Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps.99E & 100E: Green Meteors & A Banner Year For Asteroid Hunters

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • Recently, my wife and I saw a beautiful, bright,  green, meteor fireball streaking across the western New Mexico night sky.
  •  In 2014 asteroids hunters discovered more than 1,450 Earth approaching objects making it the most productive year yet.

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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99E: Green Meteors

Recently, my wife and I saw a beautiful, bright,  green, meteor fireball streaking across the western New Mexico night sky. Such sightings by some UFO enthusiasts , have been advanced as the best observations of alien spacecraft.  Other observers have explained this phenomena as being sightings of secret American or Russian spy devices.

In reality, a fireball meteor is a beautiful natural phenomenon. Its appearance is related to the color response of the human eye, the elements the meteor has brought to Earth, and its speed. Only about 1/20th of the light emitted from a fireball and its trail come from the atoms vaporized from the meteoroid. The rest of the light it produces comes from energized atoms in our atmosphere. Emission lines from iron, magnesium, sodium, manganese, chromium, copper, and other elements have been identified in the spectrum of colors given off by fireballs. 

You can expect to see a fireball brighter than the planets Mars or Jupiter every 20 hours or so.   The date and time you observe it along with your estimates of its brightness, path, and visual appearance are of scientific interest and should be reported to the American Meteor Society using its on-line form.     If your sighting is within the range of the NASA Fireball network you may be able to see it recorded  there.

Not long ago, a bright fireball entered the Earth’s atmosphere over San Antonio, Texas.  It reached a peak brightness of greater than the full moon.   There was a report from the Maverick County Sheriff’s Office that an impact was felt at  the time the fireball was observed. 

100E: A Banner Year For Asteroid Hunters

In 2014 asteroids hunters discovered more than one thousand four hundred and fifty Earth approaching objects making it the most productive year yet.  Both the Pan-STARRS group in Hawaii and my team, the Catalina Sky Survey each found more than 600 Earth approaching asteroids. 

In 2014, ninety three asteroids were marked as Potentially Hazardous since they are large enough and can come close enough to us for the asteroid hunting community to keep special track of them. We now know of more than 1500 Potentially Hazardous Asteroids.  Fortunately none of them will collide with planet Earth for hundreds of years, if ever.

2015 promises to be an even more productive year for the discovery of near Earth objects.  My group, the Catalina Sky Survey is scheduled to increase the field of view of our 60 inch telescope 4 fold.  We are upgrading the computing equipment and software since we will now be looking at fields containing more than 8 million stars and tens of thousands of known moving objects per night  to find the small number of new Earth approaching objects in these  data.

The goal of the NASA Near Earth Object Program is to discover any objects on a collision course with planet Earth.  We now know of more than 90% of objects whose impact could cause global climate change.  None of them is a current threat.  A more likely problem are the millions of small space rocks which come near to us. We are working on creating the ability to give a tornado like warning for people to stay away from doors and windows should one of them be about to enter our atmosphere. 

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

End of podcast:

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