NSSDCA ID: PSPG-00299
Availability: At NSSDC, Ready for Offline Distribution (or Staging if Digital)
Time span: 1976-07-20 to 1982-11-13
This data set contains data on the rock population near the Viking 1 and 2 Landing sites. The data is in the form of tables giving rock locations, dimensions, orientation, number density, areal coverage as a function of rock diameter, axial ratios, and areas for rocks and of rock distributions according to surface type. The data were derived from Viking Lander images for 425 rocks (plus 2 possible outcrops) located near the Viking 1 Lander site and 499 rocks near the Viking 2 Lander site.
The basic tables include three types of information: (1) the xyz-coordinates; (2) the lengths, widths, and heights; and (3) a descriptor of the apparent burial state of each rock. Length is the longest visible (horizontal) dimension, width is the orthogonal horizontal dimension, and height H is the vertical exposure of the rock above the surrounding surface. The burial descriptors are subjective and include three categories: 'perched', 'partly buried', and 'deeply buried'. The rock size-frequency and size-area distributions were obtained from images and maps of surface materials by estimating the areas occupied by materials within the camera fields of view. A composite distribution function for about 80 square meters at each site. Derivative tables include parameters such as the average axial ratio for rocks computed from each pair of rock dimensions and the number density and areal converage of rocks as a function of diameter.
FORTAN 77 source code for statistical analysis of the files of basic rock data can be found in the SOFTWARE directory. The program will recreate rock number density and areal coverage statistics from the basic rock data. Intermediate results are also output. The VOLUME_ID for the data set is VL_9001, the PDS ID is VL1/VL2-M-LCS-5-ROCKS-V1.0.
Questions and comments about this data collection can be directed to: Dr. David R. Williams
Name | Role | Original Affiliation | |
---|---|---|---|
Dr. Richard A. Simpson | General Contact | Stanford University | rsimpson@magellan.stanford.edu |