Day 66: Oh, to hike on Mars or Titan

Artist's depiction of a scene on Saturn's moon Titan, using Cassini data. Credit: Michael Carroll

Ever see pictures of the other planets and fight the ridiculous urge to pack a picnic, or don the hiking boots for a little interplanetary adventure? I do. With all the images now coming back from Mars, for example — and the fact that the surface boasts as many named features as some of our more popular national parks — the place is beginning to occupy my consciousness as another wilderness, a new personal frontier. 

And if that’s not bad enough, there’s Titan, Saturn’s biggest moon. Neither I nor my descendants will be likely to visit, and that’s a good thing — the cold and the chemistry would be deadly. And yet … Titan seems to beckon me. And I know that if I were a rich space traveler like Charles Simonyi in a future age, I’d probably take the chance to go.

I first learned about Saturn’s great moon Titan when I was a science reporter at the Arizona Daily Star, covering the Huygens probe that separated from Cassini in late 2004 to land on the bizarre moon’s surface. I remain enthralled by the place, where climate cycles are dominated not by water (that would be unlikely at -300 degrees F) but instead by thick, dark hydrocarbons. Methane and ethane fill the air with a smoggy haze that rains down as ash. Sometimes it’s washed away by hydrocarbons that flow like gasoline; other times the hydrocarbons form thick goo on the surface. Some of the compounds collect in black lakes with surfaces as smooth as glass; astronomers have puzzled over the shores of these bodies.

In the artist’s rendering above, a short but fierce “gullywasher” rainstorm of methane is falling on the mountains surrounding the intriguing flows of Titan’s Hotei Arcus, which forms the boundary between rugged mountains to the south and east and a broad valley. Emerging from the mountains are several probably dry river beds that were carved by flowing methane. Within the valley, the channels end near lobate (blobby) flows some 300 to 600 feet thick, which some scientists think could be slushy ice lava. The depiction uses data from the  Cassini spacecraft, which remains in orbit around Saturn to chronicle the giant planet and its moons. Randoph Kirk, a geologist with the U.S. Geological Survey in Flagstaff, presented it as part of a series of new Titan surface maps, at the Lunar and Planetary Science Conference last week in Texas.

A true alien world, Titan must be — but with enough elements like our own to be haunting in its parallels. We could not live there, but possibly other forms of life have evolved. It would be killing cold, smelly, toxic. And beautiful. 

As Huygens landed in early 2005, it sent back tantalizing images of its dry riverbed landing site (left), filled with hydrocarbon ash and these pebbles. Due to the smoggy haze that fills the moon’s atmosphere, this is probably pretty close to the way the place would look on the surface.  (You could hike forever on a surface like that!)

The Sun, already more distant from Titan than it is from Earth, would be shrouded a bit, as if shining through smoke from a wildfire. 

And let’s cast all reason aside with regard to the temperature, and pretend for a moment that you’d be sweaty from a day of hiking in that place. Well, by all means, then, have a swim! Not a soul to see you up there …

 

An artist's imagination of hydrocarbon pools, icy and rocky terrain on the surface of Saturn's largest moon Titan. Image credit: Steven Hobbs (Brisbane, Queensland, Australia).

More information about the Cassini-Huygens mission is here.