Titan Close Up
January 14, 2005
|Channel-like landscape from 16 kilometers, at 40 meters per pixel resolution during descent. Click image for larger view. |
Image Credit: ESA
The European Space Agency has released the first 3 of several hundred images captured by the Huygens probe during its descent through the atmosphere of Saturn’s giant moon Titan. Although the images have not yet been cleaned up – they were released in their raw form – they reveal a world of diverse landforms, shaped at least in part by fluid erosion. Two of the images are reminiscent of early photographs of Mars.
The left half of the first image, taken from a height of 16 kilometers (10 miles) above Titan’s surface, shows a pattern of branching channels that look like canyons on Earth cut by water. It’s unlikely that water was responsible in Titan’s case, though; Titan is far too cold for liquid water to flow on its surface. Scientists say it’s too early to speculate about what the fluid might be.
On the right side of the image is a large flat dark area that is being interpreted initially as a large body of liquid with a visible shoreline. This is the first image of Titan that seems to confirm scientists’ speculation that Huygens would find large pools of liquid hydrocarbons, methane or ethane, on the moon’s surface.
The second image, taken from 8 kilometers (5 miles) above the surface, shows a hodge-podge of light and dark areas that are more difficult to interpret. The darker areas may be bodies of liquid as well. More work is needed to be certain. In the coming hours and days, image-processing teams will enhance the contrast of this and other images and clean up artifacts in attempt to extract more detail. This will then be combined with spectroscopic data that will tell scientists how reflective various areas of the image are. Combining imaging and reflectance data will help scientists figure out what they are looking at.
|Titan image from Huygens probe January 14, 2005–8 kilometer altitude, 20 m/pixel resolution. Click image for large view. [Banner image is false color view of the region near where Huygens came to rest.]|
Image Credit: ESA
The third image is perhaps the most stunning of all. It was taken from the surface of Titan, and shows a plain of what appear to be boulders stretching to the horizon. At first glance, it resembles a martian landscape.
"The amazing thing to me is how familiar this kind of scene seems. All of us on Earth see scenes not so different from this all the time. We see boulders strewn around. We’ve seen things that kind of look like this on Mars. We’ve seen things that look like this everywhere," said Marty Tomasko, the principal investigator for Huygens’ camera, the Descent Imager/Spectral Radiometer (DISR).
"These probably are not really rocks of silicate. These are probably blocks of ice, perhaps water ice frozen solid. The temperatures on Titan are so cold that water would be as stiff and as hard as a boulder would be on the Earth," he said.
"But there are questions that come to mind, too. How did this scene get produced? What physical processes happened on the surface to produce this? What kinds of motion, and the uplift, and the breaking of the rocks and the migration of the rocks – there are lots of questions that people will be debating."
|Surface image from Titan shows ice blocks strewn around. Click image for larger view. Image Credit: ESA|
That debate has already begun, as the Huygens image-processing team and data-processing teams from Huygen’s other instruments hunker down to work through the night in an effort to turn the billions of bits of raw data returned by Huygens into meaningful information.
There is one sour note to the day’s events. Only one of Huygens’ two communications channels functioned properly, resulting in a significant loss of data. One set of missing data was designed to help scientists learn about wind speeds in Titan’s atmosphere. Fortunately, scientists will be able partially to reconstruct the wind-speed information by studying variations in the frequency of the Huygens carrier signal detected on Earth by a global network of large radio telescopes.
Also lost, however, were half of the images captured by Huygens. This may make it difficult to construct the panoramic mosaic images that Tomasko’s team was hoping to produce.
Related Web Pages
Rendezvous with Titan
Huygens, Phone Home
Saturn– JPL Cassini Main Page
Lord of the Rings
Space Science Institute, Imaging Team Boulder, Colorado
Saturn: The Closest Pass
Where is Cassini Now?