Planetary and lunar
Researchers of the Western Australian Geodesy Group have developed high-resolution gravity field models for Moon and Mars, which are freely available for science and education.
Lunar Gravity Model 2011 (LGM2011) resolves the gravity field of the Moon down to spatial scales of ~1.5 km.
Data
- LGM2011 surface gravity accelerations (SGM100i spectral band 2 to 70 gravity disturbances + LRTM70 gravity + LGM2011 normal gravity), unit in 10-5 ms-2. Note: a constant value of 162468 x 10-5 ms-2 must be added to this data set.
Download - LGM2011 free-air gravity anomalies (SGM100i spectral band 2 to 70 gravity disturbances + LRTM70 gravity) unit 10-5 ms-2.
Download - LGM2011 selenoid undulations (SGM100i spectral band 2 to 70 selenoid undulations, plus LRTM70 selenoid), unit is 10-1 m.
Download - LGM2011 North-South surface vertical deflection (SGM100i spectral band 2 to 70 + LRTM70 NS vertical deflection), unit is seconds of arc.
Download - LGM2011 East-West surface vertical deflection (SGM100i spectral band 2 to 70 + LRTM70 EW vertical deflection), unit is seconds of arc.
Download - LRTM70 gravity accelerations, unit 10-5 ms-2.
Download - LRTM70 selenoid undulations, unit 10-1 m.
Download - LRTM70 NS vertical deflection, unit seconds of arc.
Download - LRTM70 EW vertical deflection, unit seconds of arc.
Download - LGM2011 normal gravity, unit 10-5 ms-2. Note: a constant value of 162468 x 10-5 ms-2 must be added to this data set.
Download - SGM100i gravity disturbances (SGM100i spectral band 2 to 70, evaluated at the LOLA topography), unit 10-5 ms-2.
Download - SGM100i selenoid undulations (SGM100i spectral band 2 to 70, evaluated at a constant radius of R = 1738000 m), unit 10-1 m.
Download - SGM100i NS vertical deflection (SGM100i spectral band 2 to 70, evaluated at the LOLA topography), unit seconds of arc.
Download - SGM100i EW vertical deflection (SGM100i spectral band 2 to 70, evaluated at the LOLA topography), unit seconds of arc.
Download - Matlab-script to access LGM2011 data files
Download
Mars Gravity Model 2011 (MGM2011) resolves Mars’s gravity field down to ~ 3km.
Data
- MGM2011 surface gravity accelerations (computed as MRO110B2 spectral band 2 to 85 gravity disturbances + MRTM85 gravity + MGM2011 normal gravity), unit in 10-5 ms-2. Note: a constant value of 370000 x 10-5 ms-2 must be added to this data set.
Download - LGM surface gravity Minus 162468 Unit MGM2011 free-air gravity(MRO110B2 spectral band 2 to 85 gravity disturbances + MRTM85 gravity) unit 10-5 ms-2.
Download - LGM surface gravity Minus 162468 Unit MGM2011 North-South surface vertical deflection (MRO110B2 spectral band 2 to 85 + MRTM85 NS vertical deflection), unit is seconds of arc.
Download - LGM surface gravity Minus 162468 Unit MGM2011 East-West surface vertical deflection (MRO110B2 spectral band 2 to 85 + MRTM85 EW vertical deflection), unit is seconds of arc.
Download - MRTM85 gravity accelerations, unit 10-5 ms-2.
Download - LGM surface gravity Minus 162468 Unit MRTM85 areoid undulations, unit 10-1 m. This file can be used to augment the Mars areoid from space-craft data beyond spherical-harmonic degree 85.
Download - LGM surface gravity Minus 162468 Unit MRTM85 NS vertical deflection, unit seconds of arc.
Download - LGM surface gravity Minus 162468 Unit MRTM85 EW vertical deflection, unit seconds of arc.
Download - MGM2011 normal gravity, unit 10-5 ms-2. Note: a constant value of 370000 x 10-5 ms-2 must be added to this data set.
Download - MRO110B2 gravity disturbances (MRO110B2 spectral band 2 to 85, evaluated at the MOLA topography), unit 10-5 ms-2.
Download - LGM surface gravity Minus 162468 Unit MRO110B2 NS vertical deflection (MRO110B2 spectral band 2 to 85, evaluated at the MOLA topography), unit seconds of arc.
Download - LGM surface gravity Minus 162468 Unit MRO110B2 EW vertical deflection (MRO110B2 spectral band 2 to 85, evaluated at the MOLA topography), unit seconds of arc.
Download - Matlab-script to access MGM2011 data files
Download
LGM2011 and MGM2011 are composite models that refine existing gravity models from spacecraft-tracking data with high-resolution topography models. Topography from laser altimetry is used to compute the high-frequency gravity field constituents that cannot be sensed by spacecraft tracking. Newton’s law of gravitation reveals the fine structure of many impact craters and other medium and small-scale features. LGM2011 and MGM2011 provide surface gravity accelerations, surface vertical deflections, and free-air gravity as key products. Our models substantially improve upon the resolution of previous gravity field models for Moon and Mars by a factor of up to ~40.
MGM2011 helped NASA in analysing the landing phase of the world-famous Mars curiosity rover mission by diagnosing an anomaly observed in-flight. Band-limited Bouguer gravity derived from LGM2011 has been analysed over the complete surface of the moon revealing the location of 280 candidates for new basins/craters that have not been identified when using full-spectrum gravity or topography alone. Of the 280 basins identified, 66 are classified as distinct making them worthy of further investigation.
Contributors
- Dr Christian Hirt
- Dr Sten Claessens
- Prof William Featherstone
- Associate Professor Michael Kuhn