Among the many scientific achievements of Huygens was the first ever recording of sounds sent back from another world.
During the long parachute descent through the satellite’s dense atmosphere, the sounds of Titan were collected by a “microphone” outside the probe.
At the same time, the radar altimeter on Huygens was bouncing radio signals off Titan’s surface.
1. Speeding through Titan’s haze
.myLink {color:blue}.myLink:hover {color:aa3333;text-decoration:underline}This recording is a reconstruction of the sounds heard by Huygens’ microphone. Several sound samples, taken at different times, have been combined into a one minute sound track.
The result is a realistic reproduction of what a traveller on board Huygens would have heard during the descent. Changes in loudness may be caused by gale force winds, rain or thunder.
File 1 : acoustic during descent
2. Radar echoes from Titan’s surface
.myLink {color:blue}.myLink:hover {color:aa3333;text-decoration:underline}This recording was produced by changing into sounds some of the radar echoes received by Huygens during the last few kilometres of its descent. As the probe approaches the ground, the pitch and intensity increase – rather like the sound of a motorcycle revving up.
By analysing the echoes, scientists will be able to calculate changes in the probe’s altitude. They may even be able to tell whether the surface was solid or liquid, rough or smooth.
File 2 : radar conversion
Credit: ESA/NASA/ASI/HASI team (M. Fulchignoni)
