Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 185E & 186E: Rick’s 2 Homers & Asteroid Water Wagons

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s two stroy:

  • Rik Hill knocked two out of the park! By discovering PHAs 2015 TD323 and 2015 TK238.
  • Asteroids have been hauling water to our Moon and depositing it in places which are very handy for future human colonists.

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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185E: Rick’s 2 Homers

During his last official observing run before retiring, my Catalina Sky Survey teammate, Rik Hill knocked two out of the park. On successive nights he discovered two new potentially hazardous asteroids 2015 TD323 and 2015 TK238. Not to worry, neither of these asteroids are a threat to Earth in the foreseeable future. However, they are large enough and can come close enough to prompt asteroid hunters to keep careful track of them.

Both of Rik’s discoveries are called Apollo Earth approaching asteroids since their orbit crosses Earth’s path around the Sun like the asteroid Apollo. After Rik discovered 2015 TD323 streaking across the night sky at 17 miles per second, it was tracked by telescopes in Japan, New Zealand, Chile, France, and New Mexico.  2015 TD323 has a diameter approximately the height of the Eiffel tower. Our equipment is so sensitive that Rik was able to discover it at a distance of 1.5 million miles from Earth. This asteroid makes a trip around the Sun in a bit over 2 years on a path that takes from between Mercury and Venus out to past Mars before it heads in our direction again.   It will not come close to Earth again until 2155. 

Rik will be missed on our team. During the past three years he discovered 377 Earth approaching objects including 18 potentially hazardous asteroids.  With 27 comet’s to his credit, Rik is in third place on the list of comet discoverers.

186E: Asteroid Water Wagons

Our Moon is the nearest and most likely place for humans to colonize in the near future. It has a hostile environment where air and liquid water as we know them on Earth are not to be found.

For humans water is required for drinking and growing plants. By using the abundant solar energy on the Moon, water can be separated into oxygen and hydrogen giving people air to breathe and hydrogen to fuel rockets to Mars and other destinations. 

There are ice deposits near the polar regions on the moon, however, at these locations the available solar energy is limited, the temperatures are very cold, and radio communication with Earth is difficult.

In the past astronomers hypothesized that comets are the source of water on the Earth and Moon. However, calculations by Svetsov and Shuvalov published in Planetary and Space Science indicate that when a comet impacts the Moon it is likely that 99% of its water evaporates into space and is lost. On the other hand their work indicates that asteroids have been hauling water to our Moon and depositing it in places which are very handy for future human colonists.  Specifically it appears probable that 2 to 4.5 % of lunar craters are likely to contain substantial amounts of water in the form of hydrated minerals. These asteroid impact craters are a convenient source of water and solar energy for lunar bases and are likely to be the home of human lunar colonists.

For Travelers in the Night this is Dr. Al Grauer

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