The end of the lunar dynamo.
Ontology highlight
ABSTRACT:
SUBMITTER: Mighani S
PROVIDER: S-EPMC6938704 | biostudies-literature | 2020 Jan
REPOSITORIES: biostudies-literature
Publications
The end of the lunar dynamo.
Mighani Saied S Wang Huapei H Shuster David L DL Borlina Cauȇ S CS Nichols Claire I O CIO Weiss Benjamin P BP
Science advances 20200101 1
Magnetic measurements of the lunar crust and Apollo samples indicate that the Moon generated a dynamo magnetic field lasting from at least 4.2 until <2.5 billion years (Ga) ago. However, it has been unclear when the dynamo ceased. Here, we report paleomagnetic and <sup>40</sup>Ar/<sup>39</sup>Ar studies showing that two lunar breccias cooled in a near-zero magnetic field (<0.1 μT) at 0.44 ± 0.01 and 0.91 ± 0.11 Ga ago, respectively. Combined with previous paleointensity estimates, this indicates ...[more]
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