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Lake On Titan Winks From a Billion Kilometers Away
The Bad Astronomer writes "NASA's Cassini spacecraft took an image of Saturn's giant moon Titan earlier this year that serendipitously provides proof of liquid (probably methane) on its surface. The picture shows a glint of reflected sunlight off of a monster lake called Kraken Mare (larger than the Caspian Sea!). Scientists have been getting better and better evidence of liquid methane on Titan, but this is the first direct proof."
Its called a terameter. What is the point of the metric system if you don't use the other scales?
lol: You see no door there!
Prior to this, the main evidence that Titan might have liquid methane was based on the reflection of radio waves detected by the Cassini probe. In particular, there were discrepancies between what one would expect and what was observed in the percentage of reflection in the ELF range (about 2 to 30 Hz). This discrepancy suggests some form of boundary layer, such as a boundary between liquid and solid methane or between liquid methane and some other solid substance. There's also a lot of evidence for a large internal methane sea under the solid surface. We still know very little about Titan. We've only sent a single probe (Huygens) actually dedicated to investigating it. However, even Huygens wasn't much and was just a part of the larger Cassini mission. The next scheduled mission is the TSSM (Titan Saturn System Mission) (http://en.wikipedia.org/wiki/Titan_Saturn_System_Mission http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=44033) which will focus a lot more on Titan. Hopefully a lot of the mysteries about the moon will then be answered.
Titan is routinely used as an example of a moon that might have life. Unfortunately, if there is any life, it is almost certainly microbial. So no one is appreciating the view from the planet.
We know that Titan has a lot of methane. The main reason is that the radiation it gives off is consistent with methane. In particular, we can use spectroscopy to confirm that the light given off is highly consistent with methane reflecting light from the sun. See http://en.wikipedia.org/wiki/Spectroscopy. We have evidence for the methane nature both in the visible range, infrared range and certain other ranges that is consistent with methane and not much else. Moreover, methane is very stable and fairly common (as chemicals go) so even if we didn't have very good spectroscopic data, it would be the most likely guess.
This image was taken by Cassini, the US probe currently orbiting Saturn. http://www.nasa.gov/mission_pages/cassini/multimedia/cassini20091217.html Issues in our own atmosphere thus could not impact this. And if you meant that Titan might have strange atmospheric behavior causing this, that's almost as unlikely. The size of this event is much larger than almost any weird atmospheric event (which are normally at most a few hundred meters large at the very largest, rather than many kilometers across. Moreover, this picture isn't the only data point. The data was consistent with specular reflection over all observed wavelengths (both visual and near infrared). So you would need to posit an extremely large event that happened to precisely duplicate what we'd expect to see in reflection. That's remotely possible, but not at all likely. There's never "proof" in science. Proof is for mathematics and alcohol. But this is very strong evidence for the presence of a large body of liquid methane on the surface of Titan.
ALL THESE FARTS ARE YOURS. USE THEM WISELY, AND DON'T LIGHT ANY NAKED FLAMES.
EXCEPT TITAN. ATTEMPT NO LANDING THERE, BECAUSE IT BLOODY STINKS.
Filter error: Don't use so many caps. It's like YELLING. Yes, right, I'm sure Stanley Kubrick told Arthur C. Clarke the same thing when they were finalizing the screenplay. So now I'm reduced to typing a lot of mindless garbage just to get around the lousy Slashdot filter.
Methane is the precursor to organic molecules, in a more general sense, not the result of biological processes. When you're the simplest combination of carbon (what, the fourth most abundant element in the universe?) and hydrogen (the most abundant element), it's hard to argue that your existence requires biological processes. (Particularly as methane is found everywhere volatiles can be found in our solar system and outside of it.)
Perhaps you're confused by the fact that methane on Earth is usually the result of biological activity? That's because in our peculiar atmosphere, methane can't survive long before oxidation.
The methane is believed to come from geological processes and not from life.
Methane is an organic material. Organics are one of the key building blocks of life. In fact, it is one of many byproducts of life processes. An abundance of organic material bodes well for finding life (probably bacterial) on Titan.
I doubt it. "Organic" is an artificially created classification. It just means anything that is prevalently composed of carbon atoms. There happen to be a lot of carbon atoms in the universe, due to its relatively low atomic mass. There's also a ton of helium. It is not really surprising that these common elements might be found, in combination, in large quantities. We have large deposits of hydrocarbon here on Earth as well. Yes, these compounds are, according to our own definitions, "organic", and in fact originated from living matter, but we do not see organisms thriving in the deep oil wells.
I do not see how an excess of methane would indicate the likelihood of finding "bacterial" life. What would the cell walls be composed of? It would have to be something like a lipid bi-layer, so that the membrane wouldn't just dissolve into the methane. But then, what's INSIDE the cell? Probably, it would be more hydrocarbons. These non-polar materials are ill-suited as stages for complex, biological chemical reactions. They cannot dissolve ions. Without soluble ions, hell, without soluble polar compounds, there isn't a whole hell of a lot of interesting chemistry that can take place.
If we found tons of water that would be far more indication of the potential for life. Water has dozens of extremely unusual properties all of which make it conducive to life.
Read the name of the "lake", - Kraken Mare.
It's just a big puddle of sea-monster piss, nothing exciting at all.
"I've got more toys than Teruhisa Kitahara."
We all know it's faked. Those slimy scientists will do anything to guarantee their funding for another year. Last year it was a decoupled lithosphere on Titan, now it's lakes of liquid hydrocarbons? Sure! Next it'll be seasonal rivers of liquid hydrocarbons, jets of water escaping from Enceladus, volcanism on Io, meteorites on Mars, people on the moon, etc., etc., etc. We really need to reign in these people.
The odds for life on Titan are bleak because it is so damned cold. How cold is Titan? Well, when your methane is liquid, as in, liquified natural gas, that's pretty damned cold. The other problem, I think, is a lack of oxygen. I think the basic blocks for life would be nitrogren, oxygen, hydrogen, carbon and I think a splash of sulfur, plus some form of energy. When you really think about it, life is basically a set of chemical reactions that go against the grain of entropy and produce a set of molecules that arrange things in a higher energy state. Like, the outcome of most dead things is to easily burn.
Mercury is big metal blob and way too hot.
Venus has too much carbon.
Earth is nice.
Mars is missing nitrogen.
Jupiter / Saturn / Uranus / Neptune big hydrogen blobs.
Pluto, other deep objects, are near absolute zero.
Maybe Jupiter's moon Europa might luck out.
But honestly, I would bet that if you included some terms in Drake's equation to allow for the probability of having all the elements in the right mix at the right distance from a star, then, it may well turn out that we are certainly alone in at least a 100 light year radius.
This is my sig.