Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 603 & 604: Discovering Alien Life & Comet Rankin

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • Project Breakthrough Listen is spending 100 million dollars over a 10 year period to survey the 1 million nearest stars.
  • David Rankin discovered C/2020 K6 (Rankin) in Sagittarius.

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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603: Discovering Alien Life

Our star is only one among hundreds of billions in the Milky Way galaxy which itself is only one of a hundred billion or more galaxies in the known universe. How can it be that humans are the only creatures to look at the night sky and wonder about who else is out there?  To answer this question Project Breakthrough Listen is spending 100 million dollars over a 10 year period to survey the 1 million nearest stars in search of light or radio signals from other technological creatures. A fundamental hurdle for all those looking for extraterrestrial life and advanced civilizations may be prejudices like “extraterrestrial life metabolizes and is powered like we are on Earth” or  “alien intelligent beings understand their place in the Universe using the science and mathematics humans have invented” or that “artificial intelligence in our computers somehow is not biased with the human point of view”    

Undaunted by all this scientists are defining technosignatures like radio signals that don’t seem to be natural,  planets with air pollution, megastructures that block the light from a star which indicates the intelligent beings are harvesting of its energy, light pollution from city lights and more. To avoid missing clues that point to the existence of alien beings an MIT Graduate Student, Claire Webb  suggests that humans should take a hard look at our race to see what we might look like to another life form.  Instead of studying alien creatures she is studying us. Her research may prove to be very important in defining technosignatures of alien life which suggest that we are not alone.

604: Comet Rankin

My Catalina Sky Survey teammate David Rankin was asteroid hunting in the constellation of Sagittarius with our 60 inch telescope when he spotted a faint object moving through the night sky. Additional observations by telescopes in Arizona, New Zealand, Australia, and Italy verified that David’s fuzzy object is a previously unknown long period comet. Scientists at the Minor Planet center used these data to estimate the details its orbital path about the Sun and give it the name C/2020 K6 (Rankin). This rare visitor to our neighborhood travels on a path that takes it from between the orbits of Jupiter and Saturn out to 144 times Pluto’s distance from the Sun and back again once every 154,000 years or so.

Unfortunately it does not come close enough for us to see with the naked eye. There may be as many as a trillion small icy objects like David’s discovery in the Oort cloud near the outer edge of our solar system. Very rarely one of these frozen ice balls is jostled by the gravity of a nearby star causing its distant path about our Sun to be transformed into one which takes it near the planets we know. Most of these small comets pass unnoticed by humans although occasionally one can become bright enough to be seen with the naked eye.

The last time that Comet C/2020 K6 (Rankin) came near Earth our ancestors were likely to be wearing clothes, using stone tools, and hunting in Ethiopia. It is hard to imagine what life might be like on planet Earth 154,000 years from now and if there will any of our descendents to witness Comet C/2020 K6 (Rankin)’s return.

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

End of podcast:

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