Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 171E & 172E: No Worries & Most Dangerous

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • There’s a false rumor that there is an asteroid which is about to strike the Earth producing catastrophic damage. 
  •  2015 PU228 is currently the asteroid which is most likely to collide with planet Earth in this century. January 15, 2081 to be exact. 1/23,000 chance of impact.

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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171E: No Worries

A number of blogs and postings on the web have been spreading the false rumor that there is an asteroid which is about to strike the Earth producing catastrophic damage. There are also recurrent false rumors that the government or governments are hiding the fact that a catastrophe is about to occur. Neither of these has a shred of evidence to back them up.

Asteroid hunting is an open book.  When my group, the Catalina Sky Survey, finds a potentially new Earth approaching object,  we post our observations on a public website at the International Astronomical Union’s Minor Planet Center. Other observatories and individuals, around the world,  use our posting to observe this potentially new object. In about 72 hours the new object’s orbit is sufficiently established so that astronomers will be able to identify it when they observe it moving through the night sky.  Then the Minor Planet Center gives it a name.  If the newly discovered asteroid or comet is found to have remote chance of striking the Earth in the next 100 years or so it is, posted on the NASA/JPL Sentry Impact Risk Page.  There the odds of the, so far, extremely remote possibility that an object will strike are listed for all to see.  In every case to date, additional observations continue to reduce the chances that a particular object will impact mother Earth.

A recent find, 2015 PU228, has been predicted to come to within less than an Earth radii of us in January of 2081. The asteroid hunting community will continue to monitor this object to make sure than it’s orbit does not change to make it an impactor as encounters other objects in space. 

172E: Most Dangerous

Recently the  3.5 meter Space Surveillance Telescope located at the White Sands Missile Range in New Mexico found an an asteroid which has been named 2015 PU228. It is currently the asteroid which is most likely to collide with planet Earth in this century.  Don’t worry, its closest approach to our home planet will not be until January 15, 2081.  

Currently 2015 PU228 has a one in 23,000 chance of impacting Earth more than 60 years from now. Since 2015 PU228 is about 4 football fields in diameter, could strike the Earth at a speed of 17 miles per second, and packs a potential impact energy of 4,000 million tons of TNT it has jumped to the top of the list of asteroid hunter’s concerns.  An object of 2015 PU228’s size probably strikes the Earth every 100,000 years or so making an impact crater 3 or 4 miles in diameter.

If there is an ideal close approaching asteroid, 2015 PU228 is it.  Humans have discovered this object long before it comes near to our home giving plenty of time to deflect it if that becomes necessary.  Serious scientific and engineering studies are currently underway to investigate various asteroid impact mitigation strategies.  These range from using a solar sail to give the problem asteroid a gentle push to setting off a buried nuclear weapon to create a rocket type thrust which will cause the potential impactor to miss planet Earth.

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

End of podcast:

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