Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 631 & 632: Greg’s Comet & Couch Potato

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s two stroy:

  • Greg Leonard discovered C/2021 A1 (Leonard) in the constellation Canes Venatici.
  • Richard Kowalski 750’ diameter asteroid 2021 CK2 while sitting on his living room couch! 

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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631: Greg’s Comet

My Catalina Survey Teammate Greg Leonard was asteroid hunting  with our 60 inch telescope on Mt. Lemmon, Arizona when he spotted a fuzzy object with a short tail moving through the constellation Canes Venatici.  For 143 hours after Greg reported his observations to the Minor Planet Center his discovery was imaged and tracked by 14 telescopes at observatories around the world. Interestingly for the previous 9 months, Greg’s new comet had been tracked as a moving point of light and reported 16 times by observers to be an asteroid.  It was Greg’s luck and skill that enabled him to notice when this comet started to give off a cloud of gasses as it approached the Sun.  Using all available data astronomers were able to calculate its orbit about the Sun, and give it the name C/2021 A1 (Leonard).  

Greg’s first observations were made when C/2021 A1 (Leonard) was approaching from above the plane of the solar system 459 million miles from Earth.  In December of 2021 Comet Leonard will come closest to Earth on its way to zip around the Sun in January of 2022.   In January of 2041 comet C/2021 A1 (Leonard) will cross Pluto’s average distance from the Sun on a path which will take it into deep interstellar space never to return.   It is really hard to predict a comet’s maximum brightness.  That Greg spotted it some 472 million miles from the Sun leads us to believe that it may brighten to the point that C2021 A1 (Leonard) will be visible in binoculars and perhaps even to the naked eye.  

632: Couch Potato

My Catalina Sky Survey teammate Richard Kowalski is the first person in our group and perhaps the first person in the world to discover a potentially hazardous asteroid while sitting on his living room couch.  The COVID-19 pandemic has reduced the number of people who are allowed to be at the observatory at one time.  Thus Richard found himself operating our Schmidt telescope on Mt. Bigelow, Arizona with his laptop from his living room couch in Tucson, Arizona.  He programmed the telescope to begin taking images in the constellation of Eridanus and was delighted when a very bright fast moving object appeared in 3 of them.  After Richard submitted his observations to the Minor Planet Center his new object was observed by telescopes in Arizona, New Zealand, Chile, and Hawaii.  

Astronomers used these data to calculate its 4.27 year long orbit about the Sun, estimate it to be 750 feet in diameter, and give it the name 2021 CK2.  Fortunately on its current path 2021 CK2 never comes closer than about 10 times the Moons distance from us.  According to the Purdue University and Imperial College of London’s impact calculator,  a space rock the size of 2021 CK2 enters the Earth’s atmosphere every 59,000 years  and makes a crater 2 miles in diameter and 1300 feet deep in sedimentary rock.  Not to worry  2021 CK2 will not come very close to humanity till January of 2129 AD when it will pass about 16 times the Moon’s distance from planet Earth.

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

End of podcast:

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