Scientific American: Did Life Come from Another World?

[bananas]

Long article in November issue of Scientific American magazine,
also online for free.

http://www.sciam.com/article.cfm?chanID=sa007&articleID=00073A97-5745-1359-94FF83414B7F0000

Did Life Come from Another World?
New research indicates that microorganisms could have survived a journey from Mars to Earth

[madeline_con]

1. microorganisms

They probably could blow in, buried on a meteor or something.

It will be twisted by next week to say life came to earth on alien spacecraft.

[ThoughtCriminal]

2. We are the Martians?

Or perhaps we have a common microbial ancestor.

[SnoopDog]

3. Considering, in the beginning...

the Earth was a coalescing molten sphere of fire... One could only deduce that life had to come at a later date - most likely from a meteor or asteroid.

Makes sense to me...

Hello Univerise... We are not quite ready for prime-time universal acceptance... Not yet... Maybe someday when intelligent life is predominate.

[frogmarch]

4. Well, yeah,

I suppose living cells could have come here from wherever, but the argument merely moves the question of how life began to another planet.

[bananas]

7. drat - the panspermia.org site is down

looks like a dns problem.

[moggie]

9. Or a dna problem n/t

[greyl]

23. Hold on there.

Why do you think it's most likely that life on earth originated from a meteorite or asteroid?

"... ... One could only deduce that life had to come at a later date - most likely from a meteor or asteroid."

That would assume that life can not possibly exist in conditions that our early earth had. That at first seems reasonable, but on the other hand, isn't a signature of life that it finds ways to 'circumvent' restrictions on its freedom? Just on earth we have examples of life thriving in scalding hot and below freezing temperatures. In any case, it would be a mistake to apply the boundaries of life we witness on earth, to life elswhere.
Iow, is it logically sound to assume that the living systems on earth are the 'best' and most adapted in the entire universe?

ed:form

[WindRavenX]

5. nucleic acids have been detected in deep space clouds and on meteors..

...so yeah, I'd say it's possible.

[TechBear_Seattle]

6. I subscribe, so I've read the article

I am rather put off at the apparent assumption that live arose on Mars first and was subsequently carried to Earth, seeding life here. Why couldn't it have been the other way around?

[Viking12]

8. Gravity?

Just a guess but: Earth orbits between Mars and the Sun. It would seem to be unlikely for cosmic debris to move away from the Sun.

[trotsky]

10. Maybe, too,

that Mars cooled sooner and had conditions more hospitable to life earlier.

[htuttle]

14. Not only that

But the latest theory on the origin of the moon says that we are actually living on Earth '2.0'. The original planet was struck by a very large body, and the resulting explosion created both our current Earth and the Moon. So we would have 'lost' a billion years or so there, too.

However, I don't think there's any more reason right now to believe that life came from Mars than that it came from random proteins floating through deep space. Or that life evolved first on Earth, for that matter. But it's interesting that it COULD have come from space.

[bananas]

11. Mars cooled first

so life could have developed there while Earth was still too hot.
But if you follow that line of thought, maybe life started on Pluto?
We are all Plutonians.

[TechBear_Seattle]

15. Concedo

I had forgotten about the "Lucifer Event", I think it is called, that is the likeliest scenario for the formation of our moon. That certainly would have nipped in the bud the first nascent life on this planet. Still, I see no reason to discount the likelihood that terrestrial life most likely evolved on its own, possibly with help from non-terrestrial life. Who is to say that the first earth life didn't "splash" to Mars when the moon formed, or that terran life wasn't reseeded by the return, centuries latter, of organic material was lost in that collision?

Dang it all, if Earth can't be the center of the solary system, much less the center of the universe, can't I at least argue that it is the center of life for our local bit of space?

[htuttle]

19. It's also possible that the original catalyst for life on Earth...

...was not something we currently consider 'alive', such as various organic molecules. Nucleic acids have already been detected in space. Perhaps given an appropriate environment, they start organizing to become 'alive' (cf., 'Miller's experiment').

Here's some more grist on this possibility:
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/A/AbioticSynthesis.html
http://neo.jpl.nasa.gov/news/news044.html

From the NASA link:

1998 KY26's color and radar reflectivity showed similarities to carbonaceous chondrites, primordial meteorites which formed during the origin of the solar system, and unlike any rocks formed on Earth. They contain complex organic compounds as well as 10 percent to 20 percent water. Some carbonaceous chondrites contain amino acids and nucleic acids, which are the building blocks of proteins and DNA, and hence, are of interest to scientists trying to unravel the origins of life.

But instead of putting Earth in the center of the origin of life, this would really say that life is something the universe just 'does', and would likely be common in one form or another (though radio communications do not seem to be common at this point, so "intelligent life" or more accurately, 'technological life' would still appear to be uncommon).

[greyl]

22. :) I feel your pain.

""Dang it all, if Earth can't be the center of the solary system, much less the center of the universe, can't I at least argue that it is the center of life for our local bit of space?""

Sure, as long as you are arguing with certain definitions of "center of life" and "local space". :) You'd win easily.

I mean, we are here now. On earth. Life as we know it and the humanity that we are participating in are obviously inseparable from earth, (or earth-like conditions).

It would be 'insane' to not be consciously centered around your life on earth, wouldn't it?

As opposed to "other worlds" or "after lives", I mean. :)

[greyl]

12. I've liked that hypothesis for a while.

Too bad siglines are off as I'm writing this. ;)

[Angry Girl]

13. So what happened? Because you were in good company:

Crick of DNA fame, Lord Kelvin, Astronomer Fred Hoyle and his renowned student Chandra Wickramasinghe were all proponents of the theory.

http://www.simpletoremember.com/vitals/did-life-form-by-accident.htm
http://www.pibburns.com/catastro/pansperm.htm
http://www.spacetoday.org/History/MillenniumTimeline/20thCenturyLate.html

So what's your sig line about then?

[greyl]

16. Nothing happened. I was unclear, I guess? :)

"I have liked this hypothesis for a while now" works too. :) I was referring to "from another world" more than " from Mars", though. For some reason, I don't consider Mars to be cosmic. She's practically next door! :)

Logically following the notion that simple life (or a crucial ingredient of life) arrived on earth from elsewhere in the cosmos, there is the notion that it happened more than once, and subsequently the notion that it is still happening with some(certain?) frequency(measured cosmically).
Anyway, liking the concept "cosmicseed" I have explored some of its numerous metaphorical possibilities. The "cosmicseed" as "new idea", for example. I did a few paintings inspired by the cosmicseed concept, and I've had a website named cosmicseed.net lying about in varying forms for a few years. My sig pic is a grey-scale of a reduced, cropped and filtered version of my first cosmicseed painting.
If I go any further, I fear a wormhole may appear between the Artists forum and this one. ;)

[Angry Girl]

17. Nice pics on your site & zinzang.com!

Slacker's Brigade yours? Trippy site - have to check it out in the daylight! z

[greyl]

21. :) Thanks a lot, Angry Girl.

I like your avatar a lot.

Slackersbrigade.com is a site I design for Robert Fegley, aka Zigbert Dingleflop. He does all the writing, photography, and music there. We've been online friends for a few years, and I think he deserves recognition, (his stuff would fit well on Out of the Box on NPR) that's why his site is in my profile. He's a rare human. Check out his music page for 10 more free mp3s.;) I recommend beginning with High Again.

edit: adding link /edit

Thanks much for your compliments. :) May I ask which pics at ZinZang are your favorite?

[TechBear_Seattle]

18. Greyl, your sig reminds me of a sig I use from time to time...

All Truth has three phases. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.

[greyl]

20. Yours reminds of the Gandhi quote:

"First they ignore you, then they laugh at you, then they fight you, then you win." :)

My sig line is a direct affront to the infamous "If you tell a lie long enough, loud enough and often enough, the people will believe it".

Truth. What a concept, eh? ;)

[smirkymonkey]

24. The question is, "Will they take some of it back?"

the Republicans and Fundies should be first to go.