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Mars Atmospheric Water Detector (MAWD)

NSSDCA ID: 1975-083A-03

Mission Name: Viking 2 Orbiter
Principal Investigator:Dr. Crofton B. Farmer

Description

The MAWD used an infrared grating spectrometer mounted on the orbiter scan platform that was boresighted with the television cameras and the IRTM. The instrument measured solar infrared radiation reflected from the surface through the atmosphere to the spacecraft. Spectral intervals were selected coincident with the wavelength of water vapor absorption lines in the 1.4-micrometer band. The quantity of water vapor along the line of sight was measured from 1 to 1000 micrometers of precipitable water with an accuracy of 5 % or better. The instantaneous field of view of the instrument was 2 x 17 milliradians, and a stepping mirror rotated the line of sight through 15 positions to provide a roughly rectangular field of view of 17 x 31 milliradians.

Alternate Names

  • MAWD
  • Viking2Orbiter/MAWD
  • urn:nasa:pds:context:instrument:mawd.vo2

Funding Agency

  • NASA-Office of Space Science (United States)

Disciplines

  • Planetary Science: Atmospheres
  • Planetary Science: Geology and Geophysics

Additional Information

Questions and comments about this experiment can be directed to: Dr. David R. Williams

 

Personnel

NameRoleOriginal AffiliationE-mail
Dr. Crofton B. FarmerTeam LeaderNASA Jet Propulsion Laboratorybfarmer@mail2.jpl.nasa.gov
Mr. Dan LaporteTeam MemberSanta Barbara Research Center
Dr. Donald W. DaviesTeam MemberNASA Jet Propulsion Laboratoryddavies@rainbow.sp.trw.com

Selected References

  • Farmer, C. B., and D. D. Laporte, The detection and mapping of water vapor in the Martian atmosphere, Icarus, 16, No. 1 34-46, doi:10.1016/0019-1035(72)90135-2, Feb. 1972.
  • Farmer, C. B., et al., Mars: Northern summer ice cap -- Water vapor observations from Viking 2, Science, 194, No. 4271, 1339-1341, doi:10.1126/science.194.4271.1339, Dec. 1976.
  • Davies, D. W., et al., Behavior of volatiles in Mars' polar areas - a model incorporating new experimental data, J. Geophys. Res., 82, No. 26, 3815-3822, doi:10.1029/JB082i026p03815, Sept. 1977.
  • Jakosky, B. M., et al., The observed day-to-day variability of Mars atmospheric water vapor, Icarus, 73, No. 1, 80-90, doi:10.1016/0019-1035(88)90086-3, Jan. 1988.
  • Farmer, C. B., et al., Mars: Water vapor observations from the Viking Orbiters, J. Geophys. Res., 82, No. 28, 4225-4248, doi:10.1029/JS082i028p04225, Sept. 1977.
  • Jakosky, B. M., and C. B. Farmer, The seasonal and global behavior of water vapor in the Mars atmosphere: Complete global results of the Viking Atmospheric Water Detection Experiment, J. Geophys. Res., 87, No. B4, 2999-3019, doi:10.1029/JB087iB04p02999, Apr. 1982.
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