I’m looking for the images transmitted to include some of a big, unhappy-looking purple guy in a blue jumpsuit…
I don’t think that anyone is expecting swaying vegetation. Even if there is some spot somewhere that gets transiently warm enough on rare occasion to harbor some sort of “seasonal”* life, it would be improbable that we’d find it. It is hard enough to find life at the extreme in earthly settings. Life would have to quite a bit denser than even most xenobiologist** optimists expect it to be for us to hit a jackpot here. It will be interesting enough to see if the building blocks are there and how much of them. But neither would I rule out the possibility just because the environment is extreme by terrestial lifeform standards.
*And “seasons” may be a global warming that occurs once every hundred thousand or so years for all we know …
**Is “xenobiology” or “astrobiology” the preferred word?
Astrobiology I guess.
Yeah, well, you know what really happened there, don’t you?
“What’s the matter, General? They’ve sent these things before . . .”
“But this one is about to get pictures of the invasion fleet! ZAP IT! ZAP IT!”
DSeid, thanx for the info on microbial life in Antarctica. I never knew that. It gives me hope that life might be found elsewhere in the solar system.
But is the Cassini probe equipped to detect microbes, if they’re there?
Here is another yahoo story with a cool slideshow including some Titan pics.
Is there any evidence of volcanism on Titan? I would think that Saturn might squeeze it enough to heat it up (a la the Jovian moons), and if so, you’ve got your heat source for your microbes (like the thermal vents at the bottom of our own seas).
Europa orbits Jupiter at 670,000 km. Titan is out at 1,200,000 km. There’ll be much less tidal heating there.
This is as good a pre-Cassini mission summary of what we know about Titan as you will find.
Here’s JPL’s Saturn research homepage , which includes details of the instruments aboard the Huygens probe for those who wish to know what the probe will be doing.
(Person formerly responsible for researching and creating educational presentations on NASA/JPL missions here)
this mission is an Orbiter mission.
The JPL, whose current expressed reason for existence is the robotic exploration of the Solar System, explores planets in stages:
Stage I: Flyby
A spacecraft is sent on a close rendezvous with the planet, taking picures and gathering whatever data it can in other forms on its way past. In Saturn’s case, the flybys were Pioneer 10, Voyager I and Voyager II. The data collected from them in the late 1970s was used to develop
Stage II: Orbiter
A planet-specific mission is sent to spend a long time around the planet, building on whatever was found during flyby. Galileo recently finished a similar mission to Jupiter, and Cassini-Huygens has just begun doing the same for Saturn. You can’t land on Saturn, but the moons are good targets, so data from this will be used to develop
Stage III: Lander
Once the orbiter gives us data about the surface, we can develop a lander that is designed to explore that surface. The JPL has only done lander missions to the Moon and Mars. The Russians sent one to Venus. Huygens is not really a lander, because it isn’t designed to take advantage of Titan’s surface features in its mission. Its mission is to determine what those surface features are for future landers. A real Titan lander is something we might see in the future. If some material deserves more investigation than a lander/probe can carry out, we may see a
Stage IV: Sample-Return
Here, material is launched from the planet back here for close-up study. We have only done sample-return missions to the Moon. One of JPL’s least-publicized recent missions, Stardust, collected samples from Comet Wild-2 this past January after 5 years in space (and collected interplanetary dust samples on the way), but its trajectory will not bring the samples back for another year and a half. We might see a sample-return mission to Mars in the next 10-15 years.
A bump, but I think a fair one.
Do we know anything new now that encourages or discourages the belief that life on Titan can exist?
Could there be microorganisms lurking in the photographs we’ve seen? (Thus far, there have been no pictures of visible plant life, etc.).
Your opinions, please!
Well we now know that the environment’s not static. Methane undergoes phase changes. Photochemical smog from the atmosphere precipitates, and gets concentrated in runoff channels. What liquid there is likely qualifies as a concentrated organic soup. There’s no glaringly obvious energy gradient for life to exploit, and even if there were, any life would have to have a vastly different chemistry than that on earth. Huygens certainly didn’t rule out life on Titan, but it didn’t give us any obvious signs of biology in action either.
How do you define life?
Hate to say it but it looks bad.
It looked like Mars but with smog.
It was still cool, but I was hoping for…
Well, terrain.
Did you somehow miss those beautiful drainage channels and methane springs? Just look at how the dark smog particles are concentrated near the bottom of the channels. That’s interesting terrain!
This argument has burbled for years. Some people are intent on believing that life is very rare, very fragile, can only occur under just the right conditions, and that those conditions are extremely narrow and fickle. Myself, I’ve always tended to the opposite view, that life abounds, that it happens wherever and whenever any chance, however small, permits. I freely admit that those views are based largely on my biases and prejudices.
But the evidence that most strongly supports my view isn’t on Titan, they are at the bottom of our very own oceans, where microbes exist where they have no right to exist, in temperatures that should annihilate them, subsisting on corrosive toxins that should kill them. At pressures that should make them impossible.
And yet, there they are. And for reasons I don’t begin to understand, such impossible life is an epiphany. The very skies whisper: “I am”. And I smile.
[john stewart]
It just reaches out to bore you!
[/john stewart]
I would wager more for Europa.
Speaking more generally, the fact that there is liquid methane along with phase-changes is very encouraging. Water’s advantage for life isn’t simply in it’s hospitability to organic compounds, but also in simply providing an active medium. I wonder: how much Brownian motion is there in liquid methane at those temps.
But I do have to say that the cold seems like a pretty bad deal for life. There’s just not enough going ON for it to be much more than relatively static. Titan is probably the closest we have in the solar system to a complete body that’s at least physically similar to earth, but the chemistry isn’t quite right and the whole thing is in slow-mo.
Europa is more interesting not only because the evidence of possible volcanic activity under it’s cracky ice-shell means that there could be plenty of spaces that are liquid and stay liquid. Unfortunately, the ice likely blocks out a lot of the UV rays and other such events that likely spurred things on on earth.
Developing what Apos said, I wonder how efficient a solvent liquid methane is. If it’s a good solvent then perhaps it can act as a host for biochemical reactions much as water does.
And how come the surface of Titan is yellow? Doesn’t that mean sulphur and vulcanism?