Huygens Probe Descends on Titan
Cassini, the NASA/JPL spacecraft currently in orbit around magnificent Saturn, is about to release a probe. On December the 24th, the European Space Agency (ESA) designed and built Huygens Probe will be released on a glide path calculated to insert it on a landing trajectory on Saturn’s largest moon, Titan. The landing is scheduled for January 14th, 2005.
The Huygens Probe is named after the multi-talented Dutch scientist Christiaan Huygens, who discovered Titan and Saturn’s rings in the 17th century.
According to Solarviews:
Although Titan is classified as a moon, it is larger than the planets Mercury and Pluto. It has a planet-like atmosphere more dense than Earth’s. Titan’s air is predominantly made up of nitrogen with other hydrocarbon elements which give Titan its orange hue. These hydrocarbon rich elements are the building blocks for amino acids necessary for the formation of life. Scientists believe that Titan’s environment may be similar to that of the Earth’s before life began putting oxygen into the atmosphere.
Titan’s surface temperature appears to be about -178°C (-289°F). Methane appears to be below its saturation pressure near Titan’s surface; rivers and lakes of methane probably don’t exist, in spite of the tantalizing analogy to water on Earth. On the other hand, scientists believe lakes of ethane exist that contain dissolved methane. Titan’s methane, through continuing photochemistry, is converted to ethane, acetylene, ethylene, and (when combined with nitrogen) hydrogen cyanide. The last is an especially important molecule; it is a building block of amino acids.
According to Space.com:
The descent through Titan’s atmosphere is carefully choreographed, with a series of parachutes deploying at certain intervals to slow the probe’s downward trajectory. Once the velocity is slow enough and temperatures are safe, the heat shield at the bottom of the spacecraft will be jettisoned and the scientific instruments it was protecting can begin to take data. These instruments include the Gas Chromatograph Mass Spectrometer (GCMS) and the Aerosol Collector and Pyrolyser (ACP), both of which will measure the composition of Titan’s atmosphere.
The Huygens Atmospheric Structure Instrument (HASI) will deploy on a boom to measure the structure of Titan’s atmosphere, including its density, pressure, and temperature at various altitudes, and the Descent Imager / Spectral Radiometer (DISR) camera will begin taking panoramic images as the spacecraft spins on its parachute. DISR is planned to take more than 1100 images during the descent.
I hope everything works. This should be fascinating. Lakes of ethane. Now that’s cold!
More: Cassini-Huygens Website