Temperature Profile from Pathfinder Atmospheric Structure Instrument

This figure compares the most recent temperature profile derived from the Pathfinder ASI accelerometer data during entry, with the Viking 1 entry profile. The nominal profile is given by the solid red line and the thin red lines represent error estimates. Also shown is the temperature profile (Green) for which the saturated vapor pressure of CO₂ is equal to the atmospheric pressure. At 80 km, the Pathfinder entry profile falls below the CO₂ profile, and it is possible that CO₂ ice clouds could form at this level. This profile also shows a temperature inversion at 10-12 km, which may mark the location of the water vapor ice clouds seen in the IMP camera sunrise images.

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

Photojournal note: Sojourner spent 83 days of a planned seven-day mission exploring the Martian terrain, acquiring images, and taking chemical, atmospheric and other measurements. The final data transmission received from Pathfinder was at 10:23 UTC on September 27, 1997. Although mission managers tried to restore full communications during the following five months, the successful mission was terminated on March 10, 1998.