Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps.  577 & 578: Comet Fuls & First PHA

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • Carson Fuls discovered C/2019 Y2 (Fuls), a Jupiter family comet, in the constellation Leo.
  • Greg Leonard discovered 2020 AD3,the first potentially hazardous asteroid of 2020, in the obscure constellation of Crater.

Bio: Dr. Al Grauer is currently an observing member of the Catalina Sky Survey Team at the University of Arizona.  This group has discovered nearly half of the Earth approaching objects known to exist. He received a PhD in Physics in 1971 and has been an observational Astronomer for 43 years. He retired as a University Professor after 39 years of interacting with students. He has conducted research projects using telescopes in Arizona, Chile, Australia, Hawaii, Louisiana, and Georgia with funding from NSF and NASA.

He is noted as Co-discoverer of comet P/2010 TO20 Linear-Grauer, Discoverer of comet C/2009 U5 Grauer and has asteroid 18871 Grauer named for him.

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577: Comet Fuls

My Catalina Sky Survey teammate Carson Fuls was asteroid hunting in the constellation of Leo when he spotted a faint fuzzy looking object with a tail moving through the night sky.  After Carson reported his observations to the Minor Planet Center, for nearly a month, his discovery was imaged and tracked by astronomers at 31 different observatories around the world.  Scientists at the Minor Planet Center used these observations to calculate this new object’s 6.5 year long orbit about the Sun, give it the name P/2019 Y2 (Fuls), and classify it as a Jupiter family comet.  

Traveling between the orbits of Mars and Jupiter Carson’s discovery is losing its trapped frozen gases as it continues to be warmed by the distant Sun.  Comet C/2019 Y2 (Fuls) must have been placed in its current orbit recently otherwise it would have already lost its volatile materials and be indistinguishable from the countless number of other small objects in the asteroid belt.  In a recent study published in the Astrophysical Journal Letters astronomers report the discovery of a gravitational comet gateway which funnels small icy solar system bodies called Centaurs from their orbits out near the planets of Saturn, Uranus, and Neptune into the inner solar system where they become Jupiter family comets like Carson’s discovery.  These scientist’s study suggests that in the next few thousand years such a process could produce a comet 10 to 100 times more active than Halley’s comet and be visible, to the humans who survive global warming, every 10 years or so.

578: First PHA

My Catalina Sky Survey Teammate Greg Leonard was observing in the obscure constellation of Crater with our Schmidt telescope on Mt. Bigelow, Arizona when he discovered the first potentially hazardous asteroid of 2020. Greg’s discovery, now called, 2020 AD3 is a 500 foot diameter space rock which crosses the orbits of Mercury, Venus, and Earth as it makes a trip about our Sun once every 356 days. Fortunately on its current path , 2020 AD3, never comes closer than about 6 times the Moon’s distance from us and is no threat to the human population.

Before Greg joined our asteroid hunting team he traveled around planet Earth searching for minerals which contain valuable metals. This experience got Greg to wondering what an asteroid like 2020 AD3 might be made of and if it could prove interesting as a source of precious raw materials. Assuming 2020 AD3 has a chemical composition similar to the stony meteorites we find on Earth, it could contain about a million metric tons of metals like iron, nickel, platinum, gold, and other rare minerals and be worth 2.6 billion dollars on the terrestrial metals market. The cost of lifting metals to low Earth orbit and/or bringing them to Earth’s surface may become as low as $2,500 per kilogram with the SpaceX Falcon 9. This suggests that in 60 years or so humans may look to asteroids as a source of precious metals when the easily accessible terrestrial supply becomes insufficient for our high tech needs. 

For Travelers in the Night this is Dr. Al Grauer.

End of podcast:

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