17 December 2010
Saturn’s largest moon, Titan, is made up mainly of water, ice and mountains. Now scientists think they’ve found a mountain that spews lava made not of molten rock, but ice. The observation was announced at the American Geophysical Union meeting in San Francisco. Jonathan Amos reports.
Click to hear the report:
Titan is a mysterious world. Because it's shrouded in a thick, oily haze, it's extremely hard to identify anything at the moon with confidence. But with temperatures that plunge to minus 180 Celsius at the surface, researchers had suspected it might have ice volcanoes.
And now the Cassini probe has spotted a 1,500m-high mountain with a deep pit in it, and what looks like a flow of material nearby.
Scientists can only speculate what sort of material a cryo-volcano might erupt, but the complex chemistry at Titan suggests it could be a slushy water-ice containing ammonia.
If there are a lot of carbon molecules present, the lava could even look like softened asphalt, candle wax or even polyethylene.
The team which discovered the mountain have dubbed it "the Rose".
Jonathan Amos, BBC News
Click to hear the vocabulary:
partly hidden or covered
a mist or substance in the air which partly obscures what is behind it
to fall quickly
here, an unmanned spacecraft which has been launched from Earth to study Saturn and Titan
seen or identified
guess about the nature of something
here, when the volcano violently throws out material that is inside it
the smallest, most basic elements which make up a chemical substance
named in an unofficial or affectionate way