If the asteroid Apophis were to collide with Earth 30 years from now, it would strike with the force of 57,000 Hiroshima bombs. The aircraft-carrier-size rock could wipe out a city the size of Los Angeles and cause a 30-foot tsunami to smack into southern California. There's only a 1 in 5,500 chance of impact, but it's a chance that NASA is not willing to take.

So in late October, the space agency outlined a three-phase plan to observe, track, and deflect the rogue rock over the next two decades.

If ET is out there, chances are SETI (the Search for Extraterrestrial Intelligence) will hear him first-thanks in no small part to Steven Spielberg, the man behind 1982's smash ET: The Extra Terrestrial, who donated $100,000 to Carl Sagan's Planetary Society in 1985 to keep its receivers pointing heavenward. With Spielberg set to re-release the sci-fi classic on March 22, we thought we'd check in with Louis Friedman, head of the Planetary Society, to see how the search for the real ET is going.
Popular Science So have aliens dropped us a line yet?