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gravity model improvement using geos 3 /gem 9 and 10/Although errors in previous gravity models have produced large uncertainties in the orbital position of GEOS 3, significant improvement has been obtained with new geopotential solutions, Goddard Earth Model (GEM) 9 and 10. The GEM 9 and 10 solutions for the potential coefficients and station coordinates are presented along with a discussion of the new techniques employed. Also presented and discussed are solutions for three fundamental geodetic reference parameters, viz. the mean radius of the earth, the gravitational constant, and mean equatorial gravity. Evaluation of the gravity field is examined together with evaluation of GEM 9 and 10 for orbit determination accuracy. The major objectives of GEM 9 and 10 are achieved. GEOS 3 orbital accuracies from these models are about 1 m in their radial components for 5-day arc lengths. Both models yield significantly improved results over GEM solutions when compared to surface gravimetry, Skylab and GEOS 3 altimetry, and highly accurate BE-C (Beacon Explorer-C) laser ranges. The new values of the parameters discussed are given.
Document ID
Document Type
Reprint (Version printed in journal)
Lerch, F. J.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Wagner, C. A.
(NASA Goddard Space Flight Center Geodynamics Branch, Greenbelt, Md., United States)
Klosko, S. M.
(EG & G Washington Analytical Services Center Inc., Riverdale, Md., United States)
Laubscher, R. E.
(Computer Sciences Corp. Silver Spring, Md., United States)
Date Acquired
August 9, 2013
Publication Date
July 30, 1979
Publication Information
Publication: Journal of Geophysical Research
Volume: 84
Subject Category
Distribution Limits