Seismic waves inside Mars' core hint at how it became hostile to life

Using the InSight lander scientists have measured seismic waves traveling through the core of Mars for the first time gathering clues as to why the Red Planet may not be fit for life.

Seismic waves inside Mars' core hint at how it became hostile to life : Read more

The article gets the Earth's solid inner and liquid outer core backwards.

"Our results are consistent with a core rich in sulfur, with smaller fractions of oxygen, carbon and hydrogen. ... our compositional inversions find that the Martian core contains a median of 20.3 to 21.4 wt% total light elements...."

They compare their Mars core work with other work that has estimated the size and composition of Earth and lunar cores. The lunar core is thought to have little Si and O, but more S and C. Earth's core is different, but perhaps not that different:

Earth’s liquid outer core is suggested to have only about half the fraction of light elements advocated for Mars’s core, as it is likely to contain less than 2 wt% S, along with no more than 4 wt% Si, less than 6 wt% O and up to 0.25 wt% H e.g., ref. 84. We stress, however, that the limit of 2 wt% S in the Earth’s core is driven by geochemical arguments and volatility trends e.g., refs. 85 and 86, while on the sole basis of thermo-elastic properties, Earth’s outer core could contain up to 10 wt%S (87, 88), or as much as 14.4 wt%S if it is assumed to be the only light element present (84).
Also here a total of ~ 20 wt% total light elements is a possibility.

The difference is that Mars core is expected to have more lighter elements and their data, while leaving out the question of a possible solid inner core, is more unambiguous in resulting in a high fraction of light element.
 
  • Like
Reactions: billslugg