A5077786375- Astro and Planetary Science
- Planetary Science and Exploration
- Geological and Geochemical Analysis
- High-pressure geophysics and materials
- Space Exploration and Technology
- earthquake and tectonic studies
- Space Science and Extraterrestrial Life
- Geomagnetism and Paleomagnetism Studies
- Stellar, planetary, and galactic studies
- Geology and Paleoclimatology Research
- Spacecraft and Cryogenic Technologies
- Geophysics and Gravity Measurements
- Space exploration and regulation
- Solar and Space Plasma Dynamics
- Hydrocarbon exploration and reservoir analysis
- Marine and environmental studies
- Spacecraft Design and Technology
- Methane Hydrates and Related Phenomena
- Spacecraft Dynamics and Control
- Geological Studies and Exploration
- Geochemistry and Elemental Analysis
- Astronomy and Astrophysical Research
- History and Developments in Astronomy
- Scientific Research and Discoveries
- BIM and Construction Integration
Nantes Université
2004-2024
Centre National de la Recherche Scientifique
2012-2024
Le Mans Université
2022-2024
Laboratoire de Planétologie et Géosciences
2011-2024
Université Nantes Angers Le Mans
2011-2024
Université d'Angers
2022-2023
Institut des Sciences de la Terre
2018
Université Gustave Eiffel
2018
Université Grenoble Alpes
2018
Université Joseph Fourier
2002
Abstract As a prospective study for future exploration of Venus, we compute the tidal response Venus' interior assuming various mantle compositions and temperature profiles representative different scenarios formation evolution. The density seismic velocities are modeled from thermodynamical equilibria minerals used to predict moment inertia, Love numbers, tide‐induced phase lag characterizing signature internal structure in gravity field. viscoelasticity is parameterized using an Andrade...
A numerical model of two‐dimensional Rayleigh‐Bénard convection is used to study the relationship between surface heat flow (or Nusselt number) and viscosity at base lithosphere. Newtonian or non‐Newtonian, temperature‐ pressure‐dependent rheologies are considered. In high Rayleigh number time‐dependent regime, calculations yield Nu ∝ Ra BL 1/3 b eff −4/3 where effective dependence with temperature upper thermal boundary layer calculated ν viscosity) layer. The same for non‐Newtonian if...
Abstract The habitability of Europa's subsurface ocean is conditioned by heat released from the deep interior and intensity magmatic activity. Here, we investigate melting silicate mantle through time its consequences for seafloor magmatism modeling internal production transfer using a three‐dimensional numerical model. We show that melt can be produced during most history due to limited efficiency cooling thermal convection presence radiogenic heating. rate amplified tidal friction,...
Abstract Venus is the planet in Solar System most similar to Earth terms of size and (probably) bulk composition. Until mid-20th century, scientists thought that was a verdant world—inspiring science-fictional stories heroes battling megafauna sprawling jungles. At start Space Age, people learned actually has hellish surface, baked by greenhouse effect under thick, CO 2 -rich atmosphere. In popular culture, demoted from jungly playground (at best) metaphor for redemptive potential extreme...
We present a new numerical method to describe the internal dynamics of planetary mantles through coupling dynamic model with prediction geoid and surface topography. Our tool is based on simulation thermal convection variable viscosity in spherical shell finite-volume formulation. The grid mesh ‘cubed sphere’ technique that divides into six identical blocks. An investigation various advection schemes proposed: we opted for high-resolution, flux-limiter method. Benchmarks are then presented...
With the discovery of TRAPPIST-1 and its seven planets residing within 0.06 au, it is becoming increasingly necessary to carry out correct treatments tidal interactions. The eccentricity, rotation, obliquity do indeed result from evolution over lifetime system. Tidal interactions can also lead heating in interior (as for Io), which may then be responsible volcanism or surface deformation. In majority studies aimed at estimating rotation close-in their heating, are considered as homogeneous...
Radio occultation measurements at Venus have provided invaluable insights into the planet's atmospheric properties. One particularly intriguing phenomenon observed during these is radio scintillations, characterized by rapid fluctuations in signal intensity. scintillations are caused small-scale irregularities refractive index associated with variations of density. A possible source density vertical propagating internal gravity waves, which originate convective layer between about 50 and 55...
In the Antarctic Zone (AZ), deep nutrient-rich waters ascend to surface, feeding Southern Ocean's overturning circulation cells. However, rate of upwelling exceeds capacity phytoplankton fully consume gross nutrient supply AZ leading release previously sequestered CO2 into atmosphere. During ice ages, enhanced utilization has been proposed as a mechanism that could contribute lower atmospheric concentration. Fossil-bound δ15N records in point more complete nitrate consumption...
The amount of detected planets with sizes comparable to that the Earth is increasing drastically. Most Earth-size planet candidates orbit at close distances from their central star, and therefore are subjected large tidal forces. Accurate determination parameters exoplanets taking into account interior structure rheology essential better constrain rotational orbital history, hence impact on climate stability planetary habitability. In present study, we compute response rocky ice-rich solid...
The Venusian geological features are poorly gravity-resolved, and the state of core is not well constrained, preventing an understanding Venus’ cooling history. EnVision candidate mission to ESA’s Cosmic Vision Programme consists a low-altitude orbiter investigate atmospheric processes. gravity experiment aboard this aims determine geophysical parameters fully characterize its internal structure. By analyzing radio-tracking data that will be acquired through daily operations over six days...
The main characteristic of Venus that distinguishes it from the other planets is its rotation period, which very long at 243 Earth days. Although several solutions this period have been determined using different methods (either Venus’s orbit or Earth), parameter remains poorly constrained. In particular, there a difference 7 minutes between lowest and highest estimates period. Currently, only 3 minute variation in Length Of Day (LOD) can be explained by modeling various effects...
Numerical simulations of 2-D Rayleigh—Bénard convection are designed to study the development at base cooling lithosphere. A zero temperature is suddenly imposed mantle surface, which has initially a homogeneous temperature. The strongly temperature-dependent viscosity fluid heated from within, in order balance internal drift resulting global cooling. For while, lithosphere cools approximatively as conductive half-space and lithospheric isotherms depth grows square root age. As instabilities...
In the absence of seismological measurements, observations topography and gravity fields solid planets are primary constraints on their internal structure. To compute synthetic geoid induced by dynamics planetary interiors, we introduce a 3-D numerical tool describing mantle convection beneath an elastic lithosphere. Although energy conservation is treated in whole spherical domain, deformation aspect solved using hybrid technique (finite volume method for viscous flow, spectral...
EnVision is ESA’s next mission to Venus, in partnership with NASA, where NASA provides the Synthetic Aperture Radar payload and support. The ESA adoption scheduled for January 2024, launch 2031. start of science operations at Venus early 2035 following cruise, aerobraking phase around achieve a low polar orbit. scientific objective provide holistic view planet from its inner core upper atmosphere, studying planets history, activity climate. aims establish nature current state...
Context. Io’s spectacular activity is driven by tidal dissipation within its interior, which may undergo a large amount of melting. While models planetary interiors classically assume that anelastic associated only with shear deformation, seismological observation the Earth has revealed bulk might be important in case partial Aims. Although partially molten layer mantle been widely studied order to explain abnormally high heat flux, never included. The aim this study investigate role melt...
If Venus were a newly discovered exoplanet, it would be one of the most Earth-like yet identified. Its similarity in size, bulk density and cloud top temperatures give no clue to hellish at its surface. hosts an array geological features as complex Earth, but without organisation, sustains chemically reactive atmosphere, life. Proposed response ESA’s M5 call, with enabling support from NASA, EnVision is currently Phase A study for next medium-class mission opportunity proceeding...
A continuous kinematic model of present-day plate motions is developed which (1) provides more realistic models shapes than employed in the original work Bercovici & Wessel (1994), and (2) a means whereby geophysical data on intraplate deformation used to estimate plate-margin widths for all plates. given plate's shape function (which unity within zero outside plate) can be represented by analytic functions as long distance from point inside boundary expressed single-valued azimuth (i.e....
We perform three‐dimensional (3‐D) numerical simulations of an oceanic lithosphere cooling above a convective mantle to investigate flow geometry and its associated lithospheric features. A constant horizontal velocity (half spreading velocity) 2 (or 4) cm/yr is applied at the box surface mimic plate motion. In all cases, because temperature‐dependent viscosity, rigid conductive cools progressively beneath two plates separated by ridge. After 16–40 Ma, cold downgoing instabilities develop...