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| Titel |
Tidal constraints on the interior of Venus |
| VerfasserIn |
Caroline Dumoulin, Gabriel Tobie, Olivier Verhoeven, Pascal Rosenblatt, Nicolas Rambaux |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250148511
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| Publikation (Nr.) |
 EGU/EGU2017-12774.pdf |
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| Zusammenfassung |
| As a prospective study for a future exploration of Venus, we compute the tidal response of
Venus’ interior assuming various mantle compositions and temperature profiles
representative of different scenarios of Venus’ formation and evolution. The mantle
density and seismic velocities are modeled from thermodynamical equilibria of
mantle minerals and used to predict the moment of inertia, Love numbers and tidal
lag characterizing the signature of the internal structure in the gravity field. The
viscoelasticity of the mantle is parameterized using an Andrade rheology. From the
models considered here, the moment of inertia lies in the range of 0.327 to 0.342,
corresponding to a core radius of 2900 to 3450 km. The potential Love number,
k2, varies from 0.25 to 0.36. Viscoelasticity of the mantle strongly increases the
Love number relative to previous elastic models : depending on mantle viscosity,
k2 is increased by up to 25% using a liquid core. Moreover, once a viscoelastic
rheology is assumed for the core, our calculations show that the estimation of k2 from
tracking of Magellan and Pioneer Venus Orbiter does not rule out the possibility
of a completely solid core. Except if the solid core has a high viscosity (≥ 1018
Pa.s), solutions with both liquid and solid cores are consistent with the present-day
estimation of k2. More accurate estimation of the Love number together with estimation
of tidal lag by future exploration mission are required to determine the state of
Venus’ core and to constrain the thermo-compositional evolution of the mantle. |
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