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Sorry everyone, the date is 21 Oct 2008 http://www.youtube.com/view_play_list?p=0E6B958B03F6DE39 Astronomer and author Phil Plait discussed his new book Death from the Skies!, which outlines various ways the human race could die from astronomical events. An asteroid or comet impact could wreak havoc on the planet. For instance, a one-mile-long object that hit the ocean could create a 1000 ft. high tsunami, moving at 500 mph. It could literally scour clean the coastlines, killing millions, he detailed. The B612 Foundation is working on ways to prevent asteroid impacts, such as by sending out probes that could alter asteroids' orbits, he reported. Another dire situation he pondered involved the death of the universe. While theoretical, and billions of years in our future, the continued expansion of the universe could lead to The Big Rip in which matter is torn apart. More likely, our galaxy would just move further and further away from other galaxies until we could no longer see them, he said. Gamma Rays, a kind of cosmic blowtorch sent out by a certain type of super nova could potentially obliterate life, but Plait happily noted it didn't appear any candidate stars were currently close enough to Earth to zap us. He also touched on a number of other potentially catastrophic but non-imminent consequences, such as a black hole eating our planet, damaging solar flares, an alien attack, and the collision of the Milky Way galaxy with neighboring Andromeda. Such a collision, which is due in about two billion years, could cause some stars to be flung far out into the galaxy.

To find out more visit: http://www.nasa.gov/mission_pages/GLAST/news/first_year.html Want more? Subscribe to NASA on iTunes! http://phobos.apple.com/WebObjects/MZStore.woa/wa/viewPodcast?id=283424434 Or get tweeted by NASA: http://twitter.com/NASAGoddard In its first year of operations, NASA s Fermi Gamma-ray Space Telescope has mapped the entire sky with unprecedented resolution and sensitivity in gamma-rays, the highest-energy form of light. On May 10, 2009 a pair of gamma-ray photons reached Fermi only 900 milliseconds apart after traveling for 7 billion years. Fermi s measurement gives us rare experimental evidence that space-time is smooth as Einstein predicted, and has shut the door on several approaches to gravity where space-time is foamy enough to interfere strongly with light.