island surrounded by methane and ethane

Titan’s Magic Island

Saturn’s largest moon, Titan, might be the most intriguing member of the solar system. It’s a primeval Earth, complete with an atmosphere, liquid bodies, and even suggestions of geological activity.

In 2013, the orbiting Cassini spacecraft spotted a brand new chunk of land that mysteriously appeared out of Titan’s second-largest sea, Ligeria Mare. Shortly thereafter, the “Magic Island” disappeared just as mysteriously into the translucent, –200 degree Celsius (–290 °F) methane-ethane sea. And then itreappeared again as a much larger landmass during one of Cassini’s recent radar sweeps of Titan.

The transient land confirms the supposition that Titan’s alien oceans and seas are dynamic components of an active environment, rather than static features. However, astronomers are at a loss to explain the physical processes responsible for the ephemeral landmass. Especially since it appears to have doubled in size—from 50 to 100 kilometers (30 to 60 mi) across—since it reappeared.