Titan's surface organics surpass oil reserves on Earth

February 13, 2008
Titan's surface organics surpass oil reserves on Earth
An artist's imagination of hydrocarbon pools, icy and rocky terrain on the surface of Saturn's largest moon Titan. Credits: Steven Hobbs

Saturn’s orange moon Titan has hundreds of times more liquid hydrocarbons than all the known oil and natural gas reserves on Earth, according to new Cassini data. The hydrocarbons rain from the sky, collecting in vast deposits that form lakes and dunes.

The new findings from the study led by Ralph Lorenz, Cassini radar team member from the Johns Hopkins University Applied Physics Laboratory, USA, are reported in the 29 January 2008 issue of the Geophysical Research Letters.

"Titan is just covered in carbon-bearing material—it’s a giant factory of organic chemicals," said Lorenz. “This vast carbon inventory is an important window into the geology and climate history of Titan.”

At a balmy minus 179º C , Titan is a far cry from Earth. Instead of water, liquid hydrocarbons in the form of methane and ethane are present on the moon's surface, and tholins probably make up its dunes. The term ‘tholins’ was coined by Carl Sagan in 1979 to describe the complex organic molecules at the heart of prebiotic chemistry.

Cassini has mapped about 20% of Titan's surface with radar. Several hundred lakes and seas have been observed, with each of several dozen estimated to contain more hydrocarbon liquid than Earth's oil and gas reserves. The dark dunes that run along the equator contain a volume of organics several hundred times larger than Earth's coal reserves.

Proven reserves of natural gas on Earth total 130 thousand million tons, enough to provide 300 times the amount of energy the entire United States uses annually for residential heating, cooling and lighting. Dozens of Titan's lakes individually have the equivalent of at least this much energy in the form of methane and ethane.

"This global estimate is based mostly on views of the lakes in the northern polar regions. We have assumed the south might be similar, but we really don’t yet know how much liquid is there," said Lorenz. Cassini's radar has observed the south polar region only once, and only two small lakes were visible. Future observations of that area are planned during Cassini’s proposed extended mission.

Scientists estimated Titan's lake depth by making some general assumptions based on lakes on Earth. They took the average area and depth of lakes on Earth, taking into account the nearby surroundings, like mountains. On Earth, the lake depth is often 10 times less than the height of nearby terrain.

"We also know that some lakes are more than 10 m or so deep because they appear literally pitch-black to the radar. If they were shallow we'd see the bottom, and we don't," said Lorenz.

The question of how much liquid is on the surface is an important one because methane is a strong greenhouse gas on Titan as well as on Earth, but there is much more of it on Titan. If all the observed liquid on Titan is methane, it would only last a few million years, because as methane escapes into Titan's atmosphere, it breaks down and escapes into space. If the methane were to run out, Titan could become much colder. Scientists believe that methane might be supplied to the atmosphere by venting from the interior in cryovolcanic eruptions. If so, the amount of methane, and the temperature on Titan, may have fluctuated dramatically in Titan’s past.

“We are carbon-based life, and understanding how far along the chain of complexity towards life that chemistry can go in an environment like Titan will be important in understanding the origins of life throughout the universe,” added Lorenz.

Cassini's next radar flyby of Titan is on 22 February 2008, when the radar instrument will observe the landing site of ESA’s Huygens probe.

Source: ESA


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3 / 5 (3) Feb 13, 2008
that's funny because nasa just announed it was seeling corporate naming rights to exxon for its next mission to titan.
1.7 / 5 (6) Feb 13, 2008
Space? We don't need to go out to space, its just a big waste of time...and money. Nothing comes of it anyways, there is nothing out there, everything we need is here. We should stop building telescopes and use that money to grow more corn to make more fuel for our SUVs instead! Besides I would much rather sit back and watch the Chinese get there first...of course I am being sarcastic, but who cares these days anyways.
2 / 5 (4) Feb 13, 2008
That whole 'space' thing is a hoax!
5 / 5 (5) Feb 13, 2008
If you thought gas prices are high now, wait till they start importing it form Titan!
3.7 / 5 (3) Feb 14, 2008
Makes a rethink for Thomas Gold's book on the inorganic origin of hydrocarbons.
3.7 / 5 (3) Feb 14, 2008
That gives much more credit to the primordial soup idea.
1 / 5 (1) Feb 14, 2008
that's funny because nasa just announed it was seeling corporate naming rights to exxon for its next mission to titan.

now that'd be a brilliant plan.. lets bring more carbon into our bio-dome we call earth...
not rated yet Feb 14, 2008
Now all we need to do is get behind a propulsion technology that will take us there. Here is one I ran across just published.


Mover over Saudis ! America takes the lead !
not rated yet Feb 14, 2008
that's funny because nasa just announed it was seeling corporate naming rights to exxon for its next mission to titan.

now that'd be a brilliant plan.. lets bring more carbon into our bio-dome we call earth...

So, I see your understanding of geometry is on par with your understanding of climate change. dome dome = sphere. Just sayin'...
1 / 5 (1) Feb 14, 2008
the moon landing was a hoax! Global warming is scary too (I'm being sarcastic ;)
1 / 5 (2) Feb 14, 2008
Its so funny that all of the science taskers talk about carbon and dont consider the root and origin of that word,why dont you try heat bonded carbohydrate for a bit and see where that goes for ya. For there to be natural gas/methane,there has to be plant growth at some point that created the biomass to be depleted into that gas,wouldnt you think?? All of the ol on the earth was created by a system explosion 28 thousand years ago that revved the grid field so much that the planet cooked all of the living plants down to a slurry that ran into the pockets created by the water exploding pockets from the heated magma,this system explosions remnants also returned on that elliptic oxygen line that it travels on 14 thousand years ago and created the sweet crude on the planet.So put those factual tidbits into your goofy computer modeling paradigm boys. More to come in other commentary terrorism for you puffed up theoreticians
2 / 5 (1) Feb 15, 2008
oh, great all we need. a no bid, cost plus contract for a pipe line
for halliburton
not rated yet Aug 06, 2009
That whole 'space' thing is a hoax!

Ummm...No. It isn't. Of course, I think you were being sarcastic.

Anyone who actually has been out there knows it's not a hoax. Come to think of it, if you can raise a few hundred thousand dollars you, too, can be launched into space for a little while.

Or, you can pay some cash and try to get on a Russian rocket and visit ISS. That could be fun, too.

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