Podcaster: Dr. Al Grauer
Travelers in the Night Digest: Eps. 275 & 276: No Place Like Home & Big 3

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • Earth is so far unique in the cosmos. The human use of fossil fuels is changing the climate which will make our lives difficult in ways we are just learning to appreciate.
  • Carson Fuls of the Catalina Sky Survey discovered 3 PHAs, Potentially Hazardous Asteroids, during one momentous 6 night observing run.

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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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275 – No Place Like Home
Robotic spacecraft from Earth have been traveling around the solar system for decades. What they have found is that there may be a few places on which the toughest terrestrial life forms could exist but nowhere that you could survive without a space suit. A striking by product of these missions are the photographs of our home planet that these robots have sent back to Earth.

Astronomers are finding thousands of planets orbiting distant stars, however, our home, the Earth, is so far unique in the cosmos. It is situated in the middle of the habitable zone around our Sun where temperatures suitable for life as we know it exist. Not all planets are so fortunate. Recently published research indicates that if the Earth were near the outer edge of our Sun’s habitable zone the climate would feature prolonged ice ages with a few warm periods in-between during which complex life could flourish. If the Earth were closer to the Sun it would likely to be too hot for life on most of it surface.

On Earth the human use of fossil fuel is changing the climate which will make our lives difficult in ways we are just learning to appreciate. Prepare yourself for more violent storms with extremely dry periods in between. You may arrive at your favorite beach to find it under water. Pesticide use threatens the bee population without which agriculture’s ability to feed us comes into serious question. Clean air, water, and healthy food to eat can not to be taken for granted.

Wake up. Humans can not trash this planet and plan to move on. There is no other place like home.

276 – Big 3
During a 6 night observing run with the 60 inch telescope on Mt. Lemmon, Arizona, my Catalina Sky Survey teammate Carson Fuls discovered three new Potentially Hazardous Asteroids. They range in size from 600 to 1500 feet in diameter. Fortunately, none of them comes closer than about 14 times the Moon’s distance from us.

A recent study by Dr. Pasquale Tricarico of the Planetary Science Institute in Tucson, Arizona estimates that asteroid hunters have discovered approximately one third of the large potentially dangerous asteroids which are likely to exist. His study also predicts that there are approximately 400,000 Earth approaching objects larger than an SUV. A small object like one of these enters our atmosphere every few years, disintegrates at about 3 times the height that airliners fly, and sometimes produce meteorites that we can find on the ground. Very rarely one of them explodes over a populated area as was the case in Chelyabinsk, Russia in 2013 where nearly 1,500 people were injured by flying glass and other debris. Soon asteroid hunters hope to be able to find small Chelyabinsk sized impactors before they enter our atmosphere so as to be able to warn people in the affected area to stay away from doors and windows. Humans still have a lot to learn. For example if celestial visitors are darker and thus reflect less sunlight than what we currently suspect shorter warning times for asteroids of various sizes will be the results.

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

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