Book contents
- Frontmatter
- Contents
- Foreword
- Note on the expression of planetary masses
- 1 Introduction
- 2 The internal structure of the Earth
- 3 Methods for the determination of the dynamical properties of planets
- 4 Equations of state of terrestrial materials
- 5 The Moon
- 6 Mars, Venus and Mercury
- 7 High pressure metals
- 8 Jupiter and Saturn, Uranus and Neptune
- 9 Departures from the hydrostatic state
- 10 Conclusion
- Appendix 1 Limits and conditions on planetary models
- Appendix 2 Combination of effects of small departures from a uniform distribution of density
- Appendix 3 The physical librations of the Moon
- References
- Index
- Frontmatter
- Contents
- Foreword
- Note on the expression of planetary masses
- 1 Introduction
- 2 The internal structure of the Earth
- 3 Methods for the determination of the dynamical properties of planets
- 4 Equations of state of terrestrial materials
- 5 The Moon
- 6 Mars, Venus and Mercury
- 7 High pressure metals
- 8 Jupiter and Saturn, Uranus and Neptune
- 9 Departures from the hydrostatic state
- 10 Conclusion
- Appendix 1 Limits and conditions on planetary models
- Appendix 2 Combination of effects of small departures from a uniform distribution of density
- Appendix 3 The physical librations of the Moon
- References
- Index
Summary
Introduction
After the Earth, the Moon is much the best known body of the solar system. Almost all physical measurements that have been made on the Earth have also to some extent been made on the Moon. Artificial satellites have been placed in orbit about the Moon and have enabled the components of the gravitational potential to be estimated. The physical librations, the equivalent of the luni-solar precession of the Earth, have been observed, especially by laser ranging to the retroreflectors left on the Moon by Apollo astronauts. The Apollo astronauts took with them seismometers that have recorded impacts of meteorites and rockets on the surface and moonquakes within the Moon. The flow of heat through the surface of the Moon was measured.
The magnetic field of the Moon has been studied intensively, globally by satellites at a distance from the surface and in detail by others close to it, while the magnetization of rock samples brought back by the Apollo astronauts has been studied in the laboratory. In addition, electro-magnetic induction in the Moon has been studied. Thus, there is some prospect of being able to construct models of the interior of the Moon using much the same methods as are followed for the Earth, whereas there is at present no such prospect for any of the planets. However, there are major gaps in our knowledge of the Moon as compared with the Earth, and the principal one is that seismic data are comparatively very sparse because there are only four seismic stations on the Moon and all of them are on the same hemisphere and, furthermore, because free oscillations of the Moon have never been observed.
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- Interiors of the Planets , pp. 132 - 170Publisher: Cambridge University PressPrint publication year: 1980