Titan's Dunes Took Tens of Thousands of Years To Form

sciencehabit writes: Massive dunes, some of them 100 meters tall and a kilometer or more wide at their base, cover about one-eighth of Titan's surface. And they take an exceptionally long time to form, according to a new study. Using radar data gleaned by the Cassini probe when it occasionally swooped past Saturn's haze-shrouded moon, researchers conclude that it would take about 3000 Saturn years (or 88,200 Earth years) to shift Titan's dunes to the extent seen in the images. A similar phenomenon has taken place on Earth, the researchers note: The overall patterns in many large dune fields in the southwestern Sahara and the southwestern United States, shaped by the winds that blew during the most recent ice age more than 10,000 years ago, remain largely unaffected by modern winds that now blow in a different direction.

Comments

WRONG!

[Anonymous Coward]

It took muuch less!

Not too bad

[pushing-robot]

Still ahead of Jodorowsky's Dune.

Re:Not too bad

[FilmedInNoir]

If all we had was millions of people with shovels it would be cheaper to produce as well.

Danger: Mobile Sand Dunes On Road

[Anonymous Coward]

I live in the desert and have observed fast moving dunes and static dunes. Both types have lots of sand blowing about, but somehow the static dunes stay where they are. The static dunes are irregular shaped (star dunes) and can have big trees growing on or around them and the trees do not get covered by the sand. Barcan (crescent) dunes are strange in that they litterally crawl accross a plain. There can be sand/gravel, trees, bushes and rocks in front and behind them, but if one look closely over time, they move meters per month.

Re:Danger: Mobile Sand Dunes On Road

[Anonymous Coward]

thats what I found very fascinating when I first heard of this research. You can infer many things about the environement just by looking at the dunes (which you can do from space).

monochromatized population unmotivated?

[Anonymous Coward]

spiritually bankrupt due to dark deception & fake history & heritage addiction 1000 years (++) of damp grayness continues ... check us out http://www.youtube.com/results?search_query=truth+about+US

hmmm

[rmdingler]

I'm sure these estimates are based on available data and proffered by folks more qualified than I to render them.

But. We have only a limited understanding of conditions on a world like Saturn, and extrapolating from a small pool of data is often inaccurate.

Remember how the Mars rovers' lifespan was greatly underestimated? It was believed the sand would eventually collect on the solar power arrays due to the planet's winds. As it happened, the winds actually helped keep them clear.

Re:hmmm

[ubergeek09]

You're angry that science reporters are doing science reporting. This is the analysis of the data that has been collected thus far and it is the most reasonable explanation.

Re:hmmm

[TWX]

The rovers' lifespans were only 'warrantied' to 90 Sols, not simply expected to fail after 90 Sols.

This is a guess, but they probably based the solar panel situation on landers' results, which did end up being blocked by dust. Perhaps the landers generally ended up in places where natrual accumulation is worse, or perhaps the act of the rovers turning to different orientations relative to the prevailing winds has made built-up dust easier to shed. Either way, being pessimistic about the performance of one's platform is usually better than being optimistic about it and then being let-down. Look at Curiosity's wheels for an example of that.

That's nothing

[Anonymous Coward]

90,000 years is not an "exceptionally long time" when dealing with planetary processes. Not by a long shot.

Re:That's nothing

[Anonymous Coward]

90,000 years is not an "exceptionally long time" when dealing with planetary processes. Not by a long shot.

That would depend on the process in question, now wouldn't it? Thunderstorms are a "planetary process". Ever seen one last 90,000 years?

Given how fast dunes can move, 90,000 years IS an "exceptionally long time".

Re:That's nothing

[Anonymous Coward]

As a planetary scientist, but mostly working on atmospheres, I have to disagree. This is a very short time for _geological_ processes, but a very long time for processes involving structures of a matter so fine grained that it is easily moved around by wind (sand or with grain size comparable to sand).
At the surface level, the density in molecules per cubic meter of Titan's atmosphere is ~5 times the Earth's atmosphere at sea level, so it does not take much wind (fluid velocity) to move around small grains provided they are not stuck together by some other agent (water on Earth, liquid hydrocarbons on Titan).