Scientists have discovered that the liquid core of Mars is actually smaller and denser than previously believed. This discovery was made possible using data collected by the NASA lander Insight, which was able to measure the seismic waves of two earthquakes that occurred on the opposite side of the red planet in autumn of 2021. These waves penetrated deep into the interior of the planet, making it possible to obtain more precise data. It also corrected previous conclusions derived from data that was not as accurate.
The research group also found that around one-fifth of Mars’ core is comprised of sulfur, oxygen, carbon, and hydrogen. The study was led by Jessica Irving, from the University of Bristol, who stated that the analysis required both luck and skill, with luck being provided by the two marsquakes that hit the red planet on August 25 and September 18, 2021. The weak signals they generated were detected in the data only because of the experience gained from previous analysis.
Insight landed on Mars in November 2018, and over four years, utilized a sensitive seismometer to measure waves produced by subsurface earthquakes. The ultimate goal was to understand the planet’s interior, and the recent discovery has provided a new level of clarity. Aside from meteorite impacts, tremors in Mars’ crust are caused by stresses in the rock caused by the slow shrinking of the cooling planet since the “one-plate planet” does not have plate tectonics processes like those on Earth.
The results of the study have been published in the Proceedings of the National Academies of Sciences. Insight, the Mars probe itself, stopped working just before Christmas Eve in 2022 due to dust on its solar panels, which had accumulated and reduced the amount of power available. NASA had hoped a storm would clear the dust from the solar collectors, but unfortunately, the probe stopped functioning entirely. The probe only said farewell with one last picture.
