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The Orientation of the Dynamical Reference Frame

Published online by Cambridge University Press:  12 April 2016

J.G. Williams
Affiliation:
Jet Propulsion LaboratoryCalifornia Institute ofTechnologyPasadena, CA 91109-8099USA
J.O. Dickey
Affiliation:
Jet Propulsion LaboratoryCalifornia Institute ofTechnologyPasadena, CA 91109-8099USA
X X Newhall
Affiliation:
Jet Propulsion LaboratoryCalifornia Institute ofTechnologyPasadena, CA 91109-8099USA
E.M. Standish
Affiliation:
Jet Propulsion LaboratoryCalifornia Institute ofTechnologyPasadena, CA 91109-8099USA

Abstract

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We summarize the current status of the JPL ephemerides, focusing on the various data types utilized, especially the impact of the modern ranging data, and the resulting accuracies obtained. The dynamical equinox, as determined from the analysis of Lunar Laser Ranging data, is determined with an accuracy of 5 mas and the obliquity to a 2 mas level in ~1983, the weighted center of data. Knowledge of the lunar and planetary positions with respect to the dynamical equinox degrades to 10 mas at J2000. Twenty years of LLR data allow for the separation of the 18.6 yr nutation terms from the precession constant. The correction to IAU precession is found to be −2.7 ± 0.4 mas/yr, while the 18.6 yr nutation of the pole is 3.0 ± 1.5 mas larger in magnitude than the 1980 IAU series. The necessity of different reference systems and the accurate knowledge of the interconnections between frames is addressed.

Type
Part 1. Oral Papers
Copyright
Copyright © United States Naval Observatory 1991

References

Chapront-Touzé, M. and Chapront, J., The lunar ephemeris ELP2000, Astron. Astrophys., 124, 5062, 1983.Google Scholar
Charlot, P., Sovers, O.J., Williams, J.G., and Newhall, X X, A Global VLBI/LLR Analysis for the Determination of Precession and Nutation Constants, this volume.Google Scholar
Dickey, J.O., Intercomparisons Between Kinematic and Dynamical Systems, in Reference Frames (Kovelevsky, J., Mueller, I.I. and Kolaczek, B., eds.) Kluwer Academic Publishers, Dordrecht, 305326, 1989.Google Scholar
Herring, T.A., Buffett, B.A., Matthews, P.M., and Shapiro, I.I., J. Geophys. Res., in press, 1990.Google Scholar
Kinoshita, H. and Souchay, J., Celes. Mech., in press, 1990.Google Scholar
Lieske, J.H., Lederle, T., Fricke, W., and Morando, B., Astron. Astrophys., 58, 1, 1977.Google Scholar
Seidelmann, P.K., Celes. Mech., 27, 7, 1982.CrossRefGoogle Scholar
Standish, E.M., The JPL Planetary Ephemerides, Cel. Mech. J., 26, 181186, 1982.Google Scholar
Standish, E.M., The observational basis for JPL’s DE200, the planetary ephemerides of the Astronomical Almanac, Astron. Astrophys., 233, #1, 252271, 1990.Google Scholar
Standish, E.M. and Williams, J.G., Dynamical Reference Frame in the Planetary and Earth-Moon Systems, in Inertial Coordinate System on the Sky (Lieske, J..H. and Abalakin, V.K., eds.) Kluwer Academic Publishers, Dordrecht, 173181, 1990.Google Scholar
Standish, E.M., Orientation of the JPL Ephemerides, DE200/LE200, to the Dynamical Equinox of J2000, Astron. Astrophys., 114, 297302, 1982.Google Scholar
Wahr, J.M. and Sasao, T., Geophys. J. Royal Astron. Soc., 64, 747, 1981.CrossRefGoogle Scholar
Williams, J.G. and Standish, E.M., Dynamical Reference Frames in the Planetary and Earth-Moon Systems, in Reference Frames (Kovalevsky, J., Mueller, I.I. and Kolaczek, B., eds.) Kluwer Academic Publishers, Dordrecht, 6790, 1989.Google Scholar
Williams, J.G., Newhall, X X, Dickey, J.O., Luni-solar Precession: Determination from Lunar Laser Ranging, Astron. Astrophys. Lett., in press, 1990.Google Scholar
Zhu, S.Y., Groten, E., and Reigber, C., Astron. J., 99, 1024, 1990.Google Scholar