Podcaster: Dr. Al Grauer
Title: Travelers in the Night Digest: Eps. Eps. 421 & 422: New Aten & Almost Dangerous
Organization: Travelers in The Night
Link : Travelers in the Night ; @Nmcanopus
Description: Today’s 2 topics:
- Carson Fuls and Greg Leonard discovered an Aten asteroid which orbits the Sun once every 272 days and on a path that crosses the orbits of Venus and Earth a number of times each year.
- At about 4 AM on Mt. Lemmon, Arizona, I was observing in the constellation of Cancer, when I came across a rapidly moving point of light in the predawn sky.
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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Transcript:
421 – New Aten
Recently my Catalina Sky Survey teammates Carson Fuls and Greg Lenoard discovered an Aten asteroid which orbits the Sun once every 272 days and on a path that crosses the orbits of Venus and Earth a number of times each year. Atens account for only about 6% of the Earth approaching asteroids that asteroid hunters discover. They are relatively dim and difficult to discover because they spend most of their time inside the Earth’s orbit with their sunlit side facing away from us. For example Carson and Greg’s newly discovered asteroid, 2017 WJ16, is bright enough for asteroid hunters to track for only about 50 nights every couple of years. It is about 150 feet in diameter and travels on an orbit which can bring it to a bit more than three times the Moon’s distance from Earth. When 2017 WJ16 is closer to the Sun than Earth it travels faster then we do allowing it to catch and just barely cross our orbit as we both travel about the Sun. In 2020, 2017 WJ16 will make one of it’s closer approaches to us when it comes to about less than 5 times the Moon’s distance from our home planet. At that time it will be traveling at 2.9 miles/second relative to us which is well within reach of our current rocket technology. I suspect that in the future if the pattern of colors which 2017 WJ16 reflects, reveals a high metal or water content humans will mine it to construct and operate their colonies in space.
422 – Almost Dangerous
At about 4 AM on Mt. Lemmon, Arizona I was observing, in the constellation of Cancer, with the Catalina Sky Survey’s 60 inch telescope when I came across a rapidly moving point of light in the predawn sky. After I reported my discovery observations on the Minor Planet Centers Near Earth Object Confirmation page, this previously unknown object was tracked by telescopes in Tenerife, New Mexico, Arizona, and Italy and given the name 2017 VV14. To be classified as Potentially Hazardous an asteroid must be greater than 448 feet in diameter and have an orbit which comes closer to ours than 5% of the Earth’s distance from the Sun. With an estimated diameter of 2,500 feet 2017 VV14 is large enough, however, it misses being classified as being potentially hazardous since it’s orbit misses coming close enough to ours by only 3,000 miles. When I first spotted 2017 VV14, it had crossed the orbit of Mars traveling at 7.7 mi/s and was on it’s way to a point three quarters of Jupiter’s distance from the Sun which it will reach in April of 2019. After that it will head back into the inner solar system. In 2020 this large space rock will pass closer to the Sun than the planet Mercury traveling at an amazing 43 miles per second. To survive such a harrowing close pass to the Sun 2017 VV14 must be made of metallic rocky material and could be of interest to asteroid miners.
For Travelers in the Night this is Dr. Al Grauer.
End of podcast:
365 Days of Astronomy
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