Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 235E & 236E: Potential Mining Target & Incoming

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s two stroy:

  • The Catalina Sky Survey team members Greg Leonard & Richard Kowalski discovered 2016 GC221, a prime target for asteroid mining, though it is traveling a bit faster than we’d prefer.
  • Catalina Sky Survey team member Greg Leonard discovered 2016 CG18 which was used recently as a test object for rapid response observing protocols. 2008 TC3, by the way, WAS on such a collision course with Earth, but exploded harmlessly over the Nubian desert on October 7th, 2008.

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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235E – Potential Mining Target
Mining asteroids may be a much cheaper way to get the raw materials that space colonists need when compared to the cost of lugging supplies up from the surface of our planet. Using the abundant solar energy in space, water ice from asteroids can be turned into hydrogen and oxygen which is ideal rocket fuel. The metals which many asteroids contain can be turned into the items space explorers need.

Recently my Catalina Sky Survey teammates Greg Leonard and Richard Kowalski found an asteroid which has an orbital period about the Sun of 382 days. The new space rock was tracked by eleven observatories around the world. These data allowed scientists at the Minor Planet Center to calculate its orbit, estimate its size, and give it the name 2016 GC221.

Greg and Richard’s new space rock, 2016 GC221, is about 125 feet in diameter. In the next 50 years this small space rock will make ten approaches to planet Earth.

It will be interesting to obtain a spectrum of 2016 GC221 so that we will know what it is made of. It’s minimum velocity relative to the Earth is about 5.9 miles per second. This about 50% faster than we would like since it will take more rocket fuel to rendezvous with it than it would for some of the other asteroids we have found. If 2016 GC221 happens to contain metals like platinum, nickel, iron, and copper or substantial amounts of water ice I suspect that humans will find a way to get there.

236E – Incoming
Suppose asteroid hunters detect a tiny moving point of light in the night sky which appears to be on a collision course with planet Earth. The questions which immediately come to mind are what is this object like? When and where might it impact the surface of our world? In order to answer these we need data.

To get some practice at responding to an incoming asteroid, researchers trained four telescopes in Hawaii and New Mexico on an object, now called 2016 CG18, which my Catalina Sky Survey teammate Greg Leonard had just found streaking through the night sky.

Because Greg was able to discover this small asteroid before it made its closest approach to us, astronomers at Apache Point Observatory, NASA’s Infrared Telescope Facility, Gemini North, and Magdalena Ridge Observatory were able to track and obtain data on 2016 CG18 as it passed between the Earth and our Moon.

Dr. Nicholas Moskovitz of Lowell Observatory headed up the team that analyzed the data from this coordinated effort. What this team found is that 2016 CG18 is only about 21 feet in diameter and spins extremely slowly taking about 2 hours to complete one of its complex tumbling motions.

This coordinated research effort has tested rapid response observing protocols which can be used on a difficult fast moving object, like 2008 TC3, which is on a collision course with planet Earth.

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

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