HR: 1340h
AN: G43A-0794    [Abstracts]
TI: Regional Gravity From Lunar Prospector Extended Mission Data: Results for Copernicus and Serenitatis
AU: Goossens, S
EM: sander@deos.tudelft.nl
AF: Astrodynamics and Satellite Systems, Department of Earth Observation and Space Systems, Delft University of Technology, Kluyverweg 1, Delft, 2629 HS Netherlands
AU: Goossens, S
EM: sander@deos.tudelft.nl
AF: National Astronomical Observatory, Division of Earth Rotation, 2-12 Hoshigaoka, Mizusawa, 023-0861 Japan
AU: Visser, P
EM: pieter.visser@lr.tudelft.nl
AF: Astrodynamics and Satellite Systems, Department of Earth Observation and Space Systems, Delft University of Technology, Kluyverweg 1, Delft, 2629 HS Netherlands
AU: * Heki, K
EM: heki@ep.sci.hokudai.ac.jp
AF: Division of Earth and Planetary Sciences, Hokkaido University, Kita-ku, N10 W8, Sapporo, 060-0810 Japan
AU: Ambrosius, B
EM: b.a.c.ambrosius@lr.tudelft.nl
AF: Astrodynamics and Satellite Systems, Department of Earth Observation and Space Systems, Delft University of Technology, Kluyverweg 1, Delft, 2629 HS Netherlands
AB: In the past ten years, the Moon has come fully back into focus again. This resulted in missions such as Clementine (launched in 1994) and Lunar Prospector (1998), which gathered a wealth of new information about the Moon. With the recent launch of Europe's SMART-1 mission, and the foreseen launch in the near future of Lunar-A and SELENE, together with intended initiatives by China, India and the USA, the list of lunar missions is expanded even further, and more issues about the constitution and origin of the Moon, to name a few, will be addressed. Our work focuses on processing Lunar Prospector data in order to create high resolution regional gravity fields of the Moon, that can help solve some of the outstanding issues in lunar physics. Lunar gravity has been mainly expressed in a global representation, despite the lack of tracking data over the far side of the Moon. To extract all information about the near side of the Moon, which is covered well with good quality tracking data, a global formulation is not efficient, and regional representations become of interest. A method is presented to solve for regional gravity anomalies on the lunar surface from range and Doppler tracking data residuals, at an aimed accuracy of several mGal. The method is based on a linear variational approach that linearises the relationship between the tracking data residuals and gravity anomalies. Even in the presence of severe noise of the data, it can be shown that an accuracy of 3 mGal can still be obtained without the use of regularisation, provided that the satellite altitude is low enough. Lunar Prospector tracking data have been processed for the extended mission part, which lasted from January 1999 until July 31, 1999. The data fit is typically better than 5 mm/s for Doppler data, and 3 m for range data. These data have been used in order to make solutions of regional gravity adjustments for crater Copernicus and Mare Serenitatis. Results from this work can also benefit future interpretation of SELENE data. Lunar Prospector data can now also be processed and combined with future SELENE data to solve for the lunar gravity field.
DE: 5417 Gravitational fields (1227)
DE: 1219 Local gravity anomalies and crustal structure
DE: 1221 Lunar geodesy and gravity (6250)
SC: Geodesy [G]
MN: 2004 AGU Fall Meeting