New research paper says - Mars life unlikely

Bill White · 2002-12-06 11:48:28

Film at 11. . .

Anyway, for those of you who do not routinely read spacedaily, here is a link.

Is this paper online anywhere? A short quote from the article.

"There apparently were some brief warm and wet periods on Mars, but we believe that through most of its history, Mars has been a cold, dry planet," said Segura, now a visiting researcher at NASA's Ames laboratory in California.

Nida · 2002-12-06 13:16:03

What film're you talking about?? You're joking?

Bill White · 2002-12-06 14:19:11

Film at 11. . .

Some web discussion groups use "film at 11" as a snappy slightly sarcastic way of saying "to re-state the obvious"

11 means 11 pm E.S.T. when the east coast runs its usual local TV news shows

Here in Chicago, by the way, its the 10 o'clock news and not the 11 o'clock news. . .

Sorry for the obscure reference

Josh Cryer · 2002-12-06 14:46:14

Hehehe, three serprate topics about this. It's a farily interesting discovery, it seems. You know what, though? If anything, this theory would lead to evidence that life originated on Mars and was seeded on earth!

dickbill · 2002-12-06 15:16:08

I am not surprised. I never believe in that theory of a northern ocean in a far remote martian past.
4 billions years ago, the sun was much fainter as today (don't ask me the ref, but there is also a mention of that in the original paper in Science ((of this week))
Sources of energy to counterbalance that faint sun could have been volcanism and radioactive decay, plus a thick, greenhousing atmosphere, without those putative ingredients, water was just ice on Mars.
Now the authors in that science paper (Teresa L. Segura, Owen B. Toon, Anthony Colaprete, Kevin Zahnle) said that large meteoric impact created just enough energy to defreeze that ice from time to time, sometimes for thousands of warm years but not much more. Consequently they add that life was unlikely to appear in so short periods of warm time.

Ice or Water, extinct life or not, that change nothing for those who support terraforming/bioengineering Mars.

HeloTeacher · 2002-12-07 08:38:48

The only significance to this forum that I see in this research is the fact that although the planet was warmed, it continues to regress to a frozen state.

This indicates that there is a mechanism not currently understood that provides the cooling feedback once the planet is warmed.

dickbill · 2002-12-07 21:22:03

The cooling process is known, it's just the thermic dissipation, that is, more thermic energy dissipated than energy received from the sun, because of the abscence of a green housing atmosphere. The radiatif bilan is negative on Mars, but quantitatively, I don't know how far it is from a null bilan. Probably not very far since it has been said that very little of green housing gaz, such as CFC, in the Mars atmosphere, would trigger a global warming.

GOM · 2003-01-20 22:10:23

I believe there is life on Mars. It might all be microscopic, but I'll bet it's there.

We won't know for sure until we send some people over there, imo. Unfortunately that's going to be some time well into the future. At our current rate of progress, I doubt we will make it in my lifetime.

.02

dickbill · 2003-01-30 17:49:52

"i believe there is life on Mars"

well, it's gonna be like in the Kim SR trilogy, until the last rock of the last crater or volvanic vent is turned upside down and scanned, there will be always someone to claim that life is somewhere on Mars.
I have to say however, that if the nanobacteria found in meteorit AHL 84001 are really nanobacteria, then the bacterial life was pretty abundant long time ago, as we don't expect that the impactor which delivered the ALH meteorit precisely felt on the only 'bacterial" spot on Mars. In this case it should be pretty easy to find other nanobacterial traces on MArs...but who knows, maybe this impactor actually felt on the only attempt for life to arise on MArs, sterilizing the first and last Martian bacteria and sending the microfossills to Earth, as a postalcard.

Josh Cryer · 2003-01-30 22:04:02

Well, I didn't quite like that bit in KSR's book. A true indication of life, would be the discovery of fossils! At first, before colonization happens or any of that, obviously living life would be an amazing discovery, but just because people come and contaminate everything later on, does not mean the search for life has to end. Fossilized remains are sure to exist, had life existed there.

Shaun Barrett · 2003-01-30 23:30:52

Hi Josh!
I agree with you that if life existed on Mars, there will surely be fossil evidence. And a fascinating discovery it would be too!

I take that argument a little further, though, in asserting that if life existed on Mars in the past, it will certainly still be there in some form today.
Life - particularly microscopic bacterial life - is extraordinarily hard to kill off once it's established.

Josh Cryer · 2003-01-31 00:18:05

Well, I'd say it depends on how long they had to adapt to whatever changes occured to cause Mars' current state. If it was the failure of a magnetic field, it's suspect whether or not they could have adapted in time, especially if they were a relatively new form of life.

Then again, it's quite possible life, had it formed on Mars, formed deep underground, where they would not be susceptible to the loss of a magnetic field. They could have existed there, and could still exist there, even, under geothermal energies or whatever. In fact, it's been argued that we formed deep within the sea, so yeah, I might well agree with you Shaun on that particular point.

I think that surface life is non-existant, though.

dickbill · 2003-01-31 14:35:20

Shaun, life is difficult to kill, but it's possible. It has been said that in its early times, just after the earth surface was cool enough to sustain life, life happened on earth, maybe 3.8 billions earth ago (stromatolith fossils). Earlier than that, the first living "things" on earth would have been most likely sterilized by the meteoritic bombardment.

beside that, I've also read that some forms of life on earth are so exotic that some people consider them as originally martian. Like Deinococus radiadurans which is able to whistand thousands of time more radiation than we can in resealing its broken pieces of DNA.

Because, what the point for this bacteria to resist a radiation level that doesn't exist on earth ? Biologist say that actually it's a resistance to intense dehydratation or oxydation, which break the DNA strands as well as radiations...but earth is a pretty wet planet... so Deinococus radiodurans ability to resist radiations might as well be usefull on Mars, where radiation are very intense. Against that martian origin is the fact that the genome of this bacteria is very similar to other procaryotic genome. Science fiction maybe, but it's funny to mention that story.

Shaun Barrett · 2003-01-31 20:19:48

There's no way to deny that Josh might well be correct in saying early Martian life could have died out due to one cause or another.
And, of course, Dickbill's argument that, while life is tough, it isn't indestructible, is equally valid.

But I'm very impressed by the fact that even if just one bacterium survives a catastrophic environmental event, a whole planet can be repopulated with bacteria in a short time.
Apparently, bacterial 'generation time' (interval between doublings) can be as short as 15 minutes! Even if we take a conservative interval between doublings of, say, 4 hours, in one day 1 bacterium can become 64 bacteria. A day later there'll be 4096. And at the end of the first week (assuming enough living space and nutrient) we could have approximately 4.5 trillion bacteria!!
If such bacteria (or archaea) live in a region of the Martian crust where geothermally-warmed water percolates through fissures in the rock, billions of their number could quite easily be transported large distances.
A year after the catastrophic event which destroyed all but one bacterium, enormous areas of the Martian crust could be repopulated with countless organisms. And, with that rate of reproduction, random mutations and natural selection could already have produced new types of bacteria - new species could already be developing to fill empty ecological niches.

And we also have impact transfer between Earth and Mars as a second means by which organisms could cheat cosmic catastrophes. Smaller impacts were more common than planet-sterilising ones (still are, thank God! ). And it's becoming apparent that large chunks of relatively undisturbed Mars have been delivered regularly to Earth, and vice versa, throughout the history of the solar system. While one planet was sterilised, the other could have been harbouring life waiting to be re-established on the first.
Even if both Mars and Earth were pulverised simultaneously by asteroids large enough to completely melt the crust of each, there would still be large numbers of rocks containing dormant organisms in transit between the two planets. Some would be landing on Mars and Earth millions of years later, after the crusts had re-solidified.
It has even been theorised that millions of mildly shocked rocks, containing viable bacteria, could have been lifted into unstable orbits around Earth by an impact big enough to kill all life on or under the surface. As the unstable orbits decayed over hundreds of thousands or millions of years, life would have been restored to the surface by those returning rocks. This idea has been used to explain how life on Earth could have established itself so quickly after the 'Late Heavy Bombardment' 3.8 billion years ago.

Of course, I never originated any of these ideas. I know of them only by reading about the research being done by people much smarter than I am! But these ideas do hold water, in my opinion, and I've thought long and hard enough about them to come to the conclusion they must be right.
There is no doubt in my mind that DNA based life, perhaps indistiguishable from Earthly forms, will be found on Mars. (Though maybe, as Josh surmises, only underground.)
To me, the logic is simply inescapable. And I'm not alone in thinking this, by any means. The only real mystery, is why it's taking people so long to assimilate the recent revelations into their view of things!

Josh Cryer · 2003-01-31 21:22:56

Yeah, even if mars has been volcanically dormat for millions upon millions of years, there would still be plenty of thermal activity. And all we need is liquid water for life to exist. That's the only real prerequsite.

If DNA based life is found on Mars, and we can prove fairly conclusively that a bio-transference did take place, that would have huge implications.

dickbill · 2003-02-01 14:17:18

I hope Shaun is right, that we can find one day dormant organisms on Mars. And in such a case, it would be interesting to integrate a little of their genome in ours, to make the incomming humans more martians, if it is proven that they are really martian, because now the frontier between earth and Mars becomes fuzzy in terms of who comes from where first.
About that theory of panspermy, the most intersting point is that the first forms of life on earth are precisely impossible to find on earth because of the tectonic subduction or crust melting, but then we should expect to find them in meteorites, either on the moon, Mars or just in space. It would be so interesting to find those early putative RNA replicators, Haldane coacervats, whatever they are, frozen in space waiting for us.

dickbill · 2003-06-23 13:59:59

I have to say however, that if the nanobacteria found in meteorit AHL 84001 are really nanobacteria, then the bacterial life was pretty abundant long time ago, as we don't expect that the impactor which delivered the ALH meteorit precisely felt on the only 'bacterial" spot on Mars.

It's not fair to cite myself, however, I think I hited a point here: If the ALH84001 meteorite (you all remember the picture of these rod-like bacteria right ?) really contains microfossils, then life was abundant on Mars, as we don't expect to be particularly lucky with one meteoritic sample. It follows that it should be easy to find similar fossil evidence of this abundant past life with the rovers. Everybody agree with that ?

And also, to continue the discussion with BGD in the containment thread, about the archae kingdom, here is a link:
http://www.earthlife.net/prokaryotes/archaea.html#1

Gennaro · 2003-06-23 16:32:32

Yes, and if we don't easily find similiar fossil evidence, then by the same token, ALH84001 goes down the drain.
Dare I hope that Beagle 2 on ESA:s Mars Express, will have strategic importance for the verification process?

dickbill · 2003-06-23 16:58:04

Yes, and if we don't easily find similiar fossil evidence, then by the same token, ALH84001 goes down the drain.
Dare I hope that Beagle 2 on ESA:s Mars Express, will have strategic importance for the verification process?

Beagle2 could fall on a wrong spot, so if it doesn't discover anything, that won't prove there is no life on Mars.
The mobile rovers can at least move to interesting spot. I think their camera/microscope has a resolution of 50 micrometers (from memory, it was something in this order), that's not enough to directly see the equivalent of the ALH84001 nanobacteria, in addition, even bacterial filaments or other microorganisms bigger than 50 microns needs to be fossilized in the rock (or alive). We would be lucky to be fixed on the issue of life on Mars with just these missions but who knows, we might be surprised.

GOM · 2003-08-17 14:27:07

Dare I hope that Beagle 2 on ESA:s Mars Express, will have strategic importance for the verification process?

First, let's hope it actually makes it to Mars.

Shaun Barrett · 2003-08-17 19:48:36

Today I have on my conspiracy hat (a remarkably good fit, too ... ! ).

Just suppose that a high-level NASA group had decided that the discovery of life on Mars - any life, whether Earthlike or not - would spark the mother and father of all Greenie Crusades against any further exploration, especially by humans.
This would explain the lack of any life-detection instruments on the two MERS; NASA would be keen to avoid having to announce Martian life for as long as possible, even if they knew right now that it exists, so as to enable the development of space transportation systems capable of getting us to the red planet before the sh** hits the fan! Once Mars is ruled out-of-bounds by the almighty environmental movement, it would be much harder to elicit funding from congress for deep space missions because, of all the potential targets, Mars is surely the most glamorous and inviting. Take away Mars and you cut the heart out of space advocacy, at least for many people.

But what of Mars Express and Beagle II ?
Would NASA's influence be enough to stifle any ESA discovery of Martian life or might Europe ruin future Mars exploration by inadvisedly 'letting the cat out of the bag' too soon?

Just an idle thought! ???

Free Spirit · 2003-08-17 20:45:55

Us conspiracy hounds have already shot down NASA's and the Free Masons' attempt to keep those cities on Mars secret so we know NASA already knows life had existed there. But just hypothetically speaking, I think NASA would be highly inclined to reveal the discovery of microbial life on MArs since it would spark a lot more public curiosity about Mars and hence more pork for Mars projects. I could be wrong but judging how unsuccessful the extreme fringe of environmentalism has been in preventing launches of RTGs I don't think the greenies would be a big obstacle. Also, as you already hinted at, I doubt the secret could be kept for long since a lot of countries apart from the EU and USA such as Japan and China will probably be sending gaggles of probes on their own. NASA probably wouldn't want to lose the glory of claiming it found life first.

Oh yeah, don't forget about the media circus that was revolving around that Martian meteorite. I believe the scientists who were working on it were paid by NASA so that should be evidence that NASA isn't out to keep discoveries of unintelligent life secret.

Shaun Barrett · 2003-08-18 06:45:28

Free Spirit writes:-

NASA probably wouldn't want to lose the glory of claiming it found life first.

But then how do you explain the absence of any experiments aboard the MERs which could detect life?
This is a fine opportunity to at last prove or disprove the persistent argument that Viking found living organisms in the Martian soil. But what have we got? Robot geologists; not robot biologists!
I have nothing against geology. It's a vital part of our attempts to fathom Mars' past history. But doesn't it seem astounding to anyone else here that 26 years after an inconclusive but tantalisingly suggestive Viking result, which may have detected life on another planet for God's sake(!! ), NASA has never once tried to clarify that possibility?!

Every time you read anything about exploring Mars, you hear the same story about how we're going to look for life. But we never do. Even when we get the chance. ... Like now, for instance!
It's like some kind of magicians' trick. You know ... keep the audience concentrating on what your right hand is doing, while your left hand is doing something completely different.

"Yeah, the most important question you can ask is whether there is life on other planets, and that's what we're going to find out on Mars." -[NASA]
"Oh, so our latest probes will pick up where Viking left off and get a definitive answer?" -[YOU AND ME]
"Umm ... Well, actually, no!" -[NASA]

The whole thing is more than a little odd, don't you think? If there is any logic to NASA's actions (or inaction) it must be based on something we're unaware of. I get the distinct impression sometimes that we're being told no more than we need to know! ???

dickbill · 2003-08-19 11:03:27

I want to mention a research paper in Science of this week:

"Extending the Upper Temperature Limit for Life"
by Kazem Kashe and Derek R.Lovley

The authors have found an (likely an "archae" according to them) bacteria which thrive at 121 degre centigrade !, in an hydrotermal vent of the northen Pacific ocean. The vent itself is at 300 degre C but the organism, called strain 121, reduces Fe3+ in Fe2+ in the form of....magnetite and this at a crazy 121 degre C !

The authors still expect to find something growing at higher temperature !!!!
Now, I have one question, the DNA double helix is supposed to be denatured, meaning that the helix are separated, at about 100degre in normal (non thermophilic) organisms, how strain 121 keeps its DNA double strand at 121 degre ?
I know that at the begining, people expected to find a GC rich DNA in thermophilic archae, because GC rich DNA makes the DNA harder to denaturate. Surprise, it is not at all the case ! the archae DNA (the one I read at least) was AT rich ! making the DNA easier to denaturate. This didn't make sense in a thermophilic organism, until researchers found that the DNA was kept double stranded by proteins and by hypercoil special configuration. Well, here at 121 degre it is even difficult to imagine how the proteins themself keep their conformation stable. I bet that we will be surprised again.

Of course, this is relevant to Mars and the Sinus Meridiani magnetite rich region.

dickbill · 2003-08-19 13:36:17

The vent itself is at 300 degre C but the organism, called strain 121, reduces Fe3+ in Fe2+ in the form of....magnetite and this at a crazy 121 degre C !
Of course, this is relevant to Mars and the Sinus Meridiani magnetite rich region.

Sorry, S. Meridiani is a Hematite rich region, not Magnetite, but the parallele still stands, since magnetite is also found in bacteria (like in this case for strain 121) and might be also present in the S. Meridiani.
Magnetite and hematite are two different iron oxydes, go to :
http://www.birdnature.com/nov1899/ores.html
it says: "Hematite differs from magnetite in representing a higher degree of oxidation. It is often found, as indicated above, in beds distributed in close conjunction with those of magnetite. "

I just check, it is Opportunity who goes to Sinus Meridiani, with its deficient "iron" spectrometer. Hopefully engineers said that the spectrometer can still function in reduced capacity. So let's hope that the rover will be able to analyse the hematite of sinus meridiani.

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