GRGM900C: A degree 900 lunar gravity model from GRAIL primary and extended mission data

• Published in: Geophysical research letters Vol. 41; no. 10; pp. 3382 - 3389
• Main Authors: Lemoine, Frank G., Goossens, Sander, Sabaka, Terence J., Nicholas, Joseph B., Mazarico, Erwan, Rowlands, David D., Loomis, Bryant D., Chinn, Douglas S., Neumann, Gregory A., Smith, David E., Zuber, Maria T.
• Format: Journal Article
• Language: English
• Published: Goddard Space Flight Center Blackwell Publishing Ltd 28.05.2014; AGU publications; John Wiley & Sons, Inc; BlackWell Publishing Ltd
• Subjects: Altitude; GRAIL; Gravitation; Gravity; KBRR data; Lunar And Planetary Science And Exploration; lunar gravity; Mathematical models; Moon; orbit determination; planetary geodesy; Polar environments; Polar regions; Research Letters; Space missions; Spherical harmonics; Strength; Tracking; Grail; Moon; Gravity
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1002/2014GL060027

We have derived a gravity field solution in spherical harmonics to degree and order 900, GRGM900C, from the tracking data of the Gravity Recovery and Interior Laboratory (GRAIL) Primary (1 March to 29 May 2012) and Extended Missions (30 August to 14 December 2012). A power law constraint of 3.6 × 10(exp −4)/l(exp 2) was applied only for degree l greater than 600. The model produces global correlations of gravity, and gravity predicted from lunar topography of greater than or equal to 0.98 through degree 638. The model's degree strength varies from a minimum of 575-675 over the central nearside and farside to 900 over the polar regions. The model fits the Extended Mission Ka-Band Range Rate data through 17 November 2012 at 0.13 micrometers/s RMS, whereas the last month of Ka-Band Range-Rate data obtained from altitudes of 2-10 km fit at 0.98 micrometers/s RMS, indicating that there is still signal inherent in the tracking data beyond degree 900.