CLEM RSS Gravity Reduced Data Record (GRAV)

GRAV – Gravity Reduced Data Record

Instrument:Radio Science Subsystem

PDS3 Data Set ID: CLEM1-L-RSS-5-GRAVITY-V1.0DOI: 10.17189/1520094

PDS4 Bundle:urn:nasa:pds:clementine1_gravity_and_topographyDOI: 10.17189/nc87-0q13

LRO PDS3 to PDS4 Migration Status: Complete

For additional information regarding the RSS GRAV products, please refer to the PDS4 Bundle Information File or the PDS3 Data Set Catalog File.

The Radio Science Subsystem (RSS) Gravity Reduced Data Record (GRAV) data products contain information about the gravitational signature of the Moon as determined by velocity perturbations of the Clementine spacecraft measured from the Doppler shift of the S-band radio tracking signal.

The Clementine data were combined with S-band tracking observations from Lunar Orbiters 1, 2, 3, 4, and 5 and from the Apollo 15 and 16 subsatellites. With the exception of the Lunar Orbiter 4 and 5 spacecraft, these spacecraft lacked the global coverage of Clementine, but most had lower periapsis altitudes and thus provided distributed regions of short-wavelength resolution in the vicinity of spacecraft periapses (generally ± 40 degrees latitude).

The bundle includes a gravity data collection and a gravity image collection. Each product in this bundle is described by a PDS4 label in a separate file with the same name as the file described by the label but with the extension .xml. PDS4 labels are XML (eXtended Markup Language) files that conform to the PDS4 Information Model XML schema and schematron at https://pds.nasa.gov/pds4/schema/released/. The PDS4 labels are best viewed in an XML-aware text editor, and may be used by software that can manipulate XML documents.

RSS GRAV products have the following file names:

product.xxx (with detached PDS labels for each file)

where:

product = product name

FAIRGRD1 = free-air gravity anomalies at 1 degree resolution

FAIRGRD2 = free-air gravity anomalies at 0.25 degree resolution

FAIRERR1 = free-air gravity errors at 1 degree resolution

FAIRERR2 = free-air gravity errors at 0.25 degree resolution

BOUGGRD = Bouguer gravity anomalies

GEOIDGRD = geoid anomalies

GEOIDERR = geoid anomaly errors

THICKGRD = effective crustal thicknesses

xxx = file extension

DAT = ASCII data table

TAB = ASCII data table

IMG = image file

There is an additional product named GLGM2SH.TAB, with its corresponding label file, which is a 70th degree and order spherical harmonic gravitational field model.

In ODE, GRAV products have the following product IDs:

PRODUCT

PRODUCT_IMG

GLGM2-SH