HR: 0800h
AN: P51B-0487 [Abstracts]
TI: A Small Geodesy Surface Package for Future Lunar Robotic Missions
AU: * Oberst, J
EM: Juergen.Oberst@dlr.de
AF: German Aerospace Center, Institute of Planetary Research, Rutherfordstr. 2, Berlin, 12489,
Germany
AU: Schreiber, U
EM: schreiber@wettzell.ifag.de
AF: Technical University Munich and Geodetic Observatory Wettzell, Sackenrieder Str. 25,
Kötzting, 93444, Germany
AU: Müller, J
EM: mueller@ife.uni-hannover.de
AF: Leibniz University of Hannover, Institute of Geodesy, Schneiderberg 50, Hannover, 30167,
Germany
AU: Nothnagel, A
EM: nothnagel@uni-bonn.de
AF: University of Bonn, Institute of Geodesy and Geoinformation, Nussallee 17, Bonn, 53115,
Germany
AU: Hugentobler, U
EM: urs.hugentobler@bv.tu-muenchen.de
AF: Technical University Munich and Geodetic Observatory Wettzell, Sackenrieder Str. 25,
Kötzting, 93444, Germany
AU: Michaelis, H
EM: Harald.Michaelis@dlr.de
AF: German Aerospace Center, Institute of Planetary Research, Rutherfordstr. 2, Berlin, 12489,
Germany
AB:
We propose to deploy small (2-3 kg) Lunar geodesy packages on the Moon's surface, consisting of an optical
Laser receiver, a small retroreflector, as well as a radio beacon. The optical receiver will maintain Earth pointing
through the Lunar libration cycles and record arrival times of Laser shots from Earth. Judging from the photon
budget for a 50 mJ pulse Laser, most of the existing more than 30 ILRS (International Laser Ranging Service)
stations could participate in the experiment and produce large numbers of range measurements at high accuracy
and unbiased temporal coverage. The light-weight 0.5 sqm retroreflector will be adequate for direct ranging
measurements using the classic Lunar Laser Ranging stations. The simultaneous acquisition of data from the
Laser receiver on the Moon and reflected Laser shots on Earth will allow us to calibrate the onboard clock. A
small radio source shall be deployed within the package, for tracking by VLBI stations. The experience from the
past 38 years of Apollo Lunar Laser Ranging suggests that there is enormous science potential in ranging data
to further our understanding of the Moon's internal structure, the dynamics of the Earth-Moon system and
fundamental physics. For example, from the Moon's tidal response, inferences can be made on a solid or liquid
Lunar core and its size and oblateness. In addition, parameters from gravitational physics, e.g., the time-stability
of the gravitational "constant", or the strong equivalence principle (Nordtvedt-effect) could be modeled with vastly
improved accuracy. While the position of the Laser receiver will define an important anchor point in the lunar-fixed
coordinate system, the radio transmitter will firmly tie the dynamical reference frame of the Lunar orbit into the
quasi-inertial kinematic reference frame of Quasar coordinates for insights into the Moon's orbital behavior to as
yet unknown frontiers.
DE: 6024 Interiors (8147)
DE: 6035 Orbital and rotational dynamics
DE: 6250 Moon (1221)
DE: 6297 Instruments and techniques
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting