It's Life, Jim, But Not As We Know It

Space geeks have been crapping their pants since news hit the Interwebs Monday that NASA was holding a press conference "to discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life." The announcement further defined astrobiology as "the study of the origin, evolution, distribution and future of life in the universe."

"Aliens!" cried everyone from Fox News to Gawker. Cryptic at best, the spare press notice set the nerdsphere hamster wheel aspinnin' with unsubstantiated rumors that alien life had in fact, been discovered. In the methane lakes on Saturn's moon Titan, maybe, or the extraterrestrial microbes in the near Martian waters of Mono Lake. "Aliens!"

But NASA has fooled us before. Would it be like the blackhole debacle of two weeks ago? ("We found a new black hole in our cosmic back yard! It's an infant! It was born in 1979, if it were a person on Earth it would still remember when Johnny Carson was on TV!" -- except it wasn't born in 1979, that was just the first time it was visible from our vantage point. In actuality, the blackhole is 50 million light years away, which makes it 50,000,030 years old. NASA, your PR team sucks donkey balls.)

But yesterday's news proved to be a bit more exciting.

A team of researchers has found a microbe that can survive without phosphorus in its DNA make-up. Instead, the little dudes rely on highly toxic arsenic, which makes the microbes the only living thing on Earth that doesn't use phosphorus - previously believed to be one of the six essential building blocks of life, along with carbon, hydrogen, nitrogen, oxygen and sulfur.

Replacing phosphorus with arsenic in DNA, from yesterday's NASA press conference.

The microbes were culled from the bottom of Mono Lake in California, the highly toxic lake that formed 760,000 years ago, making it one of the oldest and freakiest lakes in North America. Mono Lake is prized for its bizarre ecosystem: There are no fish, but there are trillions of brine shrimp, alkali flies and single-celled algae. Its hypersaline waters are toxic and arsenic rich.

The press conference was timed with the release of an article in Science, authored by members of the research team who found the microbes and grew them in a lab. "It is building itself out of arsenic," geo-microbiologist Felisa Wolfe-Simon said at the press conference yesterday. Wolfe-Simon, a fellow at NASA's Astrobiology Institute and the U.S. Geological Survey, spearheaded the research and authored the Science paper with a laundry list of co-authors. "All life we know is the same biochemically, and this is a little different. It is suggesting there is another way to be alive."

These microbes don't rely on ATP either, which most high schoolers can tell you is essential for cell division and many other mandatory processes in any given cell. Basically, no life form we've been aware of on this pale blue dot has been without ATP or phosphorus, until now.

So why is this even relevant? Because it proves that planets don't need water and and carbon to sustain life. This is an expansion of the definition of life -- and that means textbooks will need to be rewritten, and these findings may have an impact on bioenergy research, as well as toxic waste management, two areas discussed at the press conference.

"It's not about arsenic, it's not about Mono Lake, its about thinking about life in a planetary context. We've cracked open the door to what's possible for life elsewhere in the universe, and finding that what we think are fixed constants of life are not," Dr. Wolfe-Simon said.

Coupled with yesterday's announcement that the possibility of finding extraterrestrial life is now three times higher than previously expected--they've discovered eight elliptical galaxies, containing a shocking number of red dwarf stars, around which trillions of Earths could be orbiting--well, it's been a week that would have made Carl Sagan very, very proud.
(They're out there.)