An internally generated magnetic field once existed on the Moon. This field reached high intensities (∼10–100
Absence of a long-lived lunar paleomagnetosphere
Determining the presence or absence of a past long-lived lunar magnetic field is crucial for understanding how the Moon’s interior and surface evolved. Here, we show that Apollo impact glass associated with a young 2 million–year–old crater records a strong Earth-like magnetization, providing evidence that impacts can impart intense signals to samples recovered from the Moon and other planetary bodies. Moreover, we show that silicate crystals bearing magnetic inclusions from Apollo samples formed at ∼3.9, 3.6, 3.3, and 3.2 billion years ago are capable of recording strong core dynamo–like fields but do not. Together, these data indicate that the Moon did not have a long-lived core dynamo. As a result, the Moon was not sheltered by a sustained paleomagnetosphere, and the lunar regolith should hold buried 3 He, water, and other volatile resources acquired from solar winds and Earth’s magnetosphere over some 4 billion years.
- Publication Date:
- NSF-PAR ID:
- 10316305
- Journal Name:
- Science Advances
- Volume:
- 7
- Issue:
- 32
- ISSN:
- 2375-2548
- Sponsoring Org:
- National Science Foundation
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- https://doi.org/10.1126/sciadv.abi7647
