James Williams: 2005 Brouwer Award Winner
The winner of the 2005 Brouwer Award is James Williams (JPL), for his many
outstanding contributions to celestial mechanics. Perhaps the best
practitioner of ultra-precise celestial mechanics in the world, Williams
has used lunar laser ranging, now accurate to about 2 cm, to measure a 0.2
arcsec offset of the average position of the lunar spin axis from the
Cassini state. This offset is indicative of the dissipative processes
in the Moon's interior and led to the discovery that the Moon has a small
molten liquid core. Williams's work has also been instrumental in placing
limits upon the possible time variations of the gravitational constant and
other general relativistic parameters. Early in his career, he helped
pioneer the study of asteroid evolution by developing proper orbital
elements and then applying them to establish a number of dynamical asteroid
families.
You can view the presentation which Dr. Williams gave on June 27, 2006 at the
2006 AAS/DDA meeting in Halifax, Nova Scotia,
entitled, "Lunar Laser Ranging and the Evolution of Lunar Dynamics," as a
2.44 megabyte PDF file.
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