NASA's Cassini spacecraft is monitoring the evolution of a strange object in a giant hydrocarbon sea located on Saturn's moon Titan.
The mysterious feature covers 100 square miles in Ligeia Mare, one of Titan's largest seas. The object appears bright against the dark background of the water.
The appearance of the object has changed twice in Cassini radar observations. It was first spotted in a July 2013 Titan flyby. Previous observations had not revealed the feature and scientists were shocked to see that it had disappeared when they looked for it again over the next several months. During Cassini's flyby on August 21, 2014, the object had "magically" reappeared and its appearance changed over the following 11 months.
The researchers believe the object could be "surface waves, rising bubbles, floating solids, solids suspended just below the surface, or perhaps something more exotic." The disappearance and reappearance of the feature could be linked to Titan's changing seasons.
"Science loves a mystery, and with this enigmatic feature, we have a thrilling example of ongoing change on Titan," said Stephen Wall, the deputy team lead of Cassini's radar team, based at NASA's Jet Propulsion Laboratory in Pasadena, California. "We're hopeful that we'll be able to continue watching the changes unfold and gain insights about what's going on in that alien sea."
The researchers hope to solve the mystery in future flybys in Cassini's extended mission.
"The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and ASI, the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries," NASA reported.
