It’s been thought for some time that liquid might exist on Titan, and given its dense atmosphere that’s loaded with hydrocarbons, methane or ethane is a good guess. But evidence has been scant. The best so far was when the Huygens probe, launched by Cassini to land on Titan, appeared to have squished down in mud!
The image above, taken using the Cassini probe’s radar. It’s the shape of the features that’s interesting: sharp-edged, yet with rounded contours. That, plus the fact that liquid methane and ethane absorb radar, making them look dark just like those features, is very provocative. Cassini scientists are excited about the images, so I’m sure we’ll be hearing lots more about this very soon.
People will inevitably wonder if this has any impact on life evolving on Titan. Beats me. We really have no clue how life first sparked on Earth. We need liquid water now, but as far as I know it’s not clear exactly what Earth was like when life first arose (any biologists or archaeologists wanna enlighten us physical scientist-types about this?). And does that situation apply to Titan, with twice the Earth’s atmospheric pressure and temperatures of -180 Celsius?
Still and all, liquid existing on the surface of another world is really exciting. The more we look at other worlds, the more alien we realize they are… but the more like home as well.