Travelers In The Night

Dr. Al Grauer

Space, Asteroid Hunting, and Astronomy, an insider view. The music is "Eternity" by John Lyell. Astronomy Asteroids Space NASA Comets Earth Impact

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    370E-403-Double Comet
    In November of 2006, University of Arizona's Spacewatch astronomers on Kitt Peak discovered a faint moving point of light in the night sky which appeared to be a garden variety main belt asteroid orbiting the Sun between Mars and Jupiter. The Minor Planet Center calculated it's orbit and gave it the name 2006 VW139. Five years later when it again moved closest to the Sun the Pan-STARRS group in Hawaii discovered that 2006 VW139 is surrounded by a gas cloud like a comet and it was given a comet designation, 288P. My Catalina Sky Survey teammate Steve Larson is a member of the team of astronomers who use the Hubble Space Telescope to observe asteroids which have comet like burps. Observations by the Hubble Space Telescope between August 2016 and January 2017 clearly show 288P to be two similar, mile diameter, asteroids orbiting each other about 60 miles apart, surrounded by a gas cloud, as they move about the Sun. The Hubble team estimates that about 5,000 years ago this strange object was formed when a rapidly rotating comet nucleus came apart into two large pieces. It's gas cloud is likely to come from volatile ices like carbon dioxide and water vapor which were liberated by solar heating. Objects like this one are very interesting since they may have had a role in bringing water to a bone dry Earth in the early days of our solar system.
    6 January 2026, 4:00 pm
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    882-David’s Goliath PHA
    My Catalina Sky Survey teammate David Rankin was asteroid hunting in the evening twilight with our 60 inch telescope on Mt. Lemmon Arizona when he spotted an unknown object in the constellation of Lyra. The largest telescopes on Earth will likely track David's discovery until it becomes too faint to observe in 2027 and catch it again when it again becomes bright enough to track in 2050. Fortunately it is extremely unlikely that it will strike Earth when it again comes close to our home planet in 2052.
    2 January 2026, 4:00 pm
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    369E-401-Night Vision
    Many people in our modern world rarely if ever experience night vision. To achieve this interesting state of sensory awareness you cannot look at your cell phone or any other source of bright light for 30 to 45 minutes. Your night vision comes about over time because the rod sensors in the retina of your eye undergo a chemical change when they are placed in total darkness. The process starts immediately but takes 20 to 30 minutes to get 80% of maximum sensitivity. The night vision process can be reversed in seconds by exposure to a bright light. In it's most sensitive state your eye can function with a billion times less light than is present in strong sunlight enabling you to see a candle flame from 1.6 miles away.
    30 December 2025, 4:00 pm
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    881-Dangerous Comets
    It is possible the object creating the Tunguska event in Russia 1908 which knocked down 80 million trees over an area about twice the size of New York City was a fragment of a comet or asteroid. The International Asteroid Warning Network 2025 campaign to track Comet 3L/Atlas prepares the worlds observatories for the eventual time when a comet fragment has our number on it.
    26 December 2025, 4:00 pm
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    368E-400-Roving Venus
    Venus and Earth are similar in size, composition, density, and mass. Unfortunately, our sister planet Venus is an example of a place where green house gases have created an extreme situation. Venus's thick carbon dioxide atmosphere has a surface pressure 90 times that of Earth. It would crush a submarine. Additionally, the thick atmospheric blanket holds in the heat causing Venus's surface temperature to be 864 F, hot enough to melt lead.
    23 December 2025, 4:00 pm
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    880-Carrington Anticipated
    Just before noon on September 1st of 1859 Richard Carrington and Richard Hodgson were making sketches of clusters of sunspots when they were nearly blinded by an intense solar flare. 17.6 hours later a geomagnetic storm thought to be caused by a solar coronal mass ejection traveling at some 1,500 miles per second slammed into the magnetic field surrounding our home planet. We missed being hit with a such large coronal mass ejection by only 9 days in July of 2012. Next time we might not be that lucky.
    19 December 2025, 4:00 pm
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    367E-399-Moons of Florence
    Dr Lance Benner of NASA's Jet Propulsion Laboratory headed up a team of scientists who used the 70 meter antenna at NASA's Goldstone Deep Space Communications Complex to bounce RADAR beams off of the asteroid Florence as it made a close approach to Earth in September of 2017. The RADAR images these researchers obtained reveal that Florence consists of a 2.8 mile diameter primary asteroid which is orbited by two small moons. Florence's two satellites appear to be between three hundred and a thousand feet in diameter and orbit the main asteroid in about 8 and 24 hours respectively. Florence is rare since there are only two other triple asteroid systems among the 16,000 Earth approaching asteroids which asteroid hunters have discovered. We would know more about Florence if Hurricane Irma had not prevented astronomers from using the giant Arecibo RADAR Dish in Puerto Rico to study it. Our curiosity will have to wait since Florence will not come very close again until September 2, 2057.
    16 December 2025, 4:00 pm
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    879-Lurking Asteroid
    The Dark Energy Camera on the National Science Foundation’s Blanco 4-meter telescope on Cerro Tololo in Chile is taking near Sun twilight images to search for asteroids, hidden in the glare of our Sun, sneaking up on home planet.
    12 December 2025, 4:00 pm
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    366E-398-Mars Rocks
    At about 2AM on July 18, 2011 several people in near Tata, Morocco saw a bright fireball which was described by one of them to be initially yellow, then turned green, and finally exploded into several pieces producing two sonic booms. In October of 2011 desert wandering nomads began finding very fresh looking dark fusion-crusted stones which were radioactively dated by Dr. John Duke of the University of Alberta to be less than 5 years old. In total 15-24 lbs of meteorites consistent with a very recent fall were found in a strewn field, were whisk away to receive high prices from collectors, and named after the town of Tissint [tee.seent] about 30 miles from their discovery location.
    9 December 2025, 4:00 pm
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    878-Comet Fragment
    My Catalina Sky Survey teammate Vivian Carvajal was asteroid hunting in the constellation of Eridanus with the 90 inch, University of Arizona’s Bok telescope on Kitt Peak when she was treated to an amazing sight. Comet COMET 240P/NEAT with a small version of itself cruising along beside it.It is virtually impossible to predict if Vivian’s fragment 240P-B will survive to make another approach to the Sun in 2033 or so.
    5 December 2025, 4:00 pm
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    365E-397-Spotting Meteors
    Meteors, shooting stars, or falling stars are different names for the streaks of light in the night sky which are in reality the dying embers of tiny asteroids. These small interplanetary travelers were speeding along at between 7 and 44 miles per second when they entered the Earth's atmosphere. In space, they are called meteoroids and typically ranged in size from that of a grain of sand to perhaps ones as big as of a piece of driveway gravel. Large space pebbles can produce fireballs which are brighter than the planet Venus. Most meteors burn up 50-70 miles above you, however, a very few of them produce fragments which fall to the Earth's surface. In rare occasions meteor observers are able to walk up to such a fallen space rock which is called a fall. The best time to view meteors is generally after midnight on a clear, moonless night. You will see many more meteors in a rural area than under city lights. On nights not during a meteor shower, you may expect to view sporadic meteors at the rate of between 2 and 16 per hour. Some meteor showers produce more than 100 events per hour. Rarely you will have a chance to view a meteor storm which will give you the feeling that you are seeing the Earth move through space. In 1966 one of these storms produced a WOW inspiring 40 meteors per second. During the year, there are a dozen major meteor showers. Check out the International Meteor Organization Calendar for a complete listing of the dates of meteor showers as well as how bright the moon will be on those dates. Happy viewing.
    2 December 2025, 4:00 pm
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