NASA’s Cassini spacecraft is monitoring the evolution of a mysterious feature in a large hydrocarbon sea on Saturn’s moon Titan. The feature covers an area of about 100 square miles (260 square kilometers) in Ligeia Mare, one of the largest seas on Titan. It has now been observed twice by Cassini’s radar experiment, but its appearance changed between the two apparitions.
The mysterious feature, which appears bright in radar images against the dark background of the liquid sea, was first spotted during Cassini’s July 2013 Titan flyby.
Previous observations showed no sign of bright features in that part of Ligeia Mare. Scientists were perplexed to find the feature had vanished when they looked again, over several months, with low-resolution radar and Cassini’s infrared imager. This led some team members to suggest it might have been a transient feature. But during Cassini’s flyby on August 21, 2014, the feature was again visible, and its appearance had changed during the 11 months since it was last seen. Continue reading follow article link