Titan, Saturn’s largest moon, confounded scientists with the mystery of its “magic islands” until a new study offered an explanation.
CNN reports that the mystery of the disappearing islands first came to light when NASA’s Cassini space probe surveyed the large moon in 2013. The craft recorded radar images of bright areas in Titan’s second largest sea, named Ligeia Mare.
The sea itself is about 50% larger than Earth’s Lake Superior and is made of a liquid mix of methane, nitrogen, and ethane. Cassini recorded what appeared to be images of islands appearing and then disappearing in Ligeia Mare.
Researchers now believe that the apparent islands are actually collections of thousands of bubbles. When streams of large bubbles reach the surface, the resulting look is that of an island forming on the sea.
The study suggests that the bubbles are formed when the elements present in the sea destabilize in the cold, high-pressure depths. Earth has no equivalent effervescent effect in any of its oceans.
Titan is the only moon in the solar system to sport clouds and a dense atmosphere. Titan has lakes and rivers and rain of liquid ethane and methane. Scientists suspect that Titan also harbors a subsurface liquid water ocean.
Scientists are still unsure as to how Titan came to possess its thick, complex atmosphere and from where the moon’s methane originates.
“In the future, perhaps we will discover some ‘exo-Titan’ among exoplanets, making our Titan the prototype of a new class of celestial objects,” Daniel Cordier of the Centre National de la Recherche Scientifique in Paris said.
The study was published in Nature Astronomy.