Just How Significant Is Methane On Titan?

Sep 12, 2005

Titan's second most abundant constituent, methane, is critical to the maintenance of an earth-like nitrogen atmosphere on this satellite. Without methane, Titan's nitrogen would condense, leaving behind a puny amount in the atmosphere.

Source of Titan's methane

The Sun's ultraviolet light should have destroyed methane in approximately ten million years-a fraction of Titan's age. Some process must be producing methane lost to photolysis. Unlike the deep, dense atmospheres of the giant planets where the photoproducts of methane are cooked in their hydrogen-rich interiors to produce methane back, photoproducts of Titan's methane do not meet the same fate.

Hence, methane came in as methane clathrates during Titan's formation, or it is manufactured in situ in Titan's interior. Noble gas data tend to favor the latter process that is based on serpentinization.

I consider low temperature serpentinization as a very promising source of methane on Titan. It occurs in terrestrial oceans, e.g. in Lost City 15-20 km from spreading centers where Black Smokers are sighted.

The process involves water-rock reactions. The type of rocks and temperatures needed are expected to exist in Titan's interior also.

In this process, hydrogen (H2) is released in the hydration of iron or magnesium rich rocks (ultramafic silicates), and this H2 then combines with carbon dioxide or carbon in crustal pores to produce methane. Methane so produced could be "stored" as clathrate in Titan's interior for later release to the atmosphere, or the process could be going on even now.

Biology as a source of methane on Titan is not supported by the data.

Copyright 2005 by Space Daily, Distributed United Press International

Explore further: A curious family of giant exoplanets

Related Stories

Titan's atmosphere useful in study of hazy exoplanets

Apr 23, 2015

With more than a thousand confirmed planets outside of our solar system, astronomers are attempting to identify the atmospheres of these distant bodies to determine if they could possibly host life.

Why don't we search for different life?

Mar 03, 2015

If we really want to find life on other worlds, why do we keep looking for life based on carbon and water? Why don't we look for the stuff that's really different?

Recommended for you

Ceres bright spots sharpen but questions remain

32 minutes ago

The latest views of Ceres' enigmatic white spots are sharper and clearer, but it's obvious that Dawn will have to descend much lower before we'll see crucial details hidden in this overexposed splatter of ...

What are extrasolar planets?

42 minutes ago

For countless generations, human beings have looked out at the night sky and wondered if they were alone in the universe. With the discovery of other planets in our solar system, the true extent of the Milky ...

Rosetta's view of a comet's "great divide"

52 minutes ago

The latest image to be revealed of comet 67P/Churyumov-Gerasimenko comes from October 27, 2014, before the Philae lander even departed for its surface. Above we get a view of a dramatically-shadowed cliff ...

How long will our spacecraft survive?

1 hour ago

There are many hazards out there, eager to disrupt and dismantle the mighty machines we send out into space. How long can they survive to perform their important missions?

Why roundworms are ideal for space studies

1 hour ago

Humans have long been fascinated by the cosmos. Ancient cave paintings show that we've been thinking about space for much of the history of our species. The popularity of recent sci-fi movies suggest that ...

A curious family of giant exoplanets

1 hour ago

There are 565 exoplanets currently known that are as massive as Jupiter or bigger, about one third of the total known, confirmed exoplanet population. About one quarter of the massive population orbits very ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.