The gravitational field of Phobos
Abstract
The external gravitational field produced by a rigid body of uniform density but irregular shape is formulated in terms of spherical harmonics. The formalism is applied to the Martian satellite Phobos. Based on a 3dimensional shape model of Phobos by Duxbury, the gravitational coefficients up to degree and order 4 for a homogeneous Phobos are computed. In particular, the authors find J{sub 2} = 0.105. The inplane liberation amplitude of a homogeneous Phobos is predicted to be 0.97{degree}, within the rather large uncertainty of the observed value of 0.78 {plus minus} 0.4{degree}.
 Authors:
 (NASA Goddard Space Flight Center, Greenbelt, MD (USA))
 Publication Date:
 OSTI Identifier:
 5833124
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Geophysical Research Letters (American Geophysical Union); (USA); Journal Volume: 16:8
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; MARS PLANET; SATELLITES; GRAVITATIONAL FIELDS; CALCULATION METHODS; CARTESIAN COORDINATES; DENSITY; MORPHOLOGY; SPHERICAL HARMONICS; TOPOGRAPHY; COORDINATES; PHYSICAL PROPERTIES; PLANETS; 640107*  Astrophysics & Cosmology Planetary Phenomena
Citation Formats
Chao, B.F., and Rubincam, D.P. The gravitational field of Phobos. United States: N. p., 1989.
Web. doi:10.1029/GL016i008p00859.
Chao, B.F., & Rubincam, D.P. The gravitational field of Phobos. United States. doi:10.1029/GL016i008p00859.
Chao, B.F., and Rubincam, D.P. 1989.
"The gravitational field of Phobos". United States.
doi:10.1029/GL016i008p00859.
@article{osti_5833124,
title = {The gravitational field of Phobos},
author = {Chao, B.F. and Rubincam, D.P.},
abstractNote = {The external gravitational field produced by a rigid body of uniform density but irregular shape is formulated in terms of spherical harmonics. The formalism is applied to the Martian satellite Phobos. Based on a 3dimensional shape model of Phobos by Duxbury, the gravitational coefficients up to degree and order 4 for a homogeneous Phobos are computed. In particular, the authors find J{sub 2} = 0.105. The inplane liberation amplitude of a homogeneous Phobos is predicted to be 0.97{degree}, within the rather large uncertainty of the observed value of 0.78 {plus minus} 0.4{degree}.},
doi = {10.1029/GL016i008p00859},
journal = {Geophysical Research Letters (American Geophysical Union); (USA)},
number = ,
volume = 16:8,
place = {United States},
year = 1989,
month = 8
}
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