Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 179E & 180E: Two Odd Fellows & WISE Alive

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • Dr. Grauer discovered 2015 SY which orbits the Sun in only 321 days and 2015 SZ orbits the Sun every two and a half years.
  • NASA’s WISE spacecraft  discovered a rather interesting potentially hazardous asteroid named 2015 RR150.

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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179E: Two Odd Fellows

Recently I was lucky to be able to use the Catalina Sky Survey Schmidt telescope on Mt. Bigelow, Arizona for about 7 hours during a clear hole between storms.  This brief period on the sky yielded 7 new objects which were posted on the Minor Planet Center’s discovery page.  Fortunately telescopes around the world were able to make followup observations of these objects since the next thing we got in Arizona was a major rain event.

The two most interesting asteroids in this lot of 7 could be placed on top of each other under the St. Louis arch. 

2015 SY orbits the Sun in only 321 days.  In the next 50 years it will make 21 close approaches to Earth, 6 to Venus, and 2 to Mercury. Sometimes 2015 SY can come to about 3 times the Moon’s distance from us as it cruses the inner solar system.
2015 SZ orbits the Sun every two and a half years.  This asteroid’s path takes it from near Earth’s orbit to about halfway to Jupiter before it heads back towards the Sun again.  It came close to the Earth in 1933 and 2015 but will not do so again for several hundred years. 2015 SZ’s path never brings it closer than about 14 times the Moon’s distance as it orbits the Sun between Earth and Jupiter. 

Fortunately neither of these will enter the Earth’s atmosphere in the foreseeable future since they are both capable of producing a city destroying air blast.

180E: WISE Alive

When the NASA WISE spacecraft ran out of frozen hydrogen, its detectors warmed up, and it was no longer able to conduct its primary mission.  It was placed in a hibernation mode and left to orbit the Earth in silence.  A couple of years ago NASA engineers figured out that the spacecraft, even with warm detectors, could find some interesting asteroids and decided to wake it up. The WISE spacecraft in turn has produced data on more than15,000 solar system objects including more than 350 Earth approaching asteroids and 60 comets.

Recently the repurposed NASA WISE spacecraft  discovered a rather interesting potentially hazardous asteroid named 2015 RR150.  Least you get worried this 1300 foot diameter asteroid’s current path never takes it closer than 9 times the Moon’s distance from us.  What makes this asteroid interesting is that its orbital path takes it way out of our solar system’s plane where almost every other object orbiting the Sun travels. It must have an interesting story to tell.

Perhaps, 2015 RR150 is related to the so called Euphrosyne (pronounced you-FROH-seh-nee) asteroids which were created by one of the last great collisions in our solar system some 700 million years ago.  This family asteroid’s members do not reflect much sunlight and have orbits which are highly inclined to the solar system’s plane.

It is important for humans to discover and study the family of low reflectivity asteroids related to 2015 RR150 so that one of them does not sneak up on planet Earth.

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

End of podcast:

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