Space travelers seeking to take a swim now have a whole new world of possibilities. A spacecraft orbiting Saturn has spotted evidence of a lake on its largest moon, Titan, making this the first time scientists have found a body of liquid on an object other than our home planet. The researchers announced their findings today in the journal Nature, and the University of Arizona issued a news release about the discovery, which was made by one of its scientists.

Anyone contemplating a dip in this lake, called Ontario Lacus (at right), will want to wear a thick wet suit. The temperature on the surface of Titan is minus-290 degrees Fahrenheit, and the lake is likely to consist of liquid hydrocarbons such as ethane and methane.

The evidence in the new study was collected by the Cassini spacecraft in orbit around Saturn. Planetary researchers have long suspected that Titan harbored hydrocarbon oceans or lakes, but clear evidence of any liquid body has been difficult to find.

An instrument aboard Cassini has now captured telltale signs of liquid ethane in Ontario Lacus, which is 150 miles long. In 2004, Cassini dropped a probe to the surface of Titan that found evidence that liquid hydrocarbons rain onto the surface of the moon. —Richard Monastersky