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Lander Radio Science

NSSDCA ID: 1975-075C-11

Mission Name: Viking 1 Lander
Principal Investigator:Dr. William H. Michael, Jr.


This experiment used the lander S-band radio transmitter to acquire Doppler and range data for the lander, utilizing the same Deep Space Network facilities that were used by the orbiters. The resulting data were used to determine the location of the lander on the planet's surface. They also provided more precise information about the orbital, rotational, and precessional motion of Mars than had previously been available. The two principal differences between orbiter and lander tracking data are (1) lander tracking periods were never longer than 2 h and were sometimes much shorter because of thermal constraints on the duration of lander transmitter operation, and (2) landers had no X-band signals to provide the corrections to range data for the interplanetary plasma effects. Consequently, lander ranging sessions were scheduled to be nearly simultaneous with orbiter ranging whenever possible, so that the orbiter S- and X-band data could supply these corrections.

Alternate Names

  • Viking1Lander/LanderRadioScience

Funding Agency

  • NASA-Office of Space Science (United States)


  • Planetary Science: Atmospheres

Additional Information

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



NameRoleOriginal AffiliationE-mail
Dr. William H. Michael, Jr.Team LeaderNASA Langley Research Center
Dr. Irwin I. ShapiroTeam MemberMassachusetts Institute of
Prof. G. Leonard TylerTeam MemberStanford
Mr. Dan L. CainTeam MemberNASA Jet Propulsion Laboratory
Dr. Mario D. GrossiTeam MemberRaytheon
Dr. Joseph P. BrenkleTeam MemberNASA Jet Propulsion Laboratory
Dr. Robert H. TolsonTeam MemberNASA Langley Research
Dr. J. G. DaviesTeam MemberUniversity of Manchester
Dr. Charles T. StelzriedTeam MemberNASA Jet Propulsion
Dr. George H. BornTeam MemberNASA Jet Propulsion
Dr. Robert D. ReasenbergTeam MemberMassachusetts Institute of
Dr. Gunnar F. LindalTeam MemberNASA Jet Propulsion Laboratory

Selected References

  • Michael, W. H., Jr., et al., The Viking radio science investigations, J. Geophys. Res., 82, No. 28, 4293-4295, doi:10.1029/JS082i028p04293, Sept. 1977.
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