73 réponses à ce sujet

[Mallissin]

Yep, nothing extraterrestrial about it. They just found a type of bacteria that uses arsentic as a DNA binder.

http://www.bbc.co.uk...onment-11886943
http://arstechnica.c...nd-proteins.ars


NASA has let me down yet again.

Modifié par Mallissin, 02 décembre 2010 - 06:12 .

[Sigma Tauri]

Kimosabe0 wrote...

Ah ok, thank you for that explanation, I don't have much knowledge of physics and chemistry

And ofcourse we can't be absolutely sure about that, it would be impossible to check if that is true everywhere in the universe

The fact that water is connected to life narrows astrobiologists' search for it. If there's likely water in a world, there's likely to be life. That's why they're interested in drilling under Europa because they think there might be an ocean. It's a complete unknown if water is necessary for life, so astrobiologists look for the one fact they can prove.

[Kaiser Arian XVII]

I've found life in my backyard!

[Sigma Tauri]

Mallissin wrote...

Yep, nothing extraterrestrial about it. They just found a type of bacteria that uses arsentic as a DNA binder.

http://arstechnica.c...nd-proteins.ars

NASA has let me down yet again.

If arsenic can be incorporated into something as fundamental to life as DNA, the possibility of a silicon-based life form or a turian or quarian is not out of the question. Eh, it's an evolutionary biochemist's wet dream.

Modifié par monkeycamoran, 02 décembre 2010 - 06:15 .

[Fiery Phoenix]

If anyone is interested, the live stream of the conference can be seen here:



http://www.nasa.gov/...satv/index.html

[Fiery Phoenix]

monkeycamoran wrote...

The fact that water is connected to life narrows astrobiologists' search for it. If there's likely water in a world, there's likely to be life. That's why they're interested in drilling under Europa because they think there might be an ocean. It's a complete unknown if water is necessary for life, so astrobiologists look for the one fact they can prove.

In theory, all that is needed for life is three things:
1) Organic components; that is, molecules with both carbon and hydrogen.
2) A sufficient energy source (e.g. the Sun).
3) Water; preferably in its liquid state.

It's theoretically believed that with these three requirements satisfied, simple lifeforms should be around.

Modifié par FieryPhoenix7, 02 décembre 2010 - 07:00 .

[Swordfishtrombone]

Watching it now. (Thanks for the link!)



It's very interresting - it demonstrates one possible variant, at the most fundamental level, of life's basic molecules. To have arsenic substituting for phosphorus is the biggest deviation from the basic DNA/RNA structure that I've heard of. That is, IF this discovery pans out.



Still, it doesn't answer the basic question of whether the RNA and DNA structures are the only, or the most likely structures upon which life is based in the universe. For that, we'd really need to discover some simple living things that originate outside Earth.

[Fiery Phoenix]

Yeah, I'm watching it right now as well. It's not what I was expecting, but still interesting nonetheless.

[Mister Mida]

You know, when I first heard about this discovery, the first thing I thought was: 'Didn't we know this stuff already? That live can be made out of different elements other than we know already?' Not so long ago I watched some documentaries wherein Stephen Hawking discussed the existence of alien life and he too made this same assessment. And this was broadcasted months ago. So did Hawking and this biologist work together or did he just figured it out earlier?

[Khayness]

Well, we knew this in theory, but now we have proof.

[Fiery Phoenix]

Yup, that's right, Khayness.

[Fiery Phoenix]

LOL! USA Today's question is so blunt.

[Stanley Woo]

this is pretty awesome. not as awesome as finding potential life on Rhea or Titan, but increasing our search parameters is pretty significant.

[Mallissin]

B1NARY C0DE wrote...

Yeah, that is the official story, but only an idiot believes the official story.

Are you saying that aliens mated in California's hot springs during a clandestine vacation here on Earth, leaving behind a sexually transmitted retrovirus from their world that altered the bacteria in the pool to using arsenic as a DNA binder?

That's crazy talk! How could you suggest such a thing!?

[Fiery Phoenix]

AwesomeName wrote...

FieryPhoenix7 wrote...

LOL! USA Today's question is so blunt.

What did they ask?

Well, it wasn't a question per se. They basically expressed their disappointment and said they were expecting "more". It was awkward; I could see it in everyone's face in the video.

[Tentura]

B1NARY C0DE wrote...
Yeah, that is the official story, but only an idiot believes the official story.

That's enough!  You're soldiers - act like it.    I see what you did there.

Modifié par Tentura, 03 décembre 2010 - 06:35 .

[Swordfishtrombone]

AwesomeName wrote...

FieryPhoenix7 wrote...

AwesomeName wrote...

FieryPhoenix7 wrote...

LOL! USA Today's question is so blunt.

What did they ask?

Well, it wasn't a question per se. They basically expressed their disappointment and said they were expecting "more". It was awkward; I could see it in everyone's face in the video.

Man, science journalists usually suck at understanding what they're reporting anyway.

The problem is that most news organizations don't have dedicated science journalists anymore - they give the science gigs to someone usually reporting on the latest exploits of Lindsey Lohan.

The journalist doing the science bit usually doesn't have any science background whatsoever, and is likely to be no more educated on any relevant subject than your average joe off the street. It's a sad state science journalism is in.

[grregg]

The conference should have looked like this: xkcd.

Modifié par grregg, 03 décembre 2010 - 06:53 .

[Mallissin]

grregg wrote...

The conference should have looked like this: xkcd.

Hmmm...arsenic martinis...yummy.

[Swordfishtrombone]

grregg wrote...

The conference should have looked like this: xkcd.

Gotta love xkcd!