The View from Huygens

by | Jan 6, 2005 | Outer Solar System

When the Huygens probe descends through Titan’s atmosphere on January 14, only one optical instrument will be available for imaging. The Descent Imager/Spectral Radiometer (DISR) will take photographs of the surface during the two-hour descent, relaying the data to the Cassini orbiter for re-transmission to the Deep Space Network. Martin Tomasko of the University of Arizona’s Lunar and Planetary Laboratory leads the international team in charge of DISR; he and other UA colleagues will head for the European Space Operations Center in Darmstadt, Germany next week.

Key points:

  • The Huygens probe should emerge from Titan’s haze layer at an altitude of about 43 miles (70 kilometers), allowing the DISR instrument to get clear views of the descent and the surface below.
  • The instrument’s three cameras will take 750 images, which will be merged into a series of panoramic views of the ground and horizon.
  • All DISR data will be relayed to Cassini at a height of 12 miles, to guard against the loss of the lander on impact.
  • As the descent continues, the instrument will examine light spectra from Titan’s surface to study the makeup of its surface features.
  • At approximately 700 meters altitude, a 20-watt lamp attached to the DISR will switch on to, as the University of Arizona Lunar and Planetary Laboratory puts it, “… replace the colors of sunlight filtered out by Titan’s atmospheric methane.”
  • Thirty minutes of battery power should remain for continuing data transmission if Huygens does survive the landing.

    • The first data should arrive shortly after 2 PM EST on Friday January 14. Images should be available by the early morning of the 15th. A news conference will be held the same morning at ESOC to present initial results.

    We are now seven days away from the most distant landfall ever attempted.

    Sources: University of Arizona Lunar and Planetary Laboratory press release; Jet Propulsion Laboratory. Also, check the Cassini VIMS Science Investigations site for information about the Visual and Infrared Mapping Spectrometer aboard the orbiter.