Glacial isostatic adjustment reveals Mars’s interior viscosity structure DOI Creative Commons
A. Broquet, Ana‐Catalina Plesa, Volker Klemann

et al.

Nature, Journal Year: 2025, Volume and Issue: 639(8053), P. 109 - 113

Published: Feb. 26, 2025

Investigating glacial isostatic adjustment has been the standard method to decipher Earth's interior viscosity structure1,2, but such an approach rarely applied other planets because of a lack observational data3,4. The north polar cap Mars is only millions-of-years-old surface feature that can induce measurable deformation on this planet, thereby holding clues its present-day internal structure5,6. Here we investigate emplacement ice by combining thermal evolution models7, viscoelastic calculations8 and radar observations6. We show downward motion northern regions ongoing be constrained analyses time-variable gravity field9 NASA's InSight seismic moment rate10. Only models with high viscosities (2-6 × 1022 Pa s for depths greater than 500 km), strong mantle depletion in radiogenic elements (more 90%) thick average crusts (thicker 40 km) are consistent negligible flexure beneath seen radars. lithosphere must deform at less 0.13 mm per year have efficiency 0.3 satisfy constraints, respectively. Our formed over last 1.7-12.0 Myr further future recovery missions Mars11,12.

Language: Английский

THUNDER: A Titan Orbiter Mission Concept for the New Frontiers Program Designed at the JPL Planetary Science Summer School DOI Creative Commons
Cassandra Seltzer, Rudi Lien, Brandon T. Radzom

et al.

The Planetary Science Journal, Journal Year: 2025, Volume and Issue: 6(2), P. 45 - 45

Published: Feb. 1, 2025

Abstract Saturn's moon Titan is an enigmatic icy world whose surface constantly modified by its active, Earthlike precipitation system. Here, we propose the Titan's Hydrocarbons: Uncovering New Dimensions of Evolutionary pRocesses (THUNDER) mission concept to investigate how reflects nature interior and active hydrocarbon cycle. This will change our understanding through three science objectives: characterizing heat material transport properties outer layer, tracing liquid storage across crust, assessing total budget time. Frontiers-class mission, designed as part Jet Propulsion Laboratory Planetary Science Summer School, responds directly call for a orbiter in NASA Astrobiology Decadal Survey 2023–2032. THUNDER's focused geology geophysics could achieve full mapping complement both Cassini–Huygens Dragonfly missions using gravity science, radar with operational modes, visible-to-infrared spectrometer. These instruments together give us first look at fully connected geologically world, revolutionizing bodies, fluvial atmospheric processes, habitability geologic summarize goals engineering approaches, well challenges future directions study before THUNDER can become viable concept.

Language: Английский

Citations

0
Glacial isostatic adjustment reveals Mars’s interior viscosity structure DOI Creative Commons
A. Broquet, Ana‐Catalina Plesa, Volker Klemann

et al.

Nature, Journal Year: 2025, Volume and Issue: 639(8053), P. 109 - 113

Published: Feb. 26, 2025

Investigating glacial isostatic adjustment has been the standard method to decipher Earth's interior viscosity structure1,2, but such an approach rarely applied other planets because of a lack observational data3,4. The north polar cap Mars is only millions-of-years-old surface feature that can induce measurable deformation on this planet, thereby holding clues its present-day internal structure5,6. Here we investigate emplacement ice by combining thermal evolution models7, viscoelastic calculations8 and radar observations6. We show downward motion northern regions ongoing be constrained analyses time-variable gravity field9 NASA's InSight seismic moment rate10. Only models with high viscosities (2-6 × 1022 Pa s for depths greater than 500 km), strong mantle depletion in radiogenic elements (more 90%) thick average crusts (thicker 40 km) are consistent negligible flexure beneath seen radars. lithosphere must deform at less 0.13 mm per year have efficiency 0.3 satisfy constraints, respectively. Our formed over last 1.7-12.0 Myr further future recovery missions Mars11,12.

Language: Английский

Citations

0