Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps 649 & 650: 30 Days of Traffic & Jupiter (396)

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s two stroy:

  • 2021 KT1 is 750 feet in diameter & is a PHA.
  • In terms of the defense of planet Earth from impacting objects, Jupiter is a mixed blessing.

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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649: 30 Days of Traffic

During a recent 30 day period asteroid hunters spotted 88 small space rocks passing through our neighborhood.  Their diameters ranged from the length of a Uhaul Van to one that would occupy the majority of a city block.  NASA only classifies one of them, 2021 KT1, to be a Potentially Hazardous Asteroid. 2021 KT1 is 750 feet in diameter, can come to about 19 lunar distances from us, and is no threat to our home planet in the foreseeable future. Most of the close approaching asteroids which passed near us during this 30 day period, are tiny,  having an average diameter of only 30 feet.  2021 LX1 is the largest of the nine of them which came closer to our home planet than our Moon.  2021 LX1 was discovered the day after it passed less than half the Moon’s distance from us by the Atlas group in Hawaii and was subsequently tracked by telescopes in Tican , Italy, and Arizona.  2021 LX1 is approximately 43 feet in diameter which is slightly over half the size of the 66 foot diameter space rock that exploded over Chelyabinsk, Russia.  The Chelyabinsk meteor produced a fireball brighter than the Sun as well as an air blast that injured nearly 1,500 people and damaged 7,200 buildings in February of 2013.   According to the Purdue University and Imperial College of London’s impact calculator,  a space rock like 2021 LX1 enters the Earth’s atmosphere about once every 24 years, explodes at an altitude of 88,000 feet, produces a sonic boom that could shatter windows, and is likely to rain large fragments onto the Earth’s surface for meteorite hunters to discover.  

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

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