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.

Dealing with Negativity

First hour guest, Dr. Judith Orloff spoke about dealing with stressful economic times. We live in a world permeated with fear and negativity and that gets absorbed into our bodies, she said. We should turn our attention away from this vortex of negativity, and bring in positive thoughts by being in the moment, she suggested.