The tidal–rotational shape of the Moon and evidence for polar wander

  title={The tidal–rotational shape of the Moon and evidence for polar wander},
  author={I. Garrick-Bethell and V. Perera and F. Nimmo and M. Zuber},
The origin of the Moon’s large-scale topography is important for understanding lunar geology, lunar orbital evolution and the Moon’s orientation in the sky. Previous hypotheses for its origin have included late accretion events, large impacts, tidal effects and convection processes. However, testing these hypotheses and quantifying the Moon’s topography is complicated by the large basins that have formed since the crust crystallized. Here we estimate the large-scale lunar topography and gravity… Expand
Evidence for lunar true polar wander and a past low‐eccentricity, synchronous lunar orbit
As first noted 200 years ago by Laplace, the Moon's rotational and tidal bulges are significantly larger than expected, given the Moon's present orbital and rotational state. This excess deformationExpand
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First recognized by Laplace over two centuries ago, the Moon’s present tidal-rotational bulges are significantly larger than hydrostatic predictions. They are likely relics of a former hydrostaticExpand
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Lunar true polar wander inferred from polar hydrogen
The hypothesis that true polar wander was caused by a low-density thermal anomaly beneath the Procellarum region implies that polar wander initiated billions of years ago and that a large portion of the measured polar hydrogen is ancient, recording early delivery of water to the inner Solar System. Expand
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Tidal resonance of eigenmode oscillation in the early Earth's ocean and its acceleration effect on the Moon's orbital evolution
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[1] It is proposed that lunar crustal asymmetries are the result of convective processes acting early in the Moon's history, during the magma-ocean phase and after synchronous rotation wasExpand
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The lunar gravity field can be satisfactorily explained by relatively-small wavelength, density anomalies located near the lunar surface. The exceptions to this are the second degree harmonics and weExpand
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According to the authors' simulations, a large moon/Moon size ratio and a subsonic impact velocity lead to an accretionary pile rather than a crater, contributing a hemispheric layer of extent and thickness consistent with the dimensions of the farside highlands and in agreement with the degree-two crustal thickness profile. Expand
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[1] The Moon possesses a clear dichotomy in geological processes between the nearside and farside hemispheres. The most pronounced expressions of this dichotomy are the strong concentration ofExpand
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[1] Many regions near the lunar poles are currently cold enough that surface water ice would be stable against sublimation losses for billions of years. However, most of these environments areExpand
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Abstract The South Pole-Aitken basin (SP-A) is the largest and oldest basin on the Moon. The basin has usually been interpreted to exhibit a degraded circular structure, but here we demonstrate thatExpand
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