Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 585 & 586: Mini Moon II & Northern PHA

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  •   Kacper Wierzchos & Teddy Pruyne were asteroid hunting in the constellation of Virgo and discovered 2020 CD3, a temporary natural Earth satellite.
  • David Rankin was observing in the constellation of Ursa Major and discovered 678’ diameter 2020 FH2.

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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585: Mini Moon II

My Catalina Sky Survey teammates Kacper Wierzchos (calfer wiz-joyce) and Teddy Pruyne (Teddy Pr i ne) were asteroid hunting in the constellation of Virgo with our 60 inch telescope when they spotted a faint fast moving object streaking through the night.  Observations by telescopes around the world caused scientists to suspect the new object to be a discarded lunar module or a small abandoned rocket stage.  Additional observations refining its track among the stars allowed astronomers to calculate its orbit, give it the name 2020 CD3, and identify this human being sized object to be a natural Earth satellite.  Apparently in June of 2019, 2020 CD3 passed at just the right distance and speed from the Earth and our Moon to be temporarily captured by the Earth’s gravity and become a natural Earth satellite.  Since that time this temporary mini moon has made at least 3 large looping orbits with periods from 70 to 90 days.  

In March of 2020, 2020 CD3 ends its temporary close dance with our home planet and resumes an orbit about our Sun.  This temporary capture of an asteroid is rare.  Another such 2006 RH120, discovered by my team captain Eric Christensen, was observed to make a few loops about Earth before resuming its journey about the Sun about a year later.  Scientists predict there are hundreds smaller than softball sized and perhaps several dozen football to beachball sized, natural Earth mini moons, which have so far evaded detection.  Stay tuned.

586: Northern PHA

My Catalina Sky Survey teammate David Rankin was observing in the constellation of Ursae Major with our 60 inch telescope on Mt. Lemmon, Arizona when he spotted a rare fast moving point of light in the night sky.  He was surprised by this discovery since it was made far north of the area in the sky  which contains the planets and most of the asteroids.  For the 10 days after David reported his observations to the Minor Planet Center his discovery was tracked by 17 different telescopes around the world.  Scientists at the Minor Planet Center used these data to calculate its 893 day orbit about the Sun, estimated it to be 678 feet in diameter, and give it the name 2020 FH2.  Although 2020 FH2 can come to within 11 times the moon’s distance from us, as it crosses the orbits of Earth and Mars, it will not come this close in the foreseeable future.  In the far distant future 2020 FH2 is likely to collide with Earth, our Moon, or Mars.  

According to the Purdue University and Imperial College of London’s impact calculator, approximately once every 24,000 years an asteroid the size of 2020 FH2 enters the Earth’s atmosphere, strikes the surface in a broken condition at a speed of 4.3 miles per second, and creates a crater 1.3 miles in diameter and 1,400 deep in sedimentary rock. If you were 25 miles away you would be covered with fine dust mixed with an occasional 5.5 inch diameter fragment.  Such an event has a probability less than your chances of winning the power ball lottery.

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

End of podcast:

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