Scientists analyzing data from NASA’s Cassini mission have firm evidence the ocean inside Saturn’s largest moon, Titan, might be as salty as Earth's Dead Sea.
The new results come from a study of gravity and topography data collected during Cassini’s repeated flybys of Titan during the past 10 years. Using that data, researchers presented a model structure for Titan that resulted in a better understanding of the moon’s outer ice shell. The findings are published in the June 30 edition of the journal Icarus.
Other findings support previous indications the moon’s icy shell is rigid and in the process of freezing solid. Researchers found a relatively high density was required for Titan’s ocean to explain the gravity data. This indicates the ocean is probably an extremely salty brine of water and dissolved salts likely composed of sulfur, sodium and potassium. This brine’s density would give the ocean a salt content roughly equal to that of Earth’s Dead Sea.
“This is an extremely salty ocean by Earth standards,” said the paper’s lead author, Giuseppe Mitri of the University of Nantes in France. “Knowing this may change the way we view this ocean as a possible abode for present-day life, but conditions might have been very different there in the past.”
Cassini data also indicate the thickness of Titan’s ice crust varies slightly from place to place. The researchers said this could mean the moon’s outer shell is stiff, as it would be if the ocean were slowly turning to ice. This freezing process would have important implications for the habitability of Titan’s ocean because it would limit the ability of materials to exchange between the surface and the ocean.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency.