In this 4 minutes and 40 seconds movie released in January 2005 by ESA/NASA/JPL/University of Arizona, you can see the Huygens probe plunging through Titan's thick orange-brown atmosphere to a soft sandy, dry riverbed.
If you haven't seen it, it's worth a look-see.
At first, the Huygens camera just saw fog over the distant surface. The fog started to clear only at about 60 kilometers (37 miles) altitude, making it possible to resolve surface features as large as 100 meters (328 feet). Only after landing could the probe's camera resolve the little grains of sand. The movie provides a glimpse of such a huge change of scale.
The Huygens probe was delivered to Saturn's moon Titan by the Cassini spacecraft, which is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif. NASA supplied two instruments on the probe, the descent imager/spectral radiometer and the gas chromatograph mass spectrometer.
