Strange ‘magic islands’ on Saturn’s moon Titan may be porous iceberg

The seas of Saturn’s moon Titan have bizarre “magic islands” that appear to look and disappear over the course of hours to weeks. These so-called islands may really be porous, sponge-like clumps of snow that slowly refill with fluid after which sink.

Titan’s thick ambiance is filled with complicated natural molecules that may clump collectively and fall right down to the moon’s floor like snow. Xinting Yu on the University of Texas at San Antonio and her colleagues thought the “snow” may be accountable for the magic islands. To check their thought, they used what we learn about these atmospheric compounds and the way they’re anticipated to work together with Titan’s seas.

Typically, we anticipate any solids on the surfaces of those seas to sink instantly as a result of the liquid on Titan is methane fairly than water. While water molecules are inclined to cling to 1 one other and push away different supplies, methane simply grabs on to different molecules, so a pool of liquid methane has little or no floor stress.

“Water molecules just love themselves to the exclusion of some types of molecules,” says Michael Malaska at NASA’s Jet Propulsion Laboratory in California, who was not concerned on this work. “But put methane on the same surface and it will crawl all over.” That signifies that the methane oceans and lakes on Titan ought to instantly swallow up any solids, even people who may in any other case be anticipated to drift.

But that clearly doesn’t occur with the magic islands, which appeared as ephemeral vivid spots in observations from the Cassini spacecraft. “For us to see the magic islands, they can’t just float for a second and then sink,” Yu mentioned in a press release. “They have to float for some time, but not for forever, either.”

The researchers discovered an answer to this downside: if massive chunks of snow amassed on the shore, they might kind ices which are filled with holes, like sponges. When these porous “icebergs” broke off from the land, they might float on Titan’s seas for lengthy sufficient to match the Cassini observations. This would work if, the researchers calculated, the sponge-like constructions contained sufficient empty house – a minimal of about 25 to 50 per cent relying on the precise composition of the ice.

This doesn’t imply that the mysterious islands are undoubtedly porous icebergs, although. “We are narrowing the different scenarios for the magic islands, but we still don’t yet know the answer,” says Malaska. Other doable explanations embody bubbles of nitrogen fuel, waves brought on by wind or strong sediments within the oceans. But this does present proof that Titan’s transitory islands may really be floating matter from this unusual world’s ambiance.