Scientists leading the Cassini-Huygen's mission to Saturn and its moons have released new pictures which show vast dunes of shifting hydrocarbon sand on Titan's surface.
Professor Philippe Paillou, a planetologist at the University of Bordeaux, and his colleagues compared images of the hydrocarbon dunes with sand dunes in the Namib Desert in Namibia and the Great Sand Sea in western Egypt.
Writing in a paper published on the open source website
arxiv.org, the team said: 'It appears that we can discriminate between two types of dunes - bare interdunes as in Egypt and sand-covered interdunes as in Namibia, and between two types of mega-yardangs - young yardangs as in Iran and older ones as in Chad.
'We applied our understanding of the radar scattering to the analysis of Cassini Radar T8 acquisitions over the Belet Sand Sea on Titan, and show that the linear dunes encountered there are likely to be of both Egyptian and Namibian type.
'We also show that the radar-bright linear features observed in Cassini Radar T64 and T83 acquisitions are very likely to be mega-yardangs, possible remnants of ancient lake basins at mid-latitude, formed when Titans climate was different.'
Titan, which has a diameter of 3,200 miles (5,150km), is the solar system's second largest moon and is larger than the planet Mercury.
It receives just one per cent of the sunlight that Earth does, however, meaning temperatures on the surface are an average of −290 °F (-179 °C).
Its atmosphere is known to comprise mainly of nitrogen and methane while the surface is made from frozen water that has turned into rock hard ice in the frigid tempeartures.
Titan is being revealed as a harsh and inhospitable place but despite having a toxic atmosphere of methane and nitrogen and freezing temperatures, it is also remarkably Earth-like
A dark H-shaped region around Titan's equator (pictured) has been shown to contain enormous dunes made of frozen methane sand, which scientists say are the remains of enormous methane lakes that have since evaporated. It suggests the distant moon was once a much colder place and has undergone climate change
The dark, H-shaped area seen around Titan's equator (pictured) contains two dune filled regions - Fensal in the north and Aztlan to the south. Researchers have used the Cassini spacecraft to study in in greater detail and compared it to dunes found in deserts on Earth.
French researchers compared Titan's dunes with four different types of sand dunes found in the Great Sand Sea in Egypt (a), the Namib Desert in Namibia (b) the mega-yardangs of the Lut Desert in Iran (c) and the Borkou Desert in Chad (d). The dunes on Saturn's moon were more similar to the first two
Images of Titan's surface sent back by the Cassini spacecraft have revealed large areas around the equator of the moon that are covered in linear dunes that are thousands of miles long (pictured)
TITAN: EARTH'S TOXIC TWIN?
Aside from Earth, Titan is the only place in the solar system known to have rivers, rainfall and seas - and possibly even waterfalls.
Of course, in the case of Titan these are liquid methane rather than water on Earth.
Regular Earth-water, H2O, would be frozen solid on Titan where the surface temperature is -180°C (-292°F).
With its thick atmosphere and organic-rich chemistry, Titan resembles a frozen version of Earth several billion years ago, before life began pumping oxygen into our atmosphere.
Because Titan is smaller than Earth, its gravity does not hold onto its gaseous envelope as tightly, so the atmosphere extends 370 miles (595km) into space.
As on Earth, the climate is driven mostly by changes in the amount of sunlight that comes with the seasons, although the seasons on Titan are about seven Earth years long.
With Titan's low gravity and dense atmosphere, methane raindrops could grow twice as large as Earth's raindrops.
As well as this, they would fall more slowly, drifting down like snowflakes.
Saturn's moon has also been found to be have a 'polar wind' in its atmosphere mimicking a process on our planet.
https://en.wikipedia.org/wiki/Titan_(moon)