InSight Pressure Data Recalibration, and Its Application to the Study of Long-Term Pressure Changes on Mars

Area of Science:

• Planetary Science
• Atmospheric Science
• Geophysics

Background:

• The South Polar Residual Cap's potential erosion could increase Mars' atmospheric mass.
• Previous studies have not directly compared long-term surface pressure data.

Purpose of the Study:

• To test the hypothesis of South Polar Residual Cap erosion by comparing historical and recent Martian pressure data.
• To assess changes in Martian seasonal ice cap dynamics over a 40-year period.

Main Methods:

• Recalibration of InSight pressure sensor data.
• Development of interpolation methods for comparing distant pressure measurements.
• Analysis of Viking, InSight, and Mars Science Laboratory (MSL) surface pressure data.

Main Results:

• No significant changes (±8 Pa) in the Martian CO2 cycle were detected between Viking and InSight data.
• Analysis of the south seasonal cap shows no significant dynamic changes over 40 years.
• A potential larger extension of the North Cap after a global storm was observed, but its cause is unclear.

Conclusions:

• The Martian CO2 cycle appears stable over the 40-year period studied.
• No evidence for significant South Polar Residual Cap erosion was found.
• A pressure deficit in Gale crater during southern summer may be linked to suspended dust.