There’s no Stonehenge on Titan, Saturn’s largest moon, but NASA scientists are celebrating its summer solstice anyway with the discovery of what some are calling a “magic island” – a large now-you-see-it-now-you-don’t spot among smaller ones in a lake that could be a floating methane iceberg. With the warmer temperatures of a Titan summer approaching, NASA scientists are hoping for some big summer storms that will stir up the lakes and rivers and splash up even more new stuff to study.
According to a report this week in Nature Geoscience, the large spot was discovered in 2013 by the Cassini spacecraft and is located in the hydrocarbon lake Ligeia Mare. Titan and Earth are the only bodies in the solar system with seas, lakes and rivers. Titan’s of course are filled with ethane, methane and propane and, until this discovery, were mysteriously smooth. Mysterious because the rest of Titan has features created by wind but the lakes have no visible waves.
The scorching summer heat on Titan is a little different than on Earth. Its surface temperature is -297 degrees Fahrenheit (-183 degrees Celsius) which is slightly below the freezing point of methane (-295.6 F (-182°C)). The difference in temperatures between Titan’s winter and summer is slight – summer is just a few degrees warmer – but it’s enough to possible affect the weather, melt methane ice and create bubbles and waves that might surface some other solids.
The spot has been dubbed a “magic island” because it has disappeared and reappeared on images sent back by Cassini since the initial discovery in 2013. Whatever it is, it will tell us more about Titan and possibly about Earth, according to study lead author Jason Hofgartner, a graduate student at Cornell University in New York.
Likely, several different processes – such as wind, rain and tides – might affect the methane and ethane lakes on Titan. We want to see the similarities and differences from geological processes that occur here on Earth.
If there’s life on Titan, I wonder if they’re arguing about the cause of this global warming.