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All the buzz is that NASA has found out something important.
http://www.nasa.gov/home/hqnews/2010/nov/HQ_M10-167_Astrobiology.html
http://www.nasa.gov/home/hqnews/2010/nov/HQ_M10-167_Astrobiology.html
The tools and experiments researchers use to look for new forms of life - such as those on missions to Mars - would not detect biochemistries different from our own, making it easy for scientists to miss alien life, even if was under their noses.
"When you don't know what you're looking for or what it'll look like, you have to come up with a whole scientific method for how to go about [looking for] it," added Steven Benner, a Fellow at the Foundation for Applied Molecular Evolution and The Westheimer Institute for Science and Technology in Gainesville, Florida.
Scientists are looking in places where life isn't expected - for example, in areas of extreme heat, cold, salt, radiation, dryness, or contaminated streams and rivers. Davies is particularly interested in places that are heavily contaminated with arsenic, which, he suggests, might support forms of life that use arsenic the way life as we know it uses phosphorus.
[PLAIN said:http://www.nasa.gov/home/hqnews/2010/nov/HQ_M10-167_Astrobiology.html]...to[/PLAIN] 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.
Ygggdrasil said:It seems that researchers may have discovered life on Earth that uses novel biochemistries based on arsenic (certainly a discovery worth publication in Science).
Mu naught said:I hate the way people/the media hype everything up. We're living in the age of exaggeration.
Redbelly98 said:3. Finding life.
4. Finding intelligent life.
I'm guessing this would have to be at level 1 or 2. We'll see tomorrow.
hamster143 said:There's also level 0 - speculating about conditions that could be compatible with supporting life.
FlexGunship said:I think your conclusion might be premature. I read that to mean that someone has thought of a way that this could be possible. Not that there are actually candidates for life that works this way.
hamster143 said:There's also level 0 - speculating about conditions that could be compatible with supporting life. Since none of the participants of the conference strike me as the kind that would be able to find anything physical (they are all theorists), we should be closer to level 0 than to level 2.
http://www.timesonline.co.uk/tol/news/science/eureka/article7040864.eceCould the Mono Lake arsenic prove there is a shadow biosphere?
Do alien life forms exist in a Californian lake? Could there be a shadow biosphere? One scientist is trying to find out.
Mono Lake has a bizarre, extraterrestrial beauty. Just east of Yosemite National Park in California, the ancient lake covers about 65 square miles. Above its surface rise the twisted shapes of tufa, formed when freshwater springs bubble up through the alkaline waters.
Felisa Wolfe-Simon, a geobiologist, is interested in the lake not for its scenery but because it may be harbouring alien life forms, or “weird life”. Mono Lake, a basin with no outlet, has built up over many millennia one of the highest natural concentrations of arsenic on Earth. Dr Wolfe-Simon is investigating whether, in the mud around the lake or in the water, there exist microbes whose biological make-up is so fundamentally different from that of any known life on Earth that it may provide proof of a shadow biosphere, a second genesis for life on this planet...
Simon is investigating whether, in the mud around the lake or in the water, there exist microbes whose biological make-up is so fundamentally different from that of any known life on Earth that it may provide proof of a shadow biosphere, a second genesis for life on this planet...
It has been speculated that the earliest life on Earth may have used arsenic in place of phosphorus in the backbone of its DNA
DaveC426913 said:Question about this arsenic thing. It's a substitute for phosphorus, right? But it's not a substitute for COHN-, or even RNA/DNA-based life, right?
This hypothetical arsenic-based life is still organic and based on RNA?
Ygggdrasil said:I would be absolutely stunned if Thursday's Science paper announced they found As-DNA or As-RNA. I could definitely see other aspects of arsenic metabolism (e.g. using it as an electron donor for the fixation of carbon dioxide) and maybe limited incorporation into some biosynthetic pathways, but an organisms with a form of genetic material chemically distinct from all other known organisms would be a huge discovery.
chemisttree said:All the buzz is that NASA has found out something important.
http://www.nasa.gov/home/hqnews/2010/nov/HQ_M10-167_Astrobiology.html
DaveC426913 said:Wow. I went to that page and the video completely froze my system - even the mouse (yet the audio played on). I had to do a hard boot recovery.
Jack21222 said:Are you stunned?
It still uses some phosphorus, so it hasn't swapped ALL of it out for arsenic, but still, it's pretty freaking cool.
Redbelly98 said:I am puzzled as to why NASA has any role in this. It is terrestrial biology.
CNN said:Washington (CNN) -- Scientists have discovered a form of bacteria that can thrive on arsenic -- an element generally considered toxic -- dramatically expanding both traditional notions of how life is sustained and the range of where it might be found in the universe, NASA funded-researchers said Thursday.
The bacterium -- strain GFAJ-1 of the Halomonadaceae family of Gammaproteobacteria -- was scooped from sediment in California's Mono Lake, an area rife with high levels of naturally occurring arsenic, it said.
Scientists were able to grow the microbes from the lake with only small portions of phosphorous -- considered an essential nutrient in the biomolecules of naturally occurring bacteria.
The bacterium not only grew but also incorporated the arsenic molecules into its DNA (As-DNA), in place of phosphorus, she said.
Orion1 said:According to my understand of molecular biology, an organism based upon As-DNA ... represents a new class of life that is relatively distinct from P-DNA.
Orion1 said:According to my understand of molecular biology, an organism based upon As-DNA - if that is the proper scientific nomenclature for such a molecule, represents a new class of life that is relatively distinct from P-DNA. Similarly, a new class of life would also be represented by Si-DNA or Silicon based life where Silicon is replaced by Carbon, however such a class of life would have to respire Silicon Dioxide instead of Carbon Dioxide, and because Silicon Dioxide is not a gas, such a class of life is highly improbable.
With further genetic engineering of this bacterium away from P-DNA evolution, it may be possible for the organism to completely substitute Arsenic as As-DNA.
Applications for such a bacterium could involve removing Arsenic from contaminated soils and water.
Is the probability of class As-Si-DNA based life in the Universe non-zero?
Student1983 said:Can we really jump the gun to silicon based life? I mean, if the evidence is empirical, then we have an organism using "mostly" arsenic instead of it's usual diet. I would like to point out that these organisms are not totally weaned off of P-DNA. They just supposedly use arsenic in its place. I'm just curious if we have enough evidence to jump from arsenice to silicon here.
Okay, sounds reasonable.FlexGunship said:They funded the research under a branch of exobiology. Basically trying to answer the question: "what else should we look for that might indicate life?"