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Availability: Archived at NSSDC, accessible from elsewhere

Time span: 1972-12-12 to 1972-12-14


This description was generated automatically using input from the Planetary Data System.

Data Set Overview

This data set contains a table of readings from the Traverse Gravimeter Experiment performed during the Apollo 17 mission. The gravimeter, which recorded relative measurements of the local gravitational field at the lunar surface, was manually run by the astronauts near the Lunar Module landing site. The data table includes 23 valid gravity values, with calibrations and corrections, that were obtained from 12 to 14 December 1972; the results are discussed below. Supporting documentation includes the Apollo 17 Traverse Gravimeter Experiment Final Report by Buck, et al., (1973) [BUCKETAL1973].


The 26 readings of the Apollo 17 Traverse Gravimeter are provided as a fixed-width ASCII text table, A17_TRAVERSE_GRAVIMETER.TAB with a detached PDS label. The table contains 16 columns for each reading including the location, the elapsed time at which the measurement was initiated (hour, minute, and second), the displayed value, the difference between the displayed value and the value of the LM site, the raw delta G (gravity) value, the delta G value after application of an empirical correction, the elevation in meters, and comments. The table is a reproduction of the data found in Table 11-1 of the principal investigator's Traverse Gravimeter Experiment Final Report by Buck, et al., (1973) [BUCKETAL1973]. Additional information in the table such as the elapsed time of the reading was taken from the Apollo 17 Preliminary Science Report [APOLLOA1973] and the Apollo Science Experiments Data Handbook [APOLLOSEDH1974]. The column definitions in the PDS label provide descriptions of the contents.


The absolute value for the Lunar Module site was estimated to be 162,694.6 milligal with an uncertainty of 5 milligal. (One gal or galileo is defined as 0.01 meters per second-squared.) For a summary of errors assumed, see table 9-1, page 57 in Buck, et al. (1973) [BUCKETAL1973]. Based on knowledge of the instrument and the measurements it was assumed the instrument drift was negligible. The root-mean-square instrument noise value was given as 1.8 milligal based on values taken with the instrument off the Lunar Roving Vehicle at the Lunar Module site (readings 3, 9, 11, 17, 19, and 25). To convert the difference in the display readings to milligal, the higher order terms in the equation were neglected and the reading difference was simply multiplied by -0.03245. For more details see Chapter 13, Traverse Gravimeter Experiment, of the Apollo 17 Preliminary Science Report [APOLLOB1973].

Supporting Documentation

Traverse Gravimeter Experiment Final Report by Buck, et al., (1973) [BUCKETAL1973] is included in the DOCUMENT directory. It contains sections about the basic theory of interpretation of the results, a description of the equipment used, and analysis and discussion of the results. Twenty-three valid gravity values were obtained and published along with calibrations and corrections. The document was digitized from microfiche archived at the National Space Science Data Center with data set ID PSPG-00330 (72-096C-03A). Several figures and tables in final report are useful for understanding the Traverse Gravimeter data: - Gravity data table, Table 11-1, page 67 (PDF page 79) - Traverse map, Figure 11-2, page 69 (PDF page 81) - Summary of errors, Table 9-1, page 57 (PDF page 69) - Temperature alarms and codes, Table 7-2, page 45 (PDF page 57) - Thermal design cutaway, Table 7-2, page 32 (PDF page 44)

These data are available on-line from the Planetary Data System (PDS) at:

Alternate Names



  • Planetary Science: Geology and Geophysics

Additional Information



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



NameRoleOriginal AffiliationE-mail
Dr. Manik TalwaniData ProviderRice
Dr. David R. WilliamsGeneral
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