Viking 1 and 2 Lander Footpad Temperature Sensor Data after Landing (PDS)

Description

This data set contains the Viking 1 and 2 Lander near-surface temperatures as measured by the thermocouple footpad temperature sensors. The data include point-by-point individual footpad temperature measurements and footpad temperatures averaged over one martian day (sol).

The point-by-point data (PDS ID VL1/VL2-M-FTS-3-FOOTPAD-TEMP-V1.0) include, for each measurement, the spacecraft (VL1 or VL2), local day and time, areocentric longitude of the Sun at the time of measurement, and the footpad temperature in degrees Kelvin. The data was taken at time intervals ranging from less than a second to 40 minutes. The data were edited to remove communications errors and other bad measurements.

The sol-averaged data (PDS ID VL1/VL2-M-FTS-4-SOL-AVG-FTPD-TEMP-V1.0) include the spacecraft ID, local date of measurement, areocentric longitude of the Sun at the beginning of the day, average footpad temperautre in degrees Kelvin, minimum daily temperature, daily measured temperature range, standard deviation of daily average, and length and time of the maximum daily measurement time gap.

The data are in PDS format with detached labels. Ancillary documentation is also included with this data set. The volume is in ISO-9660 format. This data is available online from the PDS Planetary Atmospheres Node. This is volume VL_1002.

Footpad temperature measurements were taken throughout the mission but were generated in edited and summarized format only after raw spacecraft mission data processing was implemented and formally begun. These measurements from Viking Lander 1 were archived beginning at sol 1008 (May 22, 1979) and ending at sol 2245 (Nov. 13, 1982), the Lander's last downlink. For Viking Lander 2, data were archived beginning at VL2 sol 1000 and ending on sol 1050, which was the last high quality downlink.

The footpad temperature sensors were part of the atmospheric structure experiment and were designed to measure atmospheric temperatures during the descent phase of the mission. They were not necessarily designed to provide precise temperature measurements after landing. The landed sensor was strongly affectedd by the ambient temperature of the lander, shading, and wind direction. Furthermore, the Viking 1 Lander sensor was buried under about .165 meters of soil after landing while the Viking 2 Lander sensor was not.