January 15, 2005


Lakefront Landing in Crème Brulé (Henry Bortman, January 14, 2005, Astrobiology)

Huygens, scientists say, has landed in soil with the consistency of wet sand or clay - or, as John Zarnecki, the principal investigator for Huygens' Surface Science Package, said one team member had suggested, "crème brulé." The scenery surrounding the landing site resembles a postcard panorama of undeveloped lakefront property, hand-tinted in pastel shades of orange.

It's hardly a typical lakefront, though - and not just because everything, including the sky, is orange. For starters, the temperature on Titan averages about minus 180 Celsius (minus 292 Fahrenheit). It makes the shore of Lake Michigan on a windy night in January seem balmy by comparison.

Then there's the composition of the liquid in the "lake." It's not water. On the surface of Titan, water is frozen as solid as granite. It's more likely liquid methane or ethane, perhaps a mixture of the two. In other words, it's a lake of liquid natural gas.

Researchers expected that, because of the high concentration of methane in Titan's atmosphere, they would find bodies of liquid methane on the surface. Some even proposed the possibility that Titan could be covered by a global methane ocean. The latter possibility can now be crossed off the list, although it's important to note that Huygens examined only one tiny spot on Titan. And Cassini, the orbiting spacecraft that delivered Huygens to Titan, has only made three passes by the giant moon and has looked in detail at only a few small strips of the surface. More than 40 additional flybys are planned during the 4 years of Cassini's primary mission. It's still possible that some other location on Titan will reveal the presence of an ocean-sized body of liquid.

Posted by Orrin Judd at January 15, 2005 9:24 PM
Comments for this post are closed.