Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps.  575 & 576: Big, Dangerous, Tough & Loneliest Asteroid

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • Teddy Pruyne discovered 1,200 foot diameter 2019 LZ1.
  • Brian Africano discovered 340 foot diameter 2019 EJ3.

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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575: Big, Dangerous, and Tough

Recently my Catalina Sky Survey teammate Teddy Pruyne, discovered a potentially dangerous and perhaps valuable asteroid with our 60 inch telescope on Mt. Lemmon, AZ as it streaked through the  constellation of Leo.  Further observations by telescopes in Arizona, California, and Tenerife allowed astronomers at the Minor Planet Center to calculate an orbit, give it the name 2019 LZ1, and estimate it to have a 1200 foot diameter.  On its current Sun approaching path, 2019 LZ1 crosses the orbits of Mercury, Venus, and Mars.  Further, this giant space rock  can come to less than the Moon’s distance from planet Earth.  Amazingly 2019 LZ1 travels so close to the Sun that it receives 6 times more solar energy than heats the surface of Mercury to 800F. This asteroid has made many such trips which suggests that it is made of tough rocky material.

According to the Purdue University and Imperial College of London’s impact calculator, a giant space rock like 2019 LZ1 enters the Earth’s atmosphere about once every 100,000 years and could create a 1700 foot deep crater 4.7 miles in diameter in sedimentary rock.  If 2019 LZ1 has the composition of a typical stony meteorite it is likely to have a mass of 94 million metric tons and thus contain significant amounts of iron, nickel, gold, and other precious metals, and water.  Though it is unlikely to ever strike the Earth, someday, 2019 LZ1 may become a valuable source of raw materials for space colonists.

576: Loneliest Asteroid

My Catalina Sky Survey teammate Brian Africano was observing , in the constellation of Leo,  with our Schmidt telescope on Mt. Bigelow, Arizona when he spotted a point of light moving at 40 miles/second. After Brian posted his observations on the Minor Planet Center’s Near Earth Object Confirmation Page this objects unusually high speed got asteroid hunters attention and it was tracked by telescopes in Arizona, Tenerife, Chile, England Hawaii, and Tican. These data allowed scientists to determine that this space rock has an orbit which takes it from near Earth out to beyond the planet Neptune and back again once every 120 years or so.  Astronomers gave it the name 2019 EJ3, estimated it to be about 340 feet in diameter, and determined that its path is tipped far from the path of the planets and most of the rest of the asteroids.  

2019 EJ3’s orbit is relatively uncertain since astronomers were able to track it for only 8 days, until it got too faint to observe, along its 120 year long path about the Sun.  In any event 2019 EJ3 spends most of its time high above the plane of the solar system far from our Sun.  Unknown asteroids on such a path worry asteroid hunters since one could appear from out of nowhere and be on a collision path with planet Earth.  Fortunately the odds that this will occur are vanishingly small.  The prospect of a suddenly appearing dangerous celestial visitor keeps my team the Catalina Sky Survey going to our telescopes in the Catalina Mountains north of Tucson, Az.

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

End of podcast:

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