NASA finds new life form

It may be a game-changer in the search for alien life.

NASA scientists unveiled a discovery Thursday that it says redefines life as we know it-- the existance of a type of bacteria that thrives on the toxic chemical arsenic.

NASA scientist Felisa Wolfe-Simon.

(SOUNDBITE) (English) FELISA WOLFE-SIMON, NASA ASTROBIOLOGY RESEARCH FELLOW, SAYING:

"And if there's an organism on Earth doing something different, we've cracked open the door to what's possible for life elsewhere in the universe, and that's profound, and to understand how life is formed, and where life is going. This microbe substitutes arsenic for phosphorous in its basic bio-molecules. And what else might we find? What else might we want to look for?"

The finding in a salty lake near Yosemite National Park in Californaia shows just how little scientists know about the variety of life forms on Earth, and may greatly expand where they should be looking for life on other planets and moons.

(Reuters)