Instrument Information
IDENTIFIER urn:nasa:pds:context:instrument:visa.vo1::1.1
NAME VISUAL IMAGING SUBSYSTEM - CAMERA A
TYPE IMAGER
DESCRIPTION The Viking visual imaging subsystem (VIS) consisted of twin high-resolution, slow-scan television framing cameras mounted on the scan platform of each orbiter with the optical axes offset by 1.38 deg. The two cameras, including their housing, were 21.8 x 21.8 x 94.0 cm in size and had a mass of 40 kg. The VIS had four primary functions: to aid in the selection of landing sites that were both safe and scientifically interesting, to observe large scale features of the landing sites for correlation with lander data from the surface, to observe and map the planet for subsequent study of the geologic features of the planet, and to investigate the atmosphere of Mars. Individual images are identified by picture number (PICNO), which is a unique identifier of the scene. Elements of the PICNO are as follows: the first three digits denote the revolution (REV) during which the image was shuttered; the letter A is Viking Orbiter 1, B is Viking Orbiter 2; and the last two digits are the frame number.
MODEL IDENTIFIER
NAIF INSTRUMENT IDENTIFIER
SERIAL NUMBER not applicable
REFERENCES Benesh, M., and T. Thorpe, Viking Orbiter 1975 Visual Imaging Subsystem Calibration Report, JPL document 611-125, 1976.

Klaasen, K.P., T.E. Thorpe, and L.A. Morabito, Inflight performance of the Viking visual imaging subsystem, Applied Optics, 16, 3158-3170, 1977.

Wellman, J.B., F.P. Landauer, D.D. Norris, and T.E. Thorpe, The Viking Orbiter visual imaging subsystem, J. Spacecr. Rockets, 13, 660-666, 1976.