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Metadata Updated: December 6, 2023

This data set consists of the raster-averaged radiant intensities and associated data parameters produced from data acquired by the Mars Atmospheric Water Detectors (MAWD) onboard the Viking Orbiters. The basic observations give temporal coverage spanning just over two martian years and variable, but extensive, spatial coverage of the planet. MAWD was a five-channel grating spectrometer measuring solar radiation reflected from the surface and atmosphere of Mars in and out of water vapor bands in the 1.4 micrometer spectral interval. The data set described here contains the solar reflected radiant intensities (i.e., radiances) measured by MAWD, derived water vapor column abundances, a derived '1.4-micrometer brightness', and ancillary data (e.g., viewing geometry, surface elevation and air mass). Column water vapor abundances were derived by comparing the reflected radiant intensities in three water vapor absorption bands to radiant intensities in the two interspersed continua observed air mass and then normalized by the air mass to obtain a vertical column abundance. A basic description of the instrument, its observational modes and its derived data products is given in [FARMER_ETAL_1977]. A description of the global and seasonal variation of water vapor on Mars, based on the complete MAWD observational record, is given in [JAKOSKY_FARMER_1982]. This data set was generated from the raster-level data base constructed during the Viking Mission on the original data processing system (IRPS: Infrared Processing System) by the MAWD Science Team, led by C. B. Farmer, JPL. Together with the instantaneous field of view (IFOV) radiances and geometry, the raster-level radiances, associated water column abundances and ancillary data have been archived at the NSSDC (NSSDC id 75-075A-03A, 75-083A-03A). Data from the final phase of the VO-1 mission were added, supervised by R. Zurek, JPL. Eventually, the data set was restructured, additional quality flags were introduced, and a second estimate of the water vapor column abundance (WFAPT, termed COLUMN_H2O_A in the data set) was added [by R. Zurek, JPL [JAKOSKY_ETAL_1988].]. The data base was restructured, while preserving key unique parameters, into a consistent format with the Viking Orbiter Infrared Thermal Mapper (IRTM) data [R. Mehlman, R. Zurek]. Both the MAWD and IRTM data sets were then accessible with the XXFUNC package. Further quality checking of the MAWD data was carried out by B. Jakosky, U. Colorado.

Access & Use Information

Public: This dataset is intended for public access and use. License: us-pd

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Metadata Created Date January 31, 2023
Metadata Updated Date December 6, 2023
Data Update Frequency irregular

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date January 31, 2023
Metadata Updated Date December 6, 2023
Publisher National Aeronautics and Space Administration
Identifier urn:nasa:pds:context_pds3:data_set:data_set.vo1-vo2-m-mawd-4-v1.0_4qcq-qd8s
Data First Published 2021-05-21
Data Last Modified 2023-01-26
Category Earth Science
Public Access Level public
Data Update Frequency irregular
Bureau Code 026:00
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id db51f1eb-6e5e-4078-bf4a-5665536ee45a
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL
Program Code 026:005
Related Documents
Source Datajson Identifier True
Source Hash a3f0fee29635b8b1a9a624e89f37079eb75f6456a47a095d712ebec4ade9d51a
Source Schema Version 1.1

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