 50 degrees from the "radiant" which lies between Perseus and Cassipeia. On the 11th, the Moon, at third quarter, rises just after midnight so its light will begin to hide the fainter meteors. On the 12th and 13th it rises later and its phase will have reduced so its effects will be less. NB: As we need to view a very wide area of sky, normal binoculars would be of no use but the Vixen SG 2.1 x 42 that I have reviewed in the Astronomy Digest could be useful albeit over the smaller field of view of ~27 degrees.

    • August 15th - before dawn : Venus below a very thin crescent Moon. Just before dawn on the 15th, and given a low horizon between the east and northeast, it might be possible to spot Venus below a very thin crescent Moon. Binoculars may well be needed, but please do not use them after the Sun has risen.

    • August 31st - six minutes past 5am BST: Mars and the International Space Station. If it is clear before dawn on the 31st of the month, you could see (assuming Stellarium is right) the International Space Station pass very close to Mars at around 05:06:45 BST. Just under 30 seconds later it will pass the Pleiades Cluster.

    • August 9th and 25th - evening: The Hyginus Rille. These evenings, should it be clear, are a superb time to view the Hyginus Rill as it will lie close to the terminator. For some time a debate raged as to whether the craters on the Moon were caused by impacts or volcanic activity. We now know that virtually all were caused by impact, but it is thought that the Hyginus crater that lies at the centre of the Hyginus Rille may well be volcanic in origin. It is an 11 km wide rimless pit - in contrast to impact craters which have raised rims - and its close association with the rille of the same name associates it with internal lunar events. It can quite easily be seen to be surrounded by dark material. It is thought that an explosive release of dust and gas created a vacant space below so that the overlying surface collapsed into it so forming the crater.

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during August 2020.

    In August 2020 we have a couple of spectacular planets in the evening sky, Jupiter and Saturn, the centre of our galaxy climbs at zenith and with it all the beautiful deep sky objects that we are so looking forward to seeing every year. Unfortunately for us, although there are many meteor showers in the northern part of the sky, they are quite low on the horizon for us to enjoy them as northern hemispherians do. Here is what’s in the sky in August.

    Planets

    • Mars. With the launch of NASA’s Perseverance as well as the UAE’s and China’s Mars missions, all eyes are on Mars for the next few months. Our eyes will be on Mars as well because from now until October Mars is only going to get better and better in the night sky. At the start of the month it rises at just after 11pm in Pisces and is about 95 million kilometres away. At that distance it is 14.6 arcseconds in size, which is not much smaller than Saturn, less the rings.
      By the end of the month the red planet is still in Pisces and rising at just before 10pm and has got about 20 million kilometres closer to us. This will put Mars at a size of nearly 19 arcseconds in the eyepiece, bigger than Saturn and just under half the size of Jupiter. By early October it will be just over 60 million kilometres away and nearly 23 arcseconds in size. You’ve got two months to get used to observing the red planet and improving your imaging skills to capture the stunning details of the planet as it reaches opposition.
      When it is so close to Earth, you can even draw Mars as you look at it through a telescope. And the best thing about that is that the main feature that we see through the telescope, the top / or bottom of Syrtis Major is where Perseverance is headed to.

    • Saturn. The two gas giants that are dominating the evening sky are also a great sight to see over August. Saturn rises between Capricornus and Sagittarius before sunset at around 4:20pm and by sunset is nearly 15 degrees above the horizon. At the end of the month it is rising two hours earlier so it is in a very favourable position for observing in the early evening. Opposition for Saturn is on 2 Aug 2021 so we’ve got a year to wait, though at 1.4 billion kilometres it is not going to look a lot different throughout the months.

    • Jupiter rises about 40 minutes before Saturn in Sagittarius throughout the month and joins Saturn in a very favourable viewing position in the early evening, great for the astronomer who likes to get to bed early. A great feature of Jupiter is that you can witness an eclipse many times a month. One of these is from 9:18pm on 7th of August when you watch Europa disappear into the brightness of Jupiter followed by the shadow appearing on the planet’s disk at 10:25pm.

    • Venus tracks its way closer and closer to the Sun in our early morning sky throughout the month. The brightest of the planets is visible just below Orion and ends the month near Procyon in Canis Minor. Mercury is heading behind the Sun as the month progresses so is not going to be visible except at the very start of the month, and then with some difficulty.

    Constellations

    • Scorpius has been dominating the night sky so far in Winter as it occupies the zenith in the evening. Now we are seeing Sagittarius rising higher and higher each night and dragging with it the constellation of Capricornus.

    • We have some good news for the people who like golf. From New Zealand, the Capricorn, which is supposed to be a goat (capri) with one horn (corn), alluding to the legend of the horn of plenty, looks in fact exactly like a golf flag, yet a gigantic one.

    • On the other side of Scorpius, Libra the scale is on a descending path onto the horizon and Virgo’s star, Spica is even closer to the horizon.

    • In the morning, we are seeing the return to our skies of Orion, rising earlier and earlier each night. The season of Matariki is closed now and the Pleiades is also becoming more and more visible in the morning sky, rising at 3am.

    Deep Sky

    • Deep Sky objects are fantastic at this time of the year as the centre of the Milky Way reaches the zenith it brings up the amazing nebulae of Omega, Eagle, Triffid and Lagoon. Lagoon is an amazing nebula to view in a telescope with the large open cluster NGC 6530 next to the bright nebula. A short distance away in the Trifid Nebula or M20. It is easy to spot the distinctive shape that led to its common name.

    • Heading down the Milky Way Way towards Scutum you’ll find the Omega Nebula, or M17, this is a bright nebula, easily visible in even modest telescopes. Not far from Omega you’ll find the much fainter Eagle Nebula, M16, which is home to the pillars of creation from the famous Hubble Space Telescope image of this nebula.

    7 August 2020, 4:30 pm
  • 16 minutes 10 seconds
    The night sky for Month 4 2020

    Northern Hemisphere

    Ian Morison tells us what we can see in the night sky above the world's middle line during Month 4 2020.

    The Planets

    • As April begins, Jupiter rises some three and a half hours before the Sun shining at magnitude -2.1. It then follows Mars and precedes Saturn, just above Mars, into the pre-dawn sky. During the month it brightens to magnitude -2.3 whilst its angular size increases from 37.0 to 40.6 arc seconds. A low south-eastern horizon will be needed and our views of the giant planet and its Galilean moons will be somewhat hindered by the depth of atmosphere through which it will be observed.

    • As April begins, Saturn rises at 05:33 UT, 20 minutes after Jupiter, and by its end at 02:50 UT whilst its magnitude increases slightly from +0.7 to +0.6 whilst its angular size increases from 16.1 to 16.9 arc seconds. Saturn reaches ‘quadrature', 90 degrees in angle from the Sun, on April 21st enhancing the three-dimensionality of its globe and rings. At 21 degrees, the rings are slightly less tilted to the line of sight than they have been for some time. Sadly, its low elevation before sunrise will somewhat limit our views of this most beautiful planet.

    • Mercury is lost in the Sun's glare this month, so cannot be observed.

    • Mars can be seen towards the southeast in the pre-dawn sky at the start of the month. It then rises at ~04:48am and will be best seen at around 6am having an elevation of ~8 degrees. It will then have a magnitude of +0.78 and a 6.4 arc second, salmon-pink, disk and lies just inside Capricornus. By month's end it will have moved over to the east of Capricornus and its magnitude will have increased to +0.43 and it angular size to 7.6 arc seconds. Having started the month just below Saturn, it rapidly leaves Saturn and Jupiter as it crosses Capricornus.

    • Venus is still dominating the south-western twilight sky. It reached greatest elongation east from the Sun on the 24th March but is still near its highest possible altitude and April is still one of the very best months to observe it in its 8 year cycle of apparitions. As April begins, it will then have an elevation of ~39 degrees at sunset - about the highest elevation it can ever achieve! During the month its angular size increases from 25.5 to 38.2 arc seconds but, at the same time, it phase (the percentage of the disk illuminated) decreases from 47% to 26% and so the brightness only increases slightly from -4.5 to -4.7 magnitudes. This is about the brightest that Venus ever gets!

    Highlights of the Month

    • April 1st - before dawn: Jupiter, Saturn and Mars. Before dawn on the first of the month, Mars will be seen to lie just below Saturn with Jupiter over to their right.

    • April 3rd - evening: Venus within the Pleiades Cluster. After sunset on the 3rd of April, if clear, Venus will be seen to lie just to the left of Merope within the Pleiades Cluster. A great photographic opportunity!

    • April 15th - before dawn: the Moon joins three planets. Before dawn on the 15th of April, the Moon, just after third quarter, lies below a lineup of Mars, Saturn and Jupiter.

    • April 25th - after sunset: A very thin crescent Moon lies between the Hyades and Pleiades Clusters. If clear after sunset on the 25th of the month, a very thin crescent moon will be seen to lie between the Hyades and Pleiades Clusters in Taurus. It may be possible to spot the 'Old Moon in the New Moon's arms' due to earthshine. Binoculars may well be needed, but please do not use them until after the Sun has set.

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the night sky below the world's middle lineduring Month 4 2020.

    In these very strange times, as we find ourselves locked inside our homes, we might have some ideas as to what to do with the April night sky. Hopefully you’ll be able to actually get out of your house and take your telescope somewhere else to have a look at the night sky.April is a month of action in astronomy and stargazing! Global Astronomy Month (GAM) is organised each April by Astronomers Without Borders and the International Dark Sky Week is also in April, this year from Sunday, April 19 until Sunday, April 26!

    Planets
    • Look for Venus in the evening sky, where it is shining very bright. You can try to see it during daytime if your eyesight is good and you know exactly where to look.
    • Look for Jupiter after midnight at the beginning of the month, and after 10:30 PM towards the end of it - thanks to daylight saving as well as Earth’s revolution around the Sun that among other things makes stars rise 4 minutes earlier every day. Try to spot Saturn and Mars about half an hour after Jupiter.
    • Morning Owls can still enjoy Mercury as well as a beautiful arch of planets stretching across the sky and are welcome to tell us if it is worth waking up that early to see them. Sadly Mercury will disappear in the twilight of the rising Sun at the end of the month.

    Stars

    • Try to see the brightest stars in the sky - now is the time (as it was last month but we can still enjoy these in April). They are Sirius, the dog star, Canopus the cat star and Alpha Centauri, our closest neighbour 41.3 trillion kilometres away (so in the safe zone). Although, technically Sirius and Alpha Centauri are double stars, so then are they the three brightest stars or the five brightest stars?

    Galaxies

    • Milky Way - the obvious choice is brightest towards Crux. The centre of the galaxy rises around 10PM. In it, Scorpius is now here called Manaia ki Te Rangi, the guardian of the sky, and if you're into jewelry, you’ll see that it looks like a manaia made of green stone - pounamu. It’s a beautiful name for Scorpius and is great that the asterism can look like so many things, including a scorpion - which here in New Zealand don’t exist.
    • Other visible galaxies are the Magellanic Clouds. Look for these in the Southern part of the sky, obviously, the part that we call circumpolar from here as the stars there never set and never rise but move around the celestial south pole in circles. Usually any star above declination -60 classifies as circumpolar from here.
    • There are a whole bunch of amazing galaxies around Leo at this time of year. For our northern hemisphere listeners, Leo in the southern hemisphere is upside down from what you’re used to. The most amazing of the group of galaxies is the Leo triplet, which is M66, M65 and NGC 3628, and it’s really amazing to see three of them in the eyepiece. If you’ve got a big enough telescope, you can always go a little better, up the sky to NGC 3593 and then a little bit further away to NGC 3596 which are two nice galaxies too. Also a little bit above Leo, there’s another bunch of galaxies, Messier objects M95, M96, and M105, and in fact round M105 there’s another couple of galaxies, NGC 3389 and NGC 3384 - they’re all quite easy to see. If you’ve got a big telescope, you can also have a look for four other galaxies that are closer to Leo than the three I just mentioned: NGC 3338, NGC 3367, NGC 3377 and NGC 3412. They are all pretty easy to find as well. NGC 3367, if you can catch that one, is a hundred and fifty million light years away, which is staggering.
    • Closer to the horizon, there’s all the galaxies that are around Virgo. They’re probably still a bit low for us, but by April if we stay up late enough there will be a beautiful bunch of galaxies to have a look through. That’s one of the great groups of galaxies that we share with the northern sky.
    • Also, one of the classics for us is the Sombrero Galaxy, absolutely magic to look through on the telescope. Then, there’s M83, which is the big spiral that we see down here in the southern hemisphere. There’s Centaurus A, also known as the Hamburger Galaxy, and there’s another great galaxy that we quite like looking at as well - it’s NGC 4945, which is just above Omega Centauri, between Omega Centauri and the Southern Cross.

    Binocular objects

    • Omega Centauri is a nice big globular cluster, really easy to see and you can totally spot that.
    • Now, if you’ve got a nice dark sky you’ll also be able to see M83 pretty easily in binoculars, so that’s definitely worth checking out. There’s not many galaxies you can see in binoculars, but M83 is one of them, and in summer you can see Sculptor, so now we’re sort of getting into the colder months M83 dominates.
    • Then there are the larger clusters, the Southern Pleiades you can look at, which is pretty amazing in the binoculars. Omicron Valorum is high in the sky, as is NGC 2516, the Southern Beehive, and of course if you’re looking at the Southern Beehive you probably also want to look at the other Beehive, M44 in Cancer, which is also an absolutely wonderful binocular object as well. M42, the Eta Carina nebula is always great, and the Wishing Well cluster stands out really well in binoculars as well. 47 Tucanae is the other really nice globular cluster to have a look at.
    • Of course what you can do as well is just lie on the ground with your binoculars and just browse around the Large Magellanic cloud. You’ll see the Tarantula nebula, and you might see a whole bunch of fuzzy-looking stars, which will be the big collection of globular clusters and other open clusters they have in that galaxy. So well worth having a look there, especially if you have a decent high-powered pair of binoculars, but still quite cool on small binoculars as well.

    So, from here from New Zealand, we wish you clear skies so that you can always see the stars, and stay safe - stay inside, keep your two metre distance from people, and don’t get sick. Clear skies, everyone, and let’s hear each other healthy next month.

    1 April 2020, 8:00 am
  • 18 minutes 31 seconds
    The night sky for March 2020

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during March 2020.

    Ian Morison tells us what we can see in the northern hemisphere’s night sky during November 2019.

    The Planets

    • Jupiter As March begins, Jupiter rises more than 90 minutes before the Sun shining at magnitude of -2. It then follows Mars and precedes Saturn into the pre-dawn sky - all rising within the space of an hour. During the month it brightens to magnitude -2.1 whilst its angular size increases from 34.2 to 36.9 arc seconds. A low south-eastern horizon will be needed and our views of the giant planet and its Gallilean moons will be hindered by the depth of atmosphere through which it will be observed.

    • Saturn At the start of March, Saturn rises at 05:33, half an hour after Jupiter, and, by its end, at 04:42 whilst its magnitude remains at +0.7 and it angular size increases from 15.5 to 16.1 arc seconds. Sadly, its low elevation before sunrise will limit our views of this most beautiful planet. Binoculars might be needed to spot it, but please do not use them after the Sun has risen.

    • Mercury Mercury is lost in the Sun's glare this month so cannot be observed.

    • Mars, Mars can be seen towards the southeast in the pre-dawn sky at the start the month. It then rises at ~04:30am and will be best seen at around 6am having an elevation of ~8 degrees. It will have a magnitude of +1.1 and a 5.5 arc second, salmon-pink, disk and lies just to the left of the 'lid of the teapot' in Sagittarius. By month's end it will have just moved into Capricornus and will be seen further round towards the south before dawn when its magnitude will have increased slightly to +0.8. Its angular size will have increased to 6.4 arc seconds but no markings will be seen with a small telescope. During the month it moves eastwards with respect to Jupiter and Saturn which had followed it into the pre-dawn sky as March began and passes below Jupiter on the 21st and Saturn as April begins.

    • Venus, Venus is now dominating the south-western twilight sky and appears higher each night until the 24th when it reaches greatest elongation east from the Sun and will then have an elevation at sunset of ~40 degrees - about the highest elevation it can ever achieve! During the month its angular size increases from 18.8 to 25.2 arc seconds but, at the same time, it phase (the percentage of the disk illuminated) decreases from 63% to 48% and so the brightness only increases slightly from -4.3 to -4.5 magnitudes.

    Highlights

    Early March - evening: Spot Uranus near Venus. A chance to find Uranus, at magnitude 5.8, with binoculars as it is approached by Venus. The chart shows the relative positions of Uranus and Venus during the first week of March. Uranus forms a 'propeller' with two other stars so should be easy to spot as Venus passes close by.

    March 8th - late evening: the near full Moon lies below Leo. In the late evening, the Moon, one day before full, lies below the belly of Leo, the Lion.

    March 18th - before Dawn: Three planets and a waning crescent Moon. If clear before dawn on the 18th, looking towards the southeast, one should see a waning crescent Moon down to the right of Mars, Jupiter and Saturn.

    March 28th/29th - early evening: Venus and a thin crescent Moon will be seen near the Hyades and Pleiades Clusters. If clear in the early evening of the 28th, Venus will be seen to the upper right of a very thin crescent Moon with both lying below the Hyades and Pleaides Clusters. On the following night, the crescent Moon will lie in the upper right of the Hyades Cluster Nice photo opportunities.

    March 31st - before Dawn: Saturn, Jupiter and Mars. If clear before dawn on the 31st, one will see a nice grouping of, from left to right, Saturn, Mars and Jupiter.

    March 15th evening: Mons Piton and Cassini Best seen close to third quarter, Mons Piton is an isolated lunar mountain located in the eastern part of Mare Imbrium, south-east of the crater Plato and west of the crater Cassini. It has a diameter of 25 km and a height of 2.3 km. Its height was determined by the length of the shadow it casts. Cassini is a 57km crater that has been flooded with lava. The crater floor has then been impacted many times and holds within its borders two significant craters, Cassini A, the larger and Cassini B. North of Mons Piton can be seen a rift through the Alpine Mountains (Montes Alpes). Around 166 km long it has a thin rille along its center. I have never seen it but have been able to image it as can be seen in the ‘8 day Moon’ part of the lunar section.

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during March 2020.

    16 March 2020, 3:00 pm
  • 59 minutes 18 seconds
    The night sky for February 2020

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during February 2020.

    The Planets

    • Jupiter As February begins, Jupiter rises more than 90 minutes before the Sun shining at magnitude of -1.9. During the month it brightens to magnitude -2.0 whilst its angular size increases slightly from 32.5 to 34.1 arc seconds. A low south-eastern horizon will be needed and our views of the giant planet and its Gallilean moons will be hindered by the depth of atmosphere through which it will be observed.

    • Saturn passed directly behind the Sun on the 13th of January and, as February begins, will rise less than one hour before the Sun. Then, equipped with binoculars and a very low south-eastern horizon, it might be glimpsed at magnitude +0.58 in the pre-dawn sky - but please do not use binoculars after the Sun has risen. As February progresses, its magnitude actually reduces very slightly to +0.66 as it angular size increases from 15.1 to 15.5 arc seconds. Saturn crosses the Ecliptic (the path of the Sun across the heavens) in a southerly direction on the 13th, just 13 days before Jupiter reaches this point whilst Mars reaches it on the 1st of February. (Stellariun shows them beautifully aligned along the ecliptic this month.)

    • Mercury passed in front of the Sun (superior conjunction) on the 10th of January and, on the 10th of February, comes to its greatest elongation east, some 18.2 degrees in angle from the Sun. Mercury starts the month at magnitude -1 and dims to magnitude +0.2 by the 14th and will then soon be lost in the Sun's glare. From the 1st to the 14th, its angular size increases from 5.6 to 8.1 arc seconds but its phase (the % illuminated disk) falls from 85% to just 32% - hence the fall in magnitude. On the 1st of the month, it will set about 70 minutes after the Sun and will have an elevation, low in the west-southwest, of ~9 degrees. This will increase until the 10th before it begins to fall back towards the Sun. Binoculars may well be needed, but please do not use them until after the Sun has set.

    • Mars can be seen towards the southeast in the pre-dawn sky at the start of the month. It then rises some three hours before the Sun and will be best seen at around 7am having an elevation of ~8 degrees. It will have a magnitude of +1.4 and a 4.3 arc second, salmon-pink, disk. By month's end it will be seen further round towards the south before dawn and its magnitude will have increased slightly to +1.1. Its angular size will have increased to 5.5 arc seconds but no markings will be seen unless you have access to the Hubble Space Telescope. Lying along the ecliptic it is moving eastwards above the 'Teapot' of Sagittarius and will lie just above its 'lid' on the 24th.

    • Venus is now dominating the south-western twilight sky and appears higher each night, climbing from ~29 degrees above the horizon to more than 38 degrees at sunset. During the month its angular size increases from 15.3 to 18.6 arc seconds but, at the same time, it phase (the percentage of the disk illuminated) decreases from 73% to 63% and so the brightness only increases slightly from -4.1 to -4.3 magnitudes.

    Highlights

    • February: find M31 - The Andromeda Galaxy - and perhaps M33 in Triangulum. In the evenings when the Moon is not prominent, the galaxy M31 in Andromeda will be visible high in the south. There are two ways of finding it:

      1) Find the square of Pegasus. Start at the top left star of the square - Alpha Andromedae - and move two stars to the left and up a bit. Then turn 90 degrees to the right, move up to one reasonably bright star and continue a similar distance in the same direction. You should easily spot M31 with binoculars and, if there is a dark sky, you can even see it with your unaided eye. The photons that are falling on your retina left Andromeda well over two million years ago!

      2) You can also find M31 by following the "arrow" made by the three rightmost bright stars of Cassiopeia down to the lower right.

      Around new Moon (23rd February) - and away from towns and cities - you may also be able to spot M33, the third largest galaxy after M31 and our own galaxy in our Local Group of galaxies. It is a face on spiral and its surface brightness is pretty low so a dark, transparent sky will be needed to spot it using binoculars (8x40 or, preferably, 10x50). Follow the two stars back from M31 and continue in the same direction sweeping slowly as you go. It looks like a piece of tissue paper stuck on the sky just a bit brighter than the sky background. Good Hunting!

    • February 3rd - evening: the Moon between the Hyades and Pleiads Clusters. In the evening one could see the waxing Moon, moving towards full, lying to the right of the Hyades Cluster. Aldeberan is a red giant star far closer to us than the Hyades.

    • February 7th - after sunset: Venus lies above Mercury. After sunset, low in the southwest, Venus will lie above Mercury. Venus will not be missed, but to spot Mercury which lies down to its lower right, a low horizon just south of west and perhaps binoculars will be needed - but please do not use them until the Sun has set.

    • February 18th - before dawn: a thin crescent Moon lies just to the right of Mars. If clear around 7 am on the 18th, one will see a thin cresent Moon lying over to the right of Mars. This could be a nice photo opportunity.

    • February 27th - after sunset: a very thin crescent Moon lies down to the lower left of Venus. After sunset on the 27th, and given a low horizon towards the west, you may be able to spot a very thin crescent Moon lying down to the lower left of Venus.

    • February 29th - before dawn: a lineup of Saturn, Jupiter and Mars. If clear around 6:30 am on the 29th, one will see a nice lineup of, from left to right, Saturn, Jupiter and Mars. A low horizon towards the southeast will be needed to spot Saturn.

    • February 1st and 14th evening: The Hyginus Rille. During these evenings the terminator lies close so making it more obvious. For some time a debate raged as to whether the craters on the Moon were caused by impacts or volcanic activity. We now know that virtually all were caused by impact, but it is thought that the Hyginus crater that lies at the centre of the Hyginus Rille may well be volcanic in origin. It is an 11 km wide rimless pit - in contast to impact craters which have raised rims - and its close association with the rille of the same name associates it with internal lunar events. It can quite easily be seen to be surrounded by dark material. It is thought that an explosive release of dust and gas created a vacant space below so that the overlying surface collapsed into it so forming the crater.

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during February 2020.

    19 February 2020, 3:00 pm
  • 35 minutes 48 seconds
    The night sky for January 2020

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during January 2020.

    The Planets

    • Jupiter passed behind the Sun on December 27th, 2019 and will be lost in the Sun's glare in the early part of January. But, by the middle of the month, it will become visible, shining at magnitude -1.9 in the pre-dawn sky and, by month's end, will rise about an hour before the Sun. A low eastern horizon will be needed and our views of the giant planet and its Gallilean moons will be hindered by the depth of atmosphere through which it will be observed.

    • Saturn passes directly behind the Sun on the 13th of January so could not be seen until the very end of the month. Then, equipped with binoculars and a very low eastern horizon, it might be glimpsed at magnitude 0.6 in the pre-dawn sky as it rises about 40 minutes before the Sun - but please do not use binoculars after the Sun has risen.

    • Mercury passes in front of the Sun (superior conjunction) on the 10th of January so will not be visible until the very end of the month. Then, at magnitude -1.0, it will set about 70 minutes after the Sun and will have an elevation, low in the west southwest, of ~9 degrees. Binoculars may well be needed, but please do not use them until after the Sun has set.

    • Mars can be seen towards the southeast in the pre-dawn sky at the start of the month. It then rises some three hours before the Sun and will be best seen at around 7am having an elevation of ~11 degrees. It will have a magnitude of +1.6 and a 4.3 arc second, salmon-pink, disk. By month's end it will be seen further round towards the south before dawn and its magnitude will have increased slightly to +1.4.

    • Venus rises rapidly in the twilight sky this month. As January begins, it could be best seen, shining at magnitude -4, at about 5 pm having an elevation of ~11 degrees above the south-western horizon. As the month progresses, remaining at magnitude -4, its elevation at sunset increases and will be best seen at about 6 pm having an elevation of ~22 degrees. During the month its angular size increases from 13 to 15 arc seconds but, at the same time, it phase (the percentage of the disk illuminated) decreases from 82% to 74% and so the brightness remains constant.

    Highlights

    • January, evening: the Double Cluster and the 'Demon Star', Algol. January is a good time to look high in the south after dark towards the constellations of Cassiopea and Perseus. Perseus contains two interesting objects; the Double Cluster between the two constellations and Algol the 'Demon Star'. Algol in an eclipsing binary system as seen in the diagram below. Normally the pair has a steady magnitude of 2.2 but every 2.86 days this briefly drops to magnitude 3.4.

    • January: find M31 - The Andromeda Galaxy - and perhaps M33 in Triangulum. In the evenings when the Moon is not prominent, the galaxy M31 in Andromeda will be visible high in the south. There are two ways of finding it:

      1) Find the square of Pegasus. Start at the top left star of the square - Alpha Andromedae - and move two stars to the left and up a bit. Then turn 90 degrees to the right, move up to one reasonably bright star and continue a similar distance in the same direction. You should easily spot M31 with binoculars and, if there is a dark sky, you can even see it with your unaided eye. The photons that are falling on your retina left Andromeda well over two million years ago!

      2) You can also find M31 by following the "arrow" made by the three rightmost bright stars of Cassiopeia down to the lower right.

      Around new Moon (24th January) - and away from towns and cities - you may also be able to spot M33, the third largest galaxy after M31 and our own galaxy in our Local Group of galaxies. It is a face on spiral and its surface brightness is pretty low so a dark, transparent sky will be needed to spot it using binoculars (8x40 or, preferably, 10x50). Follow the two stars back from M31 and continue in the same direction sweeping slowly as you go. It looks like a piece of tissue paper stuck on the sky just a bit brighter than the sky background. Good Hunting!

    • January 4th - before dawn: Mars lies above Antares in Scorpius. If clear before dawn on the 4th, one will see Mars (magnitide +1.55) just above the first magnitude red giant star Antares.

    • January 7th - evening: the Moon lies within the Hyades Cluster. In the evening one could see the waxing Moon, moving towards full, lying above Aldebaran in the Hyades Cluster. Aldeberan is a red giant star far closer to us than the Hyades.

    • January 10th - after sunset: Venus lies above Delta Capricornus. After sunset, low in the southwest, Venus will lie above the ~3rd magnitude star Delta Capricornus or Deneb Algedi.

    • January 27th - evening: a very thin crescent Moon lies between Venus and Mercury. If clear after sunset, looking towards the southwest one could see a very thin crescent Moon, just 3 days after New, lying below Venus and above Mercury.

    • January 7th and 24th: Two Great Lunar Craters These are two great nights to observe two of the greatest craters on the Moon, Tycho and Copernicus, as the terminator is nearby. Tycho is towards the bottom of Moon in a densely cratered area called the Southern Lunar Highlands. It is a relatively young crater which is about 108 million years old. It is interesting in that it is thought to have been formed by the impact of one of the remnents of an asteroid that gave rise to the asteroid Baptistina. Another asteroid originating from the same breakup may well have caused the Chicxulub crater 65 million years ago. It has a diameter of 85 km and is nearly 5 km deep. At full Moon the rays of material that were ejected when it was formed can be see arcing across the surface. Copernicus is about 800 million years old and lies in the eastern Oceanus Procellarum beyond the end of the Apennine Mountains. It is 93 km wide and nearly 4 km deep and is a classic "terraced" crater. Both can be seen with binoculars.

    Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during January 2020.

    Welcome to a new decade of astronomy, discovery and fun!

    Haritina Mogosanu and Samuel Leske from New Zealand have recorded a live observing session of the New Zealand's night sky.

    This month we look up into the night sky of January and February.

    We are actually at Stonehenge Aotearoa (New Zealand) in the middle of the night. To the south is the Southern Cross with the famous globular cluster Omega Centauri almost about to peer behind the tree, and then we can follow the Milky Way up past the asterisms of the Diamond Cross, the False Cross, Canis Major, Orion, then we have Taurus, the Pleiaides, or Matariki as we are calling these stars here, Aries, and that's the end of the Milky Way.

    This time of the year we can see only one spiral arm of our galaxy, the one we actually live in, the Orion Spur. Everytime we look towards Orion we look toward the edge of the galaxy. Every time we look towards Scorpius (which is now well beyond the horizon) we look towards the centre of our galaxy.

    This time of the year is also when we see very bright stars, not as many clusters and objects that are at the centre of the galaxy but still plenty in Carina Vela and Crux region here, all these objects are oldies but goldies and we still have the Magellanic Clouds to admire, they are very beautiful, especially under a dark sky like the one from Wairarapa.

    Stonehenge Aotearoa is located in the North Island of New Zealand in Wairarapa, which is one of the darkest locations in New Zealand.

    We decided to do something different this month and record live on this location from where we usually do our deep sky stargazing away from the light pollution of the big cities.

    With us we have the giant 16 inch telescope and we have been galaxy hunting all evening. The field of galaxies hunting is pretty amazing at the moment. In Grus, there is the Grus quartet, with four really bright galaxies; in Cetus there is Cetus A - we find about 5 galaxies around that one; in Fornax, if you follow the great Eridanus river around the sky, which goes from Orion's Rigel, all the way to Achernar here in New Zealand and is now at zenith, well up there are about 10 galaxies, at one point we had 6 galaxies simultaneously in the eyepiece. In terms of starhopping you will find these half way through between Rigel and Achernar, as you look towards Achernar from Rige, there are 4 stars looking like a parallelogram, to the left of those stars is a tiny little triangle and that's where you see these galaxies.

    We also decided to try out our narrow band OIII filter on the telescope and had a great look at Eta Carinae nebula and Tarantula nebula and browsed the Large Magellanic Cloud to see nebula after nebula. The filter makes a great difference to viewing.

    We are now going to move the large Leviathan telescope and look at the 47 Tucanae globular cluster, which is one of the greatest globular clusters in the southern hemisphere, here in New Zealand is located on the south circumpolar region; the nucleus of this globular cluster is very well defined. You can resolve the stars to the centre in the core and it almost looks tri dimensional.

    Now we look at Sculptor galaxy, which is a famous and easy-to-look-at galaxy here in the southern hemisphere. We can see the galaxy spanning across the entire eyepiece and fits in a very pointy triangle that also spans the length of the eyepiece almost perpendicular to the galaxy. Through the middle of Sculptor are four stars, another parallelogram.

    We will now try and find M1, the Crab nebula in Taurus, which also looks great with the OIII filter on. M1 is a wispy cloud remnant from a supernova explosion that occurred in 1054. Taurus is really high, and we can also see the Pleiades, Hyades and Aries on the northern horizon.

    In New Zealand, the stars of the zodiacal constellations shift slowly through the northern part of the sky and they move on the sky counter clockwise looking north, completely the other way around like in Europe. We can also see Orion that is upside down in the sky and from it we can observe the galactic arm stretching all the way to the Southern Cross where we can see with the naked eye the Flounder - or the Coalsack as we know it in Europe, the Flounder (Te Patiki) is the Maori name of this region of space where dust obscures the light that comes from the stars. Inside it, is the Jewel Box.

    The Magellanic clouds are very bright right now. Canopus is almost at Zenith, and we can make a line from Sirius, the brightest star in the sky to Canopus, the second brightest star in the sky, if you extend that line it will point towards the Large and Small Magellanic Clouds - the four objects are aligned.

    Back to the Crab Nebula it looked fluffy and beautiful. Hard to believe this was visible in the daytime for three weeks when the star went supernova in 1054. Close to it, we also observed Orion's nebula, a place where stars are born. In this telescope, M42 is very bright with the four stars of the trapesium being very clearly visible. We are also observing M78 that Sam believes is the forgotten cousin of M42 on which everyone focuses usually, but seeing this beautiful reflection nebula in M78 lit up by the brightest stars, you realise it's a great object on its own, and you can notice a dust line that stands out quite well.

    Next we look at Eta Carinae, just because it's so beautiful. We always visit this one. The dust lines are spectacular and there is a really crisp boundary between the nebula and the lines of dust. With the OIII filter, the nebula is very sharp. Close to it, the Wishing Well cluster (NGC 3532) is a massive collection of stars that fills the eyepiece, with almost equidistant stars, one of them is really bright, the cluster is almost resembling a snowflake. On the other side of the Carina Nebula, sitting almost straight on the Galactic Equator is Gem Nebula (NGC 3293). Both Gem and Wishing Well are objects located between the Southern Cross and the False Cross.

    The Gem Nebula is small and you can clearly see one red giant star, that stands out. It is a very beautiful cluster, that is similar to the Jewel Box but often overlooked because it's close to Eta Carinae.

    Same sky we look at now in January at midnight will be visible earlier and earlier throughout the month.

    We are now shifting to NGC 2546 in the Milky Way, just a bit away from the False Cross, a bit to the left of it, in Puppis.

    For the grand finale we looked at the really hard to see globular clusters in Musca, which now is almost at 2 o'clock from the Southern Cross. The sky is so clear that we can see Omega Centauri very easily with the naked eye. NGC 4833 is a lovely globular cluster about 6.9 magnitude where we can resolve stars to the centre, it has a tiny star at the side. Then we look at another fainter glob mag 7.2 NGC 3472, quite big and we can see the diffuse cloud-like smudgy pattern, but on top there are many stars we can resolve, a faint glob - compared to everything else we've been looking at.

    Next we go to another galaxy near Sculptor close to the star Deneb Kaitos. This one is a faint galaxy, elongated, pretty faint, and a few stars in front of it. NGC 247, a 9.1 spiral galaxy.

    Now we look for another glob, NGC 288, a magnitude 8.1 globular cluster visually just beyond sculptor galaxy. Very faint, surrounding it is a group of stars similar to Corona Borealis but the telescope version.

    Grus is now closing to the horizon, 10 degrees , with all its visually double stars, looking like a necklace.

    Tonight we have seen beautiful things in the sky and shared them and this amazing New Zealand night sky, where the milky way is so bright, it's been a great night, with more galaxies than you can poke a stick at, a really great night.

    Thank you to Stonehenge Aotearoa for letting us plant our telescopes in their field and to Rhian Sheenhan for the use of his amazing music - which we always listen to when we do observing.

    We wish you clear skies from New Zealand.

    Hari and Sam

    27 January 2020, 2:00 pm
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