Mars precession rate determined from radiometric tracking of the InSight Lander

The Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport (InSight) mission has provided an opportunity to improve our knowledge of Mars' interior via the Rotation and Interior Structure Experiment (RISE). RISE provides information on the rotation of Mars by measuring the Doppler shift of radio transmissions from InSight to NASA's Deep Space Network (DSN) on Earth. Through the combination of one year of Doppler data from InSight with previous data from the Viking-1 lander, Mars Pathfinder, and Opportunity missions, data spanning 43 years from 1976 to 2019 are used to estimate the Mars precession rate as similar to 7605 +/- 3 milliarcseconds per year. This result is consistent with the precession rate estimated from Doppler tracking of previous landers and orbiters alone.

Automated summary

The InSight mission has improved understanding of Mars' interior through the RISE experiment, which measures the Doppler shift of radio transmissions to determine Mars' rotation. By analyzing data from multiple missions spanning 43 years, an estimate of Mars precession rate was obtained, consistent with previous estimates.