Martian meteorite surrenders new secrets of possible life

[Marcel]

Wouldn't it be ironic if that meteorite contains the only extant fossils from Mars? :lol:

 

[RisingFury]

I'm not saying no fossils can survive. I'm saying that no surface fossils can survive... fossils that we have a chance of finding, using our probes.

Even so, the explanations for the loss of atmosphere and odd shape are just one of the possibilities.

And I can think of several large scale events that might deform the planet. Look at Venus, for example. Weak magnetic field, so the solar wind, which is much more powerful at that distance erodes it's atmosphere, yet it's much thicker then Earth's. Also, it's year lasts longer then it's day and it rotates BACKWARDS. That cannot be the result of a planet in the process of being tidally locked - Mercury is in that process, with it's day:year ratio being 3:2.

Then look at Uranus... it rotates on it's side. The explanation is not know, but it is likelly that early on during the formation, a large body struck it and tipped it over. We can say it was very early in the creation, given that some of it's moons - the ones not caught later on - orbit over the equator, with the same tilt...

Also, we have one of the theories that Earth's Moon was formed from a giant impact and some good evidence to support that...

The point of all this is that the early solar system was quite a shooting gallery of high calliber bullets and I can think of various large scale impacts.

 

[T.Neo]

And I can think of several large scale events that might deform the planet. Look at Venus, for example. Weak magnetic field, so the solar wind, which is much more powerful at that distance erodes it's atmosphere, yet it's much thicker then Earth's. Also, it's year lasts longer then it's day and it rotates BACKWARDS. That cannot be the result of a planet in the process of being tidally locked - Mercury is in that process, with it's day:year ratio being 3:2.

Then look at Uranus... it rotates on it's side. The explanation is not know, but it is likelly that early on during the formation, a large body struck it and tipped it over. We can say it was very early in the creation, given that some of it's moons - the ones not caught later on - orbit over the equator, with the same tilt...

Also, we have one of the theories that Earth's Moon was formed from a giant impact and some good evidence to support that...

The point of all this is that the early solar system was quite a shooting gallery of high calliber bullets and I can think of various large scale impacts.

Yes. Large scale impacts have indeed occured often in the early history of the solar system.

What I'm saying is that I can't see the evidence for such an impact on Mars. I never said it couldn't happen.

I'm not saying no fossils can survive. I'm saying that no surface fossils can survive... fossils that we have a chance of finding, using our probes.

Some surface fossils should survive. That and deep-layer fossils could be uncovered by impact events.

And well, if you want to search for fossils using probes, good luck. Maybe in a few centuries we'll have Martian Paleontological Terminators available for use. :rofl:

 

[Marcel]

The article states that the rock was knocked off of Mars 16 million years ago. If these are fossils, this thing was already ancient when that occurred. I'd really like to know how old this object is.
Another thought, if there is life on Mars and we go there, we will contaminate it. How does that prospect affect our exploration plans?
As to the question of whether alien life would have DNA, I look at the process of chemical evolution that has occurred in the universe thus far. The elements necessary for life were forged in several generations of stars as part of a natural process. Organic chemicals formed when these elements combined, again as a natural process. I wonder if DNA formation is again part of the same natural process. There seems to be an inevitability about this whole thing which borders on religion. There's also the concept that life may have formed in many places and may have traveled between planets this way. If you find DNA on Europa, who knows where it originally came from? It's possible that those are fossils that are the descendants of an early life form that evolved on Earth!

 

[JamesG]

I agree the biggest problem with this whole situation is that it is an example of jumping to conclusion and assumption based on scant evidence and preconception or even worse ulterior motive.
NASA which derives its reason for existence (and budget) on space exploration, trots out a shaky hypothesis that some rock that could have originated on Mars and that kinda looks like it has a fossil, and we in the public and the politicians are supposed to get all excited and open the coffers to whatever they like. A bit to contrived to me. Much like "climate change".

 

[RisingFury]

There are very real advances in science and technology and a huge benefit to the economy. Particle physicists keep asking for more money to build more powerful accelerators and in the process, they pretty much invented the internet, now worth billions of dollars. They've paid for their own experiments ten times over.

---------- Post added at 02:59 PM ---------- Previous post was at 02:38 PM ----------

I have one more thing to add...


Accusing scientists of forging their data and releasing misleading conclusions is about as low as one can go.

Sure, people do that all the time and a nice example of what happens to those claims is the cold fusion and the fusion through sonoluminescence. The scientific arena is the most hostile place for one's credibility and believe me, no scientist wants to destroy their credibility for nothing.

There is evidence to support the conclusion that that is a fossil. It's been proved that the rock is from Mars. It's been proved that the shapes are not the result of the initial impact event, reentry or secondary impact event. The shape of the fossil is almost identical to what some Earth bacteria leave behind. There's still a chance the the rock might have been contaminated, but that possibility has been proved to be small. Therefore, there is good evidence towards that conclusion.

Though like I said, one rock won't prove life existed on Mars. We need to find the same fossils on Mars to prove anything definitively, but it does give scientists good reasons to look around.

 

[Hartmann]

I think that is not a reliable proof .

assuming that is a real martian rock, it could be contaminated after crash on the earth. Another possibility is an ancient earth rock in orbit that fall again to the ground like a meteorite.


the only way is go to mars and take samples, but in what place ? could be really representative , perhaps no exist life in every place and only in some spots

 

[RisingFury]

Of course this rock is not conclusive proof. Nobody is claiming that... what it is is just further evidence.

They have a way of proving the rock is from Mars. I haven't read the study from 13 years, but my guess would be to look at the composition of the rock and look for certain markers like the amount of water and iron in the rock. It's known Martian rock contains large concentrations of rust - iron oxide...


It's very unlikelly that the rock was a satellite of Earth. There were several theories, about a small, second natural satellite of Earth. Several searches were done and nothing was ever found. There's a good reason for that. Our Moon is very massive and 5th largest moon in the solar system. Over time, it would have completelly cleaned out Earth's vicinity.

If you look at Mars, it has two satellites and they don't kick each other out, because their gravity is entirelly dominated by Mars.


Concerning the "where to take samples" question...

If you're looking for evidence of life, the most preserving area would be the ice caps. They'd be relativelly easy to dig into and provide a place where any evidence would be frozen in dry ice. However, it's worth noticing that Mars wobbles in it's axis. Since Mars has no large moon to stabilize it, it's axis varies between 90° to -90°, relative to the plane of the solar system. That means ice caps would appear and disappear over time and would thus be able to preserve only the last 10 or 20 million years...

 

[Jake]

No offense intended, but your statement is IMO utterly absurd- a few microbes on Mars has nothing to do with the Fermi paradox.

No, I think Andy44 meant to refer only to The Great Filter mostly, not Fermi's Paradox. The filter uses as a reasoning base the paradox. It splits the evolution of life into 8 steps, #7 being intelligent, tool-using, sentient life. The filter postulates that one of these steps is extremely unlikely, otherwise step #8, the explosion of colonising life, would make the Milky Way full of intelligent, alien life and we were bound to notice a trace or two of it by now.

Human civilization has already successfully passed through the first 7 steps. If these steps were the more likely ones with #8 being the unlikely one, then we should start worrying. Thus, The Great Filter implies at some levels that finding traces of multicellular (not microbes) life on Mars means a grim future awaits us. It means that the first 6-7 steps are the likely ones, with #7 or 8 being the ones where the great filter is. That's where civilizations are curbed.

Now, I'm one of the more skeptical guys, for me life in the galaxy (if any) is by no means what we see in Star Wars or games like Ass Effect, we tend to anthropomorphise eveything too much, or at least adapt it to our way of thinking. However, I don't even dare imagine we're the only sentient beings in a Universe this big. And the Paradox/Filter? I think they too are rooted too much in our limited POV to have a solid argument. But it makes for a nice exercise in skepticism.


BUT OF COURSE THIS IS JUST A BUNCH OF HOGWASH AND WE'RE IN FOR A WORLD OF **** WHEN THE REAPERS COME FOR US HURR DURR

[edit] Lol, ninja'd.

 

[Andy44]

"There is good reason to hope there is not, and never has been, life on Mars: The Great Filter and Fermi's Paradox. "

No offense intended, but your statement is IMO utterly absurd- a few microbes on Mars has nothing to do with the Fermi paradox.

Modern instruments are simply not able to detect life on other planets. Stand 50 light years away from Earth with one of our best telescopes and you'd be hard pressed to find trees or animals, let alone microbes.

Stand a meter away from a counter-top, and find the teeming microbes on the surface (without the proper equipment, of course). It will be equally difficult.

Fermi's paradox only applies to intelligent civilisations (and pretty advanced ones at that). Don't rule out a very possible (and I mean VERY possible, in terms of microbial life) thing because you don't see it building Dyson spheres and interstellar lasers.

Of course, when it comes to intelligent life, this sums it up pretty well:
<snarky picture>

Whay is it that when people want to say something obviously condescending, they always preface it with "no offense intended"?

Fermi's Paradox applies to "intelligent" civilizations, of course, but in order to have lots of intelligent civilizations, there has to be lots of life-supporting planets. A very small minority of which will develop intelligent life.

If Mars was/is a life-supporting planet, and say, Europa turns out to be one as well, then it would appear that life is much more common than we believed, common enough to arise on multiple bodies within a single star system. Therefore, there should be a few more intelligent life forms out there, and we still see nothing.

Something "filtered" out the life we should be seeing in the sky. We humans are subject to the same "Great Filter"; the question is whether the GF is in our past or in our future.

If the GF weeds out life in its primitive stages, we're good to go. Even better if the GF prevents life from forming in the first place, since we're long past that.

But if the GF is applied after life has formed, then we may not be out of the woods, yet. In this case, we could be wiped out before we go interstellar and, just as we see nothing in the sky, no aliens out there will ever see evidence of us in the sky, either.

Lots of life in one star system supports the idea that the GF is ahead of us and that our chances of going interstellar are very slim.

 

[tblaxland]

Here are some of my thoughts on the above discussion:

1. If their is, or has been, life on Mars, what is the relative probability that it has a common origin with life on Earth, compared to the probability of it evolving independently? I think it is more likely to share a common origin, but that is more of a hunch than a reasoned conclusion since I don't know enough about these things. Maybe some of you guys do... Anyway, if life on Mars did not evolve independent of life on Earth, doesn't that water down the idea that "life on Earth" + "life on Mars" = "increased probability of life on extra-terrestrial planets"?

2. Why does the Great Filter need to be applied at some consistent position in a species evolution? Consider two independently evolving species in different star systems. If one is wiped out early (<step 6) and the other late (step 7), what does that say about the probability of any species reaching step 7? Why does the great filter always need to be applied at the same "step"? I see no logical reason for it.

3. I think the premise of "step 8" of the Great Filter is erroneous. I just can't see any species, regardless of the advanced state of its evolution, going of to colonise other stars. Maybe that just means I see the Great Filter lying between steps 7 & 8...

 

[Rocketman527]

I just can't see any species, regardless of the advanced state of its evolution, going of to colonise other stars.

I don't see why they/us wouldn't. Nice, habitable planets are bound to be out there, why not go?

 

[Andy44]

2. Why does the Great Filter need to be applied at some consistent position in a species evolution? ....


3. I think the premise of "step 8" of the Great Filter is erroneous. I just can't see any species, regardless of the advanced state of its evolution, going of to colonise other stars. Maybe that just means I see the Great Filter lying between steps 7 & 8...

Sounds like you just answered your own question.

If we take Fermi's assumptions as correct, than the Great Filter certainly lies before step 8; exactly which step it lies at doesn't matter. You either get off your planet of origin, or you die a relatively (in the time scale of the universe) quick death.

I hadn't heard of the "8 steps" before this thread. But to me it doesn't matter, the going-forth-and-colonizing-the-galaxy step is the only one that really counts in the long run.

 

[tblaxland]

Sounds like you just answered your own question.

Lol. Often happens when brain farting

 

[ijuin]

I'd think that the jump between 5 and 7 would be the hardest part. I expect that we'll see stuff analogous to bacteria just about anywhere that has had favorable conditions for longer than one or two billion years, but that anything with an actual brain (i.e. smarter than earthworms) would be comparatively rare, and having the brainpower for abstract language even more rare.

For timescale comparison, brain-bearing creatures have really only been around since the Cambrian (1/5 to 1/6 of life's existence on Earth), and creatures that have both at least 1/4 of human brain mass and 1/4 of the brain mass per body mass as humans only appeared in the last 10 million years, with the creation of grammatical language as we know it being no earlier than Homo Erectus (Pleistocene).

 

[Andy44]

I've never understood the fascination of brain size and relative mass. Whales have giant brains, so what. Let me know when they fly in space (without Spock and Scotty's help). Parrots have much smaller brains, but a few exceptional specimens are smart enough to form sentences, such as the famous Alex the African Gray.

 

[Marcel]

As far as Fermi's Paradox goes, I like Carl Sagan's reply, "Perhaps we're the first." We may become one of the Ancient Ones that will guide the younger races' evolution. We may become the Vorlons, or perhaps this has already happened. Perhaps flying saucers are real, or perhaps the whole thing is a load of dingo's kidneys. We have a heck of a lot to learn, and it's nice to be here for these discoveries. I'm eagerly awaiting the official announcement to find out what's really going on!
I'd also like to point out that these guys were thinking about nanobots colonizing the galaxy. In the early 1940s. During their off time. Wow!

 

[ijuin]

I've never understood the fascination of brain size and relative mass. Whales have giant brains, so what. Let me know when they fly in space (without Spock and Scotty's help). Parrots have much smaller brains, but a few exceptional specimens are smart enough to form sentences, such as the famous Alex the African Gray.

As long as it contains the right mix of parts (such as having the majority of its neurons devoted to processing and reacting to external stimuli rather than devoted to keeping the body running), the more important number is the ratio of brain size to body size--humans have about 2% of their lean body mass as brain, whereas whales and elephants, despite their greater brain mass, still have less than 1% of their body mass as brain. The bigger your body, the more brain is needed just for "housekeeping" to coordinate all those other cells in the body, which is why a rat or a parrot can be as intelligent as a dog despite the lower brain mass.

 

[T.Neo]

Whay is it that when people want to say something obviously condescending, they always preface it with "no offense intended"?

Because it is condescending, and I do not wish to offend you.

Fermi's Paradox applies to "intelligent" civilizations, of course, but in order to have lots of intelligent civilizations, there has to be lots of life-supporting planets. A very small minority of which will develop intelligent life.

Fermi's Paradox isn't (widely) applicable; 1, because we lack the tech to discover civilisations like our own and 2, because we're probably using the wrong methods to search for more advanced ones.

Space is big, dismissing the existence of alien species because they don't land on the whitehouse lawn or write "Coke Adds Life" in the sky is shaky at best.

Secondly, evolution and life are VERY difficult things to predict. While I think the possibility of complex life (read; multicellular like plants animals and fungi) is quite high if the conditions are correct (look at Earth- there is a high chance that we just made it.), the chances of intelligent life evolving are rather smaller- it only evolved once here (as far as we know, although the possibility of other prehistoric sophonts is slim), although other species such as elephants and the aformentioned parrots have come close.

Therefore, there should be a few more intelligent life forms out there, and we still see nothing.

Again, because we don't have the ability to detect them. If life is found within our solar system, it does not suggest that it generated independantly.

But if the GF is applied after life has formed, then we may not be out of the woods, yet. In this case, we could be wiped out before we go interstellar and, just as we see nothing in the sky, no aliens out there will ever see evidence of us in the sky, either.

Lots of life in one star system supports the idea that the GF is ahead of us and that our chances of going interstellar are very slim.

One needs not make life extinct to prevent it evolving into higher forms; evolutionary conditions (such as those on Mars and Europa) will not allow complex life to evolve.

If there is a "Great Filter", it most likely lies either in the evolution of complex life, or the evolution of the sophont species themselves.
You could have an entire planet for example where the multicellular macroscopic life is similar to fungi or plants with no "animals" in sight- no intelligent species could evolve from a tree or mushroom since they lack intercellular communication systems which could evolve into brains.

 

[JamesG]

Since we only have very incomplete knowledge of one example of biological evolution, any speculation about life elsewhere is just that, speculation.

For all we know, non-carbon based life (silicates and weirder) may evolve in the reverse order, they start with brains and develop teeth, legs and claws later.