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Magnetic dynamo in the moon: a comparison with the Earth
Science (New York, N.Y.)
|October 6, 1972
Summary
A lunar dynamo requires the Moon to spin faster than its breakup speed, challenging its role in generating the observed magnetic remanence. This suggests the Moon
Area of Science:
- Planetary Science
- Geophysics
Background:
- The Moon exhibits magnetic remanence, suggesting a past internal magnetic field.
- The Earth's geomagnetic field is generated by a dynamo process.
Purpose of the Study:
- To evaluate the tenability of a lunar dynamo as an explanation for the Moon's magnetic remanence.
Main Methods:
- Theoretical modeling of lunar rotation.
- Analysis of angular velocity limits for celestial bodies.
Main Results:
- A lunar dynamo, similar to Earth's, necessitates a rotation rate exceeding the Moon's structural integrity limit.
- This high rotation rate is physically implausible for the Moon.
Conclusions:
- A dynamo mechanism is unlikely to be the source of the Moon's observed magnetic remanence.
- Alternative explanations for lunar magnetism should be explored.
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