Dr. Al Grauer hosts. Dr. Albert D. Grauer ( @Nmcanopus ) is an observational asteroid hunting astronomer. Dr. Grauer retired from the University of Arkansas at Little Rock in 2006. travelersinthenight.org Today's 2 topics: - Most asteroids that we observe have been baked by the Sun for billions of years. As a result, any ices or frozen gases that they may have once possessed are long gone. Comets on the other hand have spent so much time far from the Sun that they still contain volatile materials. As a typical comet approaches the Sun, the frozen gases and ices it contains evaporate to form a beautiful coma and a long tail. - Recently Dr. Adam Frank of the University of Rochester and Dr. Woodruff Sullivan of the University of Washington published a paper in which they addressed the question "What are the odds that humans are the only technological species that has ever arisen in a given volume of space"? Humans continue to look into the night sky and wonder what is out there. The immense distances and the uncertain lifetime of an advanced civilization make it seem unlikely that we will discover intelligent beings outside of Earth. However, I remain hopeful of one day waking to the news that we have received signals from thinking beings which live elsewhere in the Milky Way.   We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs.  Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too!  Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations.  Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org.