Comments on: Lakes on Titan?

By: madjon

madjon — Mon, 30 Jul 2007 14:33:50 +0000

“It appears to me that these â€œlakesâ€ may actually be terrain, but with a lower radar-reflectivity than the surrounding. Possibly mud?”
The ‘rivers’ or flow features going into these depressions point strongly to a fluid entering them, however its by no means certain, given the zoo of organic chemicals they are likely to contain, that whats in the lakes is also liquid. The material in the lakes is likely to have any impurities or dissolved chemicals concentrated by evaporation; I think the term goo would apply very well to it.

By: JD

JD — Wed, 01 Nov 2006 04:08:58 +0000

“excremental so-and-sos”

such deep intellect you possess.

you have no clue how life arose.

none.

By: Mungascr

Mungascr — Sat, 02 Sep 2006 07:57:32 +0000

Mercury the Suns moon, Scott?!?
Ithink thatcould apply to all theplanets if its not what you call a planet full stop.

A planet goes round a star ie. our Sun, a moon goes round a planet -or insomecases an asteroid or planetoid.

I’d call Titan a world - or a large moon. In fact, it is the largest moon beating Ganymede and Callisto for that honour. Its nearly as big asMars and bigger than Mercury -and yes its a very cool place.

The finding of lakes may be old news now but its still marvellous.

As for Phil Plait helping creationists by his “no clue how life sparked” line those excremental so-and-sos would twistsanyone’s words given thechance -bestthingany of us can do is take whatever they say with a shaker-full of salt. In truth though, we _do_ have quite a few clues on how life started just no certainities. Which puts us a considerable few steps ahead of those who claim to know with utter certainty but resort to the “God said so” fallacy of authority as their only evidence.

By: Selden

Selden — Mon, 31 Jul 2006 20:51:24 +0000

I discovered that if you pull these images into Photoshop and stretch the contrast, the “lake” features contain terrain that resembles craters and rivers, similar to the surrounding terrain. It appears to me that these “lakes” may actually be terrain, but with a lower radar-reflectivity than the surrounding. Possibly mud?

See an example at http://www.smccabe.net/titan_lake1.jpg

By: George Greene

George Greene — Fri, 28 Jul 2006 19:05:55 +0000

So Titan has a temperature of 180 Celsius, huh? Amazing for a body so far from the sun. Even the earth has a mean surface temperature of only about 15 C.

By: Riofrio

Riofrio — Fri, 28 Jul 2006 04:18:46 +0000

Enceladus has a polar hot spot venting gas into Space, which might indicate subsurface water. Earth’s Antarctic has subsurface lakes which are considered likely homes for life. Note that all these bodies have “hot spots” located on their poles. Even Saturn herself has a polar hot spot visible at 17.65 microns; check out the photo. Makes you think, doesn’t it?

By: TheBlackCat

TheBlackCat — Fri, 28 Jul 2006 04:07:43 +0000

Scott says:

“5. Body with no atmosphere”

How do you define “atmosphere”? Even the moon has an ambient pressure higher than that in interplanetary space. And the entire solar system has a pressure higher than that of interstellar space, which has pressure higher than that of intergalactic space, and so on. You must set some sort of arbitrary cut-off in terms of ambient pressure in order to define “presence” or “absence” of an atmosphere. Also, how do you define a “climate”? Does Mars have a climate? It certainly has weather and changing local atmospheric conditions. But then again, so would any body with any gas at all, since the body would not be recieving uniform energy at all points. Even interplanetary space has “weather” from particles streaming away from the sun and the passage of bodies like comets.

“The probability of life on Titanâ€“and subsequent evolution that may have occurredâ€“pivots on the time frame in which Titan has maintained a climate near the state it is currently at or at a more life-friendly state (if there ever was one). The other main variable in the Titan-life equation would be how likely life came from outside the planet or was induced upon the planet (if that is at all possible under any conditions that ever existed on the planet).”

It also requires a chemical environment in which life can develop. This is not by no means given. Simply having a planet stable long enough will not allow life to develop if the local environment prohibits the evolution life. Simply having solid liquid and gas does not mean life can necessary develop in that solid, liquid, and gas. It doesn’t mean it can’t, either, but it is simply not a given.