Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 525 & 526: Collision & Tiny Visitor

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • 6478 Gault grew a tail when it hit another object in the asteroid belt. It’s likely a member of the Phocaea Family of asteroids.
  • Dr. Grauer discovered 2019 AS5, a 5′ diameter asteroid, after it passed inside our geostationary satellites.

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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525 – Collision

I was asteroid hunting with our 60 inch telescope on Mt. Lemmon, Arizona when my Catalina Sky Survey teammate Steve Larson sent me an email requesting that I obtain some images of the asteroid 6478 Gault.  Several days earlier, using mountain top telescopes in the Hawaiian islands , astronomers working with the ATLAS project reported that the perviously normally appearing asteroid 6478 Gault now has a 250,000 mile long straight tail.  I added together four 60 second images which revealed a point of light with a tail which appeared to be similar to a long straight contrail left by a jet airplane high above the Earth. Images taken of 6478 Gault over the past several months suggest that it hit another object in the asteroid belt. If this idea is correct the collision fragments are what are giving this asteroid its long thin tail.

Asteroid Gault is approximately 2.3 miles in diameter and thought to be a member of the Phocaea [Pho e ah] Family of main belt asteroids which themselves were formed by a violent collision about 2.2 billion years ago.  This swarm of 2,000 space rocks , orbit the Sun  once about every 3.5 years, between Mars and Jupiter.  The object which the 2.3 mile diameter Gault hit is likely to have been a third of a mile diameter space rock.  

526 – Tiny Visitor

Recently I was observing in the constellation of Cancer with the Catalina Sky Survey 60 inch telescope on Mt. Lemmon, Arizona when a rapidly moving object appeared in one of my sets of images.  I immediately posted the discovery observations on the Minor Planet Center’s, Near Earth Object Confirmation Page.  The NASA Scout Computer software system analyzed these observations and concluded that this object was on a close encounter path with planet Earth.  Telescopes in Arizona, Hawaii, and Tenerife obtained additional data.  

Scientists at the Minor Planet Center used these data to calculate the new objects orbit about the Sun, estimated its size to be about 5 feet in diameter, and give name 2019 AS5.  Turns out that 7h 53m 17s before I spotted it, 2019 AS5 had passed through the cloud of communication satellites surrounding the Earth at a distance of only 5,344 miles from humanity.  This small space rocks was accelerated by the Earth’s gravity which flung into a new, different path about the Sun.  Approximately once a month an object the size of 2019 AS5 enters the Earth’s atmosphere, bursts into fragments at an altitude of 150,000 feet, does not make much of a sonic boom, is seen as a brilliant fireball meteor, and scatters bits of itself on to the Earth’s surface for meteor hunters to discover.

For Travelers in the Night this is Dr. Al Grauer

End of podcast:

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