Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 561 & 562: Hannes Is Back & Monster Space Roc

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • Hannes Groeller discovered 7 new Earth approaching asteroids in a single night.
  • Hannes Groeller discovered giant half-mile diameter 2019 RU3.

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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561: Hannes Is Back

During the monsoon rainy season, my Catalina Sky Survey teammate, Hannes Groeller took a vacation in his native Austria.  There, he visited friends and family,  paddle boarded on a lake, and hiked in the alps,  spending 3 nights in wooden huts at high altitude.  Returning to begin the fall season of observing with our Schmidt  Telescope on Mt. Bigelow, Arizona,  Hannes discovered 7 new Earth approaching asteroids in a single night.  

Hannes also rediscovered a football sized asteroid, 2006 SE6 which had been in hiding near our Sun. On Hannes’s record breaking night the only one of his space rocks which comes very close to the planet Earth is the 13 foot diameter 2019 QQ3.  14 hours before Hannes caught it streaking through the constellation of Aquarius, this tiny space rock escaped burning up in our atmosphere by only 59,000 miles.   On its current path about the Sun,  it crosses the orbits of both Earth and Venus.  2019 QQ3 will not come so close to Earth again until 2083, however, it is very likely to strike the Earth or the Moon sometime in the far distant future. Not to worry.  One the size of 2019 QQ3 enters our atmosphere approximately 3 times a year, bursts into a cloud of fragments at about 157,000 feet, and releases the energy of 170 tons of TNT.  

If your were fortunate to witness such an event at night you would be treated to a silent but spectacular light show. 

562: Monster Space Rock

While observing with our 60 inch telescope on Mt. Lemmon, Arizona, my Catalina Sky Survey teammate Hannes Groeller discovered a giant half mile diameter space rock streaking through the constellation of Orion.  After that it was  tracked by telescopes in Arizona, Illinois, Pennsylvania, England and Tican.  Scientists at the Minor Planet Center used these data to calculate this space rock’s path about the Sun, estimate its size, and give it the name 2019 RU3.    

An object the size of 2019 RU3 enters the Earth’s atmosphere every 180,000 years with an energy of 5,800 megatons of TNT.  Such an impactor begins to break up at an altitude of 215,000 feet, strikes the ground in a broken condition, and forms a crater 4.6 miles in diameter and 1,800 feet deep.  25 miles from impact the area would be bombarded by 20 inch diameter fragments and the ground would shake like a 7.1 magnitude Earthquake.  At this distance, buildings would collapse, 90% of the trees would be blown down, and highway truss bridges would collapse.  The only place to survive would be in an underground bunker.  Fortunately Hannes’s discovery, 2019 RU3 will not strike the Earth in the foreseeable future.  Rest assured that asteroid hunters will continue to track this monster space rock to be sure it does not change path and become a danger to humanity as it crosses the orbits of Mercury, Venus, Earth, and Mars.

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

End of podcast:

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