Changes in Titan's surface brightness point to cryovolcanism

September 14, 2013
Cryovolcanic candidate ‘Sotra Patera’ on Titan has a deep crater (1km) and a significantly high mountain. (Image credit: NASA/JPL Caltech/USGS/University of Arizona). The Kirishima volcano in Japan, a terrestrial analogue (Image credit: USGS).

Changes in surface brightness on Titan observed over four years by NASA's Cassini spacecraft have added to evidence that cryovolcanism is active on Saturn's largest Moon. Anezina Solomonidou has presented results at the European Planetary Science Congress (EPSC) 2013 in London. The authors compared many volcanic-like features, such as flows, calderas and craters, with similar geological features found on the Earth to study the possibility of cryovolcanic activity within regions observed close to Titan's equator.

Titan has an atmosphere rich in organic carbon-based compounds and astronomers believe that beneath its icy surface there is an ocean of liquid water, possibly mixed with ammonia. The low number of seen on Titan suggests that the surface is relatively young and is therefore dynamic and active. Titan has clouds and rains of that mimic Earth's water cycle. Its landscape is remarkably Earth-like with dunes and lakes, erosion due to weathering and tectonic-like features.

"All of these features, plus a need for a methane reservoir and volcanic activity to replenish the methane in the atmosphere, is compatible with the theory of active cryovolcanism on Titan," explained Solomonidou, of the Observatoire de Paris and National and Kapodistrian University of Athens.

Solomonidou and colleagues investigated the potentially cryogenic regions of Tui Regio, Hotei Regio and Sotra Patera using Cassini's Visual and Infrared Mapping Spectrometer (VIMS).

"We were able to penetrate the atmosphere with VIMS and view any changes in these surface features. Interestingly, the albedo (brightness) of two of the areas has changed with time," explained Solomonidou. "Tui Regio got darker from 2005 to 2009 and Sotra Patera—the most favourable cryovolcanic candidate on Titan—got brighter between 2005 and 2006."

Surface variations, together with spectral albedo properties and the presence of volcanic-like features, suggest that these cryovolcanic candidate regions are connected to Titan's deep liquid ocean.

"These results have important implications for Titan's potential to support life as these cryovolcanic areas might contain environments that could harbour conditions favourable for life," said Solomonidou.

Explore further: Beneath the mask, Titan looks surprisingly smooth and youthful

Related Stories

Titan's methane: Going, going, soon to be gone?

April 16, 2013

( —By tracking a part of the surface of Saturn's moon Titan over several years, NASA's Cassini mission has found a remarkable longevity to the hydrocarbon lakes on the moon's surface.

Mystery of the missing waves on Titan

July 23, 2013

One of the most shocking discoveries of the past 10 years is how much the landscape of Saturn's moon Titan resembles Earth. Like our own blue planet, the surface of Titan is dotted with lakes and seas; it has river channels, ...

Recommended for you

NEOWISE identifies greenhouse gases in comets

November 24, 2015

After its launch in 2009, NASA's NEOWISE spacecraft observed 163 comets during the WISE/NEOWISE prime mission. This sample from the space telescope represents the largest infrared survey of comets to date. Data from the survey ...

Cool, dim dwarf star is magnetic powerhouse

November 19, 2015

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered that a dim, cool dwarf star is generating a surprisingly powerful magnetic field, one that rivals the most intense magnetic regions ...


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.