Are We Alone in the Universe?

Feb. 8, 2008— -- Scientists today remain engaged in the age-old search for extraterrestrial life, hoping that modern technologies will help them detect and possibly communicate with whatever they find.

Just this week, NASA beamed the Beatles song "Across the Universe" into space. The radio signals will take more than 2 million years to reach our nearest galaxy, Andromedea.

"I don't think the human race has a future unless we go into space. We need to expand our horizons beyond planet Earth," says legendary astronomist and physicist Stephen Hawking.

But don't look to Hollywood's versions in such movies as "Alien" or "ET" to recognize extraterrestrial life, astrophysicist and author of "Death by Black Hole," Neil DeGrasse Tyson warns.

"They've got two legs, arms, fingers, maybe three fingers, not five. They have faces. We have other life forms on Earth with whom we have DNA in common that look less like humans than Hollywood aliens do!" he said.

Tyson, who serves as director of the Hayden Planetarium at the Rose Space Center in New York City, says there's more variety among our DNA cousins on Earth, e.g., a jellyfish, a horse, a yeast cell or an oak tree.

"I think the best alien ever, ever, ever, ever was the Blob. Didn't look like anything here on Earth, did it? It was creepy and scary. And it was clearly alive," Tyson said.

Scientists are listening every day for signals from another galaxy.

Recently, in Australia, they got excited picking up an odd radio pulse they couldn't explain, at frequencies the human ear can't hear.

"We don't know what this mysterious radio pulse is. I doubt that's extraterrestrial. I think it's more likely a natural phenomenon," explained Dan Werthimer, a physicist at the University of California at Berkeley.

Scientists have asked millions of amateur researchers around the world to get involved by downloading a program that allows personal computers to process data from the skies.

"Everybody gets a different part of the sky to analyze. … It shows you the most interesting signal that it's found so far," Werthimer said.