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Titan's Tropical Weather
Hugh Pickens writes "Climate researchers Ray Pierrehumbert and Jonathan Mitchell at the University of Chicago say that Titan, the only moon in the solar system large enough to support an atmosphere, has many of the same weather features as Earth, but with completely different substances that work at temperatures that plunge down to minus 170 degrees Celsius. Pierrehumbert and Mitchell call Titan's climate 'tropical,' a climate that is warm to hot and wet year-round, because on Titan methane assumes the role of water and exists in enough abundance to condense into rain and form puddles on the surface. Titan's tropical nature means that scientists can observe the behavior of its clouds using theories they've developed to understand Earth's tropics. For example, Titan's atmosphere produces an updraft where surface winds converge to lift evaporated methane up to cooler temperatures and lower pressures, where much of it condenses and forms clouds, 'a well-known feature on Earth called an ITCZ, the inter-tropical convergence zone,' Mitchell says."
Har har, but no, it wouldn't. Methane is odorless. That's why gas companies have to include additives with natural gas, so leaks can be detected.
The Gish Bar Times - Blog covering Jupiter's moon Io
Methane, while produced in the gut of most animals, is odorless. The smell of flatus, to which you seam to be alluding, is mostly due to sulfur-containing compounds: Hydrogen Sulfide (in the case of the notorious "egg farts"), and various mercaptans, IIRC.
You could've hired me.
Dominant Meme
It is nice to see a climate model that adds in the information we have gleaned from the equatorial deserts on Titan. Much of the equatorial dark terrain on Titan is covered in sand dunes (made of organics, rather than quartz sand) while the bright material near the equator looks very much like the desert US southwest, with large mesas carved by the action of flowing methane, suggestive of short-duration, but high-volume, rain showers at equatorial latitudes. Much of the climate studies done recently have focused on the weather at the poles, were the majority of large clouds systems, lakes, and seas have been observed.
The Gish Bar Times - Blog covering Jupiter's moon Io
I'd say the biggest factor in determining if it's habitable is going to be its orbit and period, because if it's way off from our 24-hour day or 365~ day year, people would have a harder time adjusting than if it were simply lower gravity or hot or cold.
Titan does not really have "days" because its thick atmosphere spreads the warmth fairly equally to the day and night side. Besides, Titan is too cold for Humans. It is interesting in that it is doing on the methane level what Earth does on the water level. It's like a parallel universe where the water is instead methane. However, we humans are not compatible with that one. The "problem" is roughly comparable to an antimatter universe working like the matter universe (weather, rocks, etc.), but an antimatter being can't just move to the matter version as is.
Table-ized A.I.
Fortunately for most of us, the clock on our desktops are the only way we're keeping track of time. (It's always dark in the basement you know)
IMHO, Planetary time (or moon time, etc) is the least of our concerns when considering a habitable planet.
I think the GP concern of "days" is the length of when you have light, not temperature. I don't think it's that much of a concern though because there would be so much less light anyway. I think the "nights" where Titan is closer to the Sun might even be brighter than "days" because you get the diffuse reflection of sunlight off of Saturn. The times where the moon is behind Saturn are going to be extremely dark though.
Starting with the definition of Life as a process, I wonder if on Titan are the chemicals that exist there capable of encoding information such as the chemicals in DNA here on Earth? Life as we know it works with water and carbon as it's base substrates but these are not the only substrates a process that encodes structures that reproduce is limited to.
Shh.
http://en.wikipedia.org/wiki/Titan_(Stephen_Baxter)
enjoy.
How we know is more important than what we know.
I'm not a biochemist, but life does not depend only on water and carbon. IIRC, the most abundant elements in living matter are the "CHONPS" group: carbon, hydrogen, oxygen, nitrogen, phosphor, and sulfur. Although living cells are *mostly* carbon, hydrogen, and oxygen, several other elements are indispensable to life.
I'm rather skeptic of finding life on Titan, because lower temperature means less energy, which means less chemical reactions happening. Less reactions means less probability of hitting on the right combination needed to get a self-reproducing molecule.
I'd have to disagree -- people live in different areas of the earth where days are of vastly different lengths. And while it's not super healthy, many people live on all manner of strange day cycles with artificial light. I have read that without any clues as to time, people don't naturally settle into a 24 hour day anyways, and that in fact they vary their sleeping cycles longer and shorter over time.
:)
On the other hand, low gravity wreaks havoc with bones and blood vessel walls and such. Hot and cold we can control pretty well, so that's not a huge concern, though it certainly makes it more expensive. Radiation and such may also be a concern for planets without a strong magnetic field. And then there's the whole sustainable artificial ecosystem thing we've yet to work out to any real degree
Overall I think living on another planet is going to be a lot harder than we generally expect. We take for granted how well adapted we are to the specifics of planet Earth, and how much we depend on millions of other things that are also well adapted for the specifics of planet Earth. As someone suggested: it would be much easier to build a colony on the bottom of Earth's ocean than another planet, but we haven't even done that yet because it's cost prohibitive and the benefits aren't clear.
But we'll get there someday, I suppose!
Cheers.
Worked for me.. Stupid grizzly bears..
Control is an illusion, order our comforting lie. From chaos, through chaos, into chaos we fly
Something about that comment being modded "insightful" vs "funny" scares me.
Faster! Faster! Faster would be better!
Instead of curing us with prayer, doctors kill our precious children by refusing to prescribe antibiotics.
Speaking as a doctor I would appreciate if you could provide proof of this claim (other than the ramblings of a lunatic). Considering the continuing increased life expectancy of humans in the developed world, and the decreased infant mortality rates prevalent over the past and this century, I'd say that medical science has a fair grasp of what it's doing. Although it's hard to pair statistics to an individual person, as tools for determining trends in populations they are pretty darned useful and truthful.
Your comment is a perfect example of why YOU are not allowed to prescribe antibiotics.
Seven puppies were harmed during the making of this post.
Well its about twice as cold as the coldest place on Earth. But thats better as being twice as hot. Cold is much easier to engineer around.
With all that Methane in the atmosphere I wonder if you could get a modern vehicle using an internal combustion engine to work on the surface of Titan. Just put liquid oxygen in the fuel tank and feed it in through the fuel injection system.
http://michaelsmith.id.au
Valuable enough to offset the cost of transporting it from Titan? I really can't think of any substance that's that expensive. Well, maybe inkjet ink.
Speaking as a doctor...
Ehh, what's up, doc?
What?
No its not. In all places except the equator the length of sunlight changes slightly every day. The arctic and antarctic circles describe the latitudes at which the sun actually doesn't set one day per year.
If you go north of the arctic circle (or south of the antarctic circle) the effect gets greater and greater. This doesn't make them uninhabitable areas but it does mean that you can have weeks without a sunset (or a sunrise in the winter). A good example is Tromsø in north Norway. Its a fairly significant place, with a population of 60,000+ and a university. Yet they get a month of sunshine (and the same of darkness) every year - see http://www.gaisma.com/en/location/tromso.html. And Tromsø isn't even all that far north.
Hell, even where i am (a couple of hundred km short of the arctic circle) it doesn't really get dark during the summer. The sun "sets", but it only just dips below the horizon and so the twilight is extremely bright. Indeed, it can be brighter at 1am on a clear night than at midday with heavy clouds.
In any case, not only is Titan not alone, it's not the "only moon large enough..." Ganymede at Jupiter is actually larger than Titan, both in radius and (especially) in mass. If it were only a matter of size, Ganymede would have a thicker atmosphere than Titan. Heck, Titan's surface pressure is 1.5 times that of Earth, so clearly size isn't the only issue.
Sorry for the interruption, please carry on.