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View Full Version : Sun, Earth Are Unlikely Pair to Support Life



Fraser
2009-Aug-10, 08:20 PM
We don't know how lucky we are — really. We know the interaction between Earth and the Sun is a rarity in that it allowed life to form. But scientists working to understand the possibility that it could have happened elsewhere in the Universe are still far from drawing conclusions. What is becoming clearer is that life [...]

More... (http://www.universetoday.com/2009/08/10/sun-earth-are-unlikely-pair-to-support-life/)

A.DIM
2009-Aug-10, 08:45 PM
"What is becoming clearer is that life probably shouldn't have formed here; the Earth and Sun are unlikely hosts."

Interesting.

So smaller, more plentiful, and longer-lived stars are thought to be more suitable for life to arise?
If so, I see no reason to continue holding to the notion life arose from nonlife on Earth.
If these scientists are correct, it suggests life is from somewhere else, somewhere more suitable.

Thanks!

SolusLupus
2009-Aug-10, 09:55 PM
That's a mighty large conclusion to draw from such a premise, A. DIM.

A.DIM
2009-Aug-10, 10:01 PM
Perhaps my understanding of the complexity of Earth's earliest life taints my perspective but the article rather unequivocally states "what's becoming clear," and then explains why, given the science involved.

Van Rijn
2009-Aug-10, 10:19 PM
Even taken at face value, the article didn't say anything about panspermia, A.DIM. This is more of your highly creative interpretation.

Nick Theodorakis
2009-Aug-10, 10:22 PM
As an aside, my inner Star Trek geek loves that the astronomer quoted in the story is named "Guinan."

Nick

Paul Beardsley
2009-Aug-10, 10:38 PM
A few thoughts:

Life from another star system would be just as vulnerable to the hostile environment of ancient Earth as anything "born" on Earth - and we know the life must have developed early enough to oxygenise the atmosphere.

James Lovelock, in one of his Gaia book, is pretty dismissive of the idea of the "fragile shield" and organisms' vulnerability to UV. He describes an attempt to eradicate life on a petri dish with a UV lamp, and the discovery that it's not as straightforward as it sounds.

Whereas hostile environments may be bad news for individuals, it makes things interesting when it comes to competing species. Indeed, it seems to me that the situation described could be the very mechanism that gave rise to complex life forms in such a seemingly short time.

The suggestion that the article supports panspermia is looking like straw-clutching.

KaiYeves
2009-Aug-10, 11:09 PM
Perhaps we're not really alive, then...

01101001
2009-Aug-11, 01:20 AM
If so, I see no reason to continue holding to the notion life arose from nonlife on Earth.

Is there some reason we should care about your strong inability to see a reason?


Thanks!

You're welcome!

GOURDHEAD
2009-Aug-11, 02:57 AM
It seems to be more a constraint on intiial (or subsequent) conditions than a veto of the formation of life. As soon as pools of water a mile or so deep formed on Earth there should have been more than enough protection of x-rays and ultra violet photons.

timb
2009-Aug-11, 09:36 AM
We don't know how lucky we are really. We know the interaction between Earth and the Sun is a rarity in that it allowed life to form. But scientists working to understand the possibility that it could have happened elsewhere in the Universe are still far from drawing conclusions. What is becoming clearer is that life [...]

More... (http://www.universetoday.com/2009/08/10/sun-earth-are-unlikely-pair-to-support-life/)


"The lack of an intrinsic magnetic field may be the reason why today Mars does not have an atmosphere."

Quality article that.

A.DIM
2009-Aug-14, 02:21 PM
Even taken at face value, the article didn't say anything about panspermia, A.DIM. This is more of your highly creative interpretation.

Perhaps, but how else should I read "what is becoming clearer is that life probably shouldn't have formed here?"
Life is here yet it probably shouldn't have formed here?
How would it have gotten here if it probably shouldn't have formed here?

Panspermia seems implied.

Paul Beardsley
2009-Aug-14, 02:25 PM
Perhaps, but how else should I read "what is becoming clearer is that life probably shouldn't have formed here?"
As, "it confounded expectations." Obviously.

It's like seeing someone walk away from a terrible car crash and saying, "You probably shouldn't have survived." The fact that you are talking to someone who shouldn't have survived does not support the existence of ghosts.

A.DIM
2009-Aug-17, 09:00 PM
As, "it confounded expectations." Obviously.

It's like seeing someone walk away from a terrible car crash and saying, "You probably shouldn't have survived." The fact that you are talking to someone who shouldn't have survived does not support the existence of ghosts.

Sorry, Paul, it wasn't so obvious to me.
Did the article say "it confounded expectations?"
No matter, to me the implication is clear.
And besides, I don't really view the formation of life as accidental as, say, a terrible car crash, especially one from which somebody walks away.

Van Rijn
2009-Aug-17, 09:37 PM
Perhaps, but how else should I read "what is becoming clearer is that life probably shouldn't have formed here?"
Life is here yet it probably shouldn't have formed here?
How would it have gotten here if it probably shouldn't have formed here?

Panspermia seems implied.

Did you read the beginning of the article?



We don't know how lucky we are really.

We know the interaction between Earth and the Sun is a rarity in that it allowed life to form.

(emphasis added) Whether you agree with the article or not, it is not about panspermia, or implied panspermia.

Van Rijn
2009-Aug-17, 09:39 PM
Quality article that.

In fairness, that was a quotation, not written by the author of the article. Hopefully, it was a verbal lapse.

timb
2009-Aug-17, 11:25 PM
In fairness, that was a quotation, not written by the author of the article. Hopefully, it was a verbal lapse.

Was the rest of it better? I stopped reading around there.

Paul Beardsley
2009-Aug-18, 06:13 AM
Sorry, Paul, it wasn't so obvious to me.
Did the article say "it confounded expectations?"
No matter, to me the implication is clear.
What an article implies and what a reader infers are not always the same thing.

There are mysteries about life. That doesn't mean every mystery is evidence of panspermia.


And besides, I don't really view the formation of life as accidental as, say, a terrible car crash, especially one from which somebody walks away.
That was not the point of the analogy.

A.DIM
2009-Aug-18, 02:53 PM
Did you read the beginning of the article?
(emphasis added) Whether you agree with the article or not, it is not about panspermia, or implied panspermia.

Yes, I read it; as you say, the article is not about panspermia.
Apparently is it about how lucky, or special, life on Earth is, how rare.
"What is becoming clearer is that life probabaly shouldn't have formed here" yet it is here, and so we assume it originated here, which reinforces the luck and rarity attached to its presence.
How special we are.

A.DIM
2009-Aug-18, 03:00 PM
What an article implies and what a reader infers are not always the same thing.

I agree, but let me ask, did you infer "it counfounded expectations," or was that implied in the article?

There are mysteries about life. That doesn't mean every mystery is evidence of panspermia.

Certainly; I don't think every mystery of life is evidence for panspermia.


That was not the point of the analogy.

Well, I didn't find it very analogous.

clint
2009-Aug-18, 07:10 PM
Whereas hostile environments may be bad news for individuals, it makes things interesting when it comes to competing species. Indeed, it seems to me that the situation described could be the very mechanism that gave rise to complex life forms in such a seemingly short time.

Hmm, so following the same logic,
this might mean that primitive life in orange dwarf systems is relatively common,
but complex life very rare.

OTOH, if primitive life was much more likely to arise in orange dwarf systems,
(AND we already know orange dwarfs are much more common than sun-like stars)
then complex life might still be more likely to be found in orange dwarf systems...

Does this make any sense?