Have you seen the ESA's newest photo of Mars' surface? Check out this nice shot from the Mars Express Orbiter:

Nooks and Crannies! (http://www.newscientist.com/news/news.jsp?id=ns99994582)

If we can't prove there is life on other planets, at least we can prove that our best English Muffins were inspired by other planets.

Nooks & Crannies ... ummmmmm *drool*

:hmm: How does that look like an English Muffin?

It is an interesting shot though, I'm amazed that they finally got a thingy to land there, after all those failed attemps.

RoTKu wrote: I'm amazed that they finally got a thingy to land there, after all those failed attemps. It didn't land...It's just an orbiting satellite. ;) :p

Don't get too excited about life on Mars. The sheer improbability of it is mind-boggling. The odds of life happening twice in the known universe, let alone in the same solar system, are trivially small relative even to a wildly exaggerated possible number of planets.

If there is life to be found on Mars, chances are it either came from Earth, or vice versa. We exchange several tons of cosmic debris every year with the red planet, and there's a strong possibility that at least some of that debris carries fossils or perhaps even microbes capable of surviving in space for a while.

I was going to go into the science on this, but it'd take too long and I'm tired. Take a look at the Fifth Miracle by Paul Davies. (And before anyone gets their knickers in a twist and accuses me of Copernicanism, know that Davies is a widely published atheist physicist.)

How does that look like an English Muffin? It doesn't, but there are English Muffin commercials here that speak of the "nooks and crannies" in their product.

/me has too many comercials going through my head!

When you see the variety of life on our planet, I can't imagine we are the only habitable planet with life on it in the Universe. When you think that one planet in ten revolving around a yellow sun has such a myriad of life and you look up at night to see billions and billions of stars...How can you not think the Universe is TEEMING with LIFE?

But what is "life"?

But what is "life"? You know, strip malls, fast food restaurants, sports teams, etc...

Any kind of life, microbial, sentient, whatever...Just life beyond our planet!

Does a virus count as "life"?

I guess so...I'm no scientist.

We need Gonzago to come back with his 'scientific' reasoning for all this.

All right, off we go...

Keeping in mind that there is absolutely nothing religious about what's coming.

Either one of two things are true: either there is a scientific law mandating life that we don't yet know about (in which case it's a safe bet there's life elsewhere), or life on earth is a result of chance.

If life is a result of chance then its variety on earth is a non-issue. What we know about life is that once it starts, there's no stopping it. According to this argument, every living thing on the planet has a common ancestor. From that common ancestor, natural selection has differentiated the species to create living beings that range from human beings to blowfish to fireflies to microbes that live off sulfur expelled from superheated volcanic vents at the bottom of the sea.

So the question lies in the probability of the spontaneous creation of the common ancestor, the first truly "living" thing on earth.

Atoms know how to do one thing, and one thing only: crash into other atoms. Now, the odds of any conceivable array of atoms *accidentally* crashing into one another to produce something even as sophisticated as a single *protein* are something like one in four with a whole helluva lotta zeros after it. To illustrate those numbers, physicists will tell you that it's safer to bet on a tornado passing through a junkyard and accidentally putting together a fully functioning Boeing 747. Or blowing up a stack of bricks and timber and ending up with a Victorian townhouse.

And that's just for a protein, which is a far cry from a living being. The odds of idiot atoms getting together to create something living, i.e., something that can replicate itself efficiently, organize information, adapt, etc., are substantially smaller, still *trivially* small even relative to the number of stars we know about and the number of planets that might conceivably be orbiting them.

Life might very well exist elsewhere, but the odds are stacked a googolplex to one against. The odds of it happening twice in the same galaxy, let alone the same solar system, let alone a neighboring planet, are unthinkably small. The fact that we're alive doesn't necessarily mean that it can happen anywhere. If that happy accident hadn't happened, then we wouldn't be here to talk about it in the first place. (To say that something happens all the time because it happened once is a logical fallacy, so please don't come back at me with "but we're here.")

A great many people believe that all you need for life is a little water, a little dirt and some relatively mild temperatures. It just doesn't work that way, *unless* (and it certainly is possible, but would require an enormous leap of faith) there is a law that we don't yet know about that mandates life.

And since Mars and Earth share so much cosmological debris with one another, the odds are much more in favor of interplanetary migration than in independent spontaneous generation. If we do ever find evidence of life on Mars and can establish that it shares absolutely nothing in common with terrestrian biology (a truly herculean task, given the diversity of biological organisms on earth itself), that *would* be truly stunning.

I've argued this imperfectly. If you really want to learn about these things, check out "Are We Alone?" and "The Fifth Miracle" by Paul Davies.

[ January 29, 2004, 15:31: Message edited by: Gonzago ]

The fact that we have a very hazy perception of how in fact life began on this planet makes it very very very difficult to argue this point strongly either way.

But the big question that would swing the odds away from the 'googolplex to one' realms would be: are there any intermediate steps between an 'atom' and a 'protein'? If there was, and that intermediate step was a stable structure, you then take away the requirement for millions of atoms to crash together in exactly the right way.

It's still a long shot, but maybe it's more like putting together just one wheel (at first) out of our 'junkyard tornado' rather than the whole 747.

The fact that we have a very hazy perception of how in fact life began on this planet makes it very very very difficult to argue this point strongly either way.
True, but outside the point. We don't even know that life in fact began on this planet at all.

But the big question that would swing the odds away from the 'googolplex to one' realms would be: are there any intermediate steps between an 'atom' and a 'protein'? If there was, and that intermediate step was a stable structure, you then take away the requirement for millions of atoms to crash together in exactly the right way.
Even if there were something between an atom and a protein (a molecule, for instance) that were a stepping stone on the way to a truly living thing, it would still presumably have an expiry date (I almost wrote 'life span'), and without the ability to reproduce I don't see how that'd be viable. And the margin between atom and protein is a helluva lot smaller than the margin between protein and life.

I'm leaving for the weekend, so won't be able to answer this anymore 'til monday...

Why can't they just stick a camcorder on board and have it make a little Mars movie ;z

hey you never took into account the fact that we used to be rules by aliens and travelled through wormholes generated by "Star Gates" and thus there is millions of examples of life throughout the universe ;)