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: NASA's Webb Telescope mirror tripod in action (Video)

add to favorites email to friend print save as pdf

Related Stories

Titan offers clues to atmospheres of hazy planets

Jul 28, 2014

When hazy planets pass across the face of their star, a curious thing happens. Astronomers are not able to see any changes in the range of light coming from the star and planet system.

Recommended for you

NASA's Webb Telescope mirror tripod in action (Video)

2 hours ago

Setting up NASA's James Webb Space Telescope's secondary mirror in space will require special arms that resemble a tripod. NASA recently demonstrated that test in a NASA cleanroom and it was documented in ...

Iridium flares captured in real time by astrophotographer

10 hours ago

There are so many fun sights to see in the sky that are pure astronomical magic. And then there are the spectacular human-created sights. One of those sights is watching satellites from the Iridium constellation ...

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.