Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 619 & 620: Apophis Campaign & Interstellar Travelers

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • To test techniques for characterizing a newly discovered PHA, scientists were planning to treat Apophis as an unknown object when it became detectable last year.
  • The discovery of two objects, Oumuamua & Comet Borisov, have demonstrated that inanimate objects can make such a voyage.

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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619: Apophis Campaign

Currently scientists, governments, and private citizens are preparing to mitigate a disaster caused by a large incoming space rock.  Action plans include the possibly of pushing on the asteroid to make it miss as well as mass evacuations and other civil defense measures should all else fail.  This comprehensive effort requires that humans  learn as much as possible about the potential impactor’s size, mass, chemical composition, and moment of impact.  

From previous observations,  we know that the aircraft carrier sized asteroid Apophis will come extremely close to Earth without hitting our planet in 2029, 2036, and 2068.  Apophis’s  323.6 day path about the Sun rarely brings it near enough for asteroid hunter’s to detect.  To test  techniques for characterizing a newly discovered potentially threatening asteroid, scientists are planning to treat Apophis as an unknown object when it becomes detectable to Earth bound telescopes in 2020-2021.   In order to make this drill work asteroid hunters are asked to consider Apophis to be an unknown object  which scientists then carefully track and characterize to discover from scratch its orbit, size, shape, rate of spin, and chemical composition.  In the vast majority of cases as our knowledge of a newly discovered  asteroid increases the chances that it will impact Earth vanish to zero.  On the other hand in this drill,  the more we learn about Apophis in 2020 and 2021 the more it will appear likely to impact Earth. The results of this simulation will prepare us for the day when asteroid hunters find the big one with our number on it.

620: Interstellar Travelers

For millennia humans have gazed into the night sky and have dreamed of traveling to the stars.  The discovery of two objects, Oumuamua  and Comet Borisov, streaking through our solar system, have demonstrated that inanimate objects can make such a voyage,  In a recent scientific paper two Harvard University Astronomers point out that the Vera C. Rubin Observatory’s Legacy Survey of Space and Time is likely to discover such interstellar celestial visitors as often as once a month.  By studying the distribution of speeds and physical characteristics of these interstellar travelers in the night scientists will be able to better understand how planets form in other solar systems.  Here on Earth scientists funded by project Breakthrough Starshot are currently planning to send tiny laser and light sail  propelled spacecraft to visit the nearby solar system Alpha Centauri.  

In a recent scientific  paper Dr. Kevin Parkin the Systems Director for Breakthrough Starshot outlines how a tiny space probes can transmit  data through the vast distance between stars.  This process offers the hope that someday  humans will receive first hand knowledge of the nature of planets in a neighboring solar system.   It is not beyond the realm of possibility that one of the objects astronomers

 discover passing through our solar system was created and is operated by an advanced technological life form in the Milky Way.  Until then we can look into a natural night sky such as one can find at the Cosmic Campground International Dark Sky Sanctuary in New Mexico and wonder what is out there.

End of podcast:

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