Today (Thursday), at 11:00 AM Pacific time, a team of NASA scientists appears poised to announce a discovery of arsenic based life at Mono Lake in California. The implications of this discovery are enormous. It means that NASA might begin an intensive search for arsenic-based life on other planets as well. Here’s a video from Dutch television that highlights the work of one of the scientists listed as participating in today’s press conference, Felisa Wolfe-Simon:

Here’s some additional information from Robert Quigley at Geeko System:

One of the four participants in NASA’s press conference tomorrow is NASA astrobiology research fellow Felisa Wolfe-Simon, who has spent two years researching Yosemite Park’s Mono Lake, which has one of the highest natural concentrations of arsenic of any site in the world. Skymania spoke to astrobiologist Lewis Dartnell, who said, “I’m 90 per cent certain that Felisa has found something in Mona Lake and they have been able to demonstrate in some way that it uses arsenic in its metabolism rather than be poisoned by it.” You may recall from your high school biology class that ATP, or adenosine triphosphate, is the so-called “energy currency” of the cell, and powers many key metabolic functions; key to ATP’s structure is the element phosphorus. Arsenic sits directly below phosphorus on the periodic table of elements and can do many of the same things chemically, but it’s usually poisonous to living things. Arsenic-powered organisms, then, would indeed represent different forms of life from those which we’re most familiar, both because they’d have ATP-like molecules with arsenic swapped in in phosphorus’ place and because they had evolved mechanisms such that arsenic didn’t kill them. NASA Watch’s Keith Cowing writes that “[r]eliable sources within the Astrobiology community tell me that the announcement does indeed concern Arsenic-based biochemistry and the implications for the origin of life on Earth, how it may have happened more than once on our planet, and the implications for life arising elsewhere in the universe.”

And here’s part of the NASA press release:

WASHINGTON — NASA will hold a news conference at 2 p.m. EST on Thursday, Dec. 2, to discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life. Astrobiology is the study of the origin, evolution, distribution and future of life in the universe. The news conference will be held at the NASA Headquarters auditorium at 300 E St. SW, in Washington. It will be broadcast live on NASA Television and streamed on the agency’s website at http://www.nasa.gov. Participants are:

– Mary Voytek, director, Astrobiology Program, NASA Headquarters, Washington

– Felisa Wolfe-Simon, NASA astrobiology research fellow, U.S. Geological Survey, Menlo Park, Calif.

– Pamela Conrad, astrobiologist, NASA’s Goddard Space Flight Center, Greenbelt, Md.

– Steven Benner, distinguished fellow, Foundation for Applied Molecular Evolution, Gainesville, Fla.

– James Elser, professor, Arizona State University, Tempe

You might want to stop what you’re doing tomorrow (if you can) and check out the press conference at its scheduled time. Here’s the live stream address again: http://www.nasa.gov.

And a nice secondary benefit of the discovery of an arsenic-based life form (if that is what the announcement proves to be) is that it will help promote Mono Lake’s preservation.