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Geodesy by radio interferometry: Studies of the forced nutations of the earth. I - Data analysis. II - InterpretationVery long baseline interferometry (VLBI) observations of compact extragalactic radio sources collected in North America and Europe between July 1980-December 1984 are analyzed. The nutations derived from VLBI data are compared with the nutations in the Wahr series (1981). Good correlation of the data is observed; however, it is detected that a correction of -1.80 + or - 0.18-i(0.42 + or - 0.18) is required for the amplitude of the retrograde annual nutation in the Wahr series. The change in free core nutation resonance frequency is calculated to explain the derivation in the retrograde annual nutation. It is concluded that VLBI earth nutation measurements have sufficient accuracy to be sensitive to core-mantle boundary properties.
Document ID
19860051354
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Herring, T. A.
(Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Gwinn, C. R.
(Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Shapiro, I. I.
(Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Date Acquired
August 12, 2013
Publication Date
April 10, 1986
Publication Information
Publication: Journal of Geophysical Research
Volume: 91
ISSN: 0148-0227
Subject Category
Geophysics
Accession Number
86A36092
Funding Number(s)
CONTRACT_GRANT: F19628-83-K-0031
CONTRACT_GRANT: NSF EAR-83-06380
CONTRACT_GRANT: NAS5-27571
CONTRACT_GRANT: NSF EAR-83-02221
Distribution Limits
Public
Copyright
Other

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