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Updated: Jan 30, 2026

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Mimicking a Space Mission to Mars Using Hindlimb Unloading and Partial Weight Bearing in Rats
Published on: April 4, 2019
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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.
Summary
Curiosity rover
Area of Science:
- Planetary Science
- Geophysics
- Mars Exploration
Background:
- Gravimetry precisely measures gravitational fields, aiding internal structure studies of planets.
- The Curiosity rover on Mars has accelerometers for navigation and attitude determination.
Purpose of the Study:
- To recalibrate Curiosity's accelerometers to measure gravitational acceleration changes.
- To infer subsurface rock density in Gale crater using gravimetry.
Main Methods:
- Recalibration of rover accelerometers to detect gravitational field variations.
- Measuring the decrease in gravitational field strength with elevation during rover ascent.
Main Results:
- The sedimentary rocks in Gale crater have a density of 1680 ± 180 kg/m³.
- This density is lower than anticipated, suggesting high porosity.
Conclusions:
- The inferred low rock density indicates significant porosity in Gale crater's sedimentary rocks.
- This finding constrains the maximum historical burial depths of these Martian rocks.
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