Paleomagnetism of the moon and the problem of planetary dynamo fields
It is shown within the scope of the precessional dynamo model that satellites of the moon, which, as has been proposed, existed in equatorial orbits 4-3.8 Gyr ago and whose fall to the surface relates to the formation of the maria (14) and a change in position of the axis of rotation of the moon (15), could have determined the generation of a strong dynamo field of 10/sup -4/ T in which the ancient lunar rocks acquired thermoremanent magnetization. The strong dynamo field attenuated with the fall of the satellites to the surface of the moon, but a moderate dynamo field could have been generated with the precession of the moon under the perturbing effect of the gravitational field of the earth. This field also attenuated with the recession of the moon from the earth and its acquisition of synchronous rotation. If the distribution of the paleofields over the entire surface of the moon, which one can hope will be established, confirms the assumption of uniform magnetization of the lunar crest by a field of internal origin, then the planetary precessional dynamo model gets additional proof of the established cause-effect relation: If the source inducing the precessional motion disappears, then the magnetic field disappears.
- OSTI ID:
- 7021044
- Journal Information:
- Cosmic Res. (Engl. Transl.); (United States), Journal Name: Cosmic Res. (Engl. Transl.); (United States) Vol. 24:1; ISSN CSCRA
- Country of Publication:
- United States
- Language:
- English
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