We are not alone. Ask the Earthlings around you if they agree and many will nod emphatically, certain that out there in the vast, dark, and generally undiscovered universe, life in some form or fashion exists. And since Galileo's telescope first scanned the skies, the search for signs of life beyond the Big Blue marble continues.
Right now, a swarm of probes and landers and rovers are all heading for the Red Planet. And although news reports continue to say the UK-built Beagle 2 has still not phoned home, NASA hopes that its own robot, called Spirit, will soon land safely and summarily call Earth, with news of its neighbor, and a fix for a bad case of interplanetary loneliness.
Executive Editor of Sky and Telescope Magazine, and Editor of a new magazine called Night Sky
David Grinspoon, astrobiologist., principal scientist at the Southwest Research Institute in Boulder, Colorado, and author of the new book, "Lonely Planets: The Natural Philosophy of Alien Life."
Steve Squyres, principal investigator for the Mars Exploration Rover Project, and professor of Astronomy at Cornell University.
