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Updated: Jan 30, 2026

Mimicking a Space Mission to Mars Using Hindlimb Unloading and Partial Weight Bearing in Rats
Published on: April 4, 2019
A surface gravity traverse on Mars indicates low bedrock density at Gale crater
Kevin W Lewis1, Stephen Peters2, Kurt Gonter2
1Earth and Planetary Sciences Department, Johns Hopkins University, Baltimore, MD 21218, USA. klewis@jhu.edu.
Abstract:
Gravimetry, the precise measurement of gravitational fields, can be used to probe the internal structure of Earth and other planets. The Curiosity rover on Mars carries accelerometers normally used for navigation and attitude determination. We have recalibrated them to isolate the signature of the changing gravitational acceleration as the rover climbs through Gale crater. The subsurface rock density is inferred from the measured decrease in gravitational field strength with elevation. The density of the sedimentary rocks in Gale crater is 1680 ± 180 kilograms per cubic meter. This value is lower than expected, indicating a high porosity and constraining maximum burial depths of the rocks over their history.
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