Jesús Martínez Frías
Planetary geologist and astrobiologist at the IGEO (CSIC-UCM). Academician of the Royal Academies of Sciences and Doctors of Spain. President of the Planetary Geology Commission of the Geological Society of Spain and of the Spanish Network of Planetology and Astrobiology.
This is a very interesting and high-quality study that underscores the importance of geophysics and in situ analysis on Mars, beyond existing theoretical models of the Red Planet's core.
The study fits with existing evidence. Previous observations on Mars had confirmed that the core was partially liquid, but thanks to the InSight mission, we know that the inner core, specifically, is solid.
I find it very interesting that the solidity pattern of the inner core follows the same patterns as on the Moon and Earth, suggesting analogies in the evolution of their differentiation processes after accretion.
The geophysical implications relate to the geodynamics of Mars itself, its loss of its magnetic field, models of planetology compared to other planetary bodies, such as Mercury or Ganymede, and also to the existence, even today, of a possible "Martian geological vitality" in terms of the interaction between the outer and inner core, which could even be important for astrobiological purposes.
The research is very well developed, but obviously more geophysical studies are needed, with more missions similar to InSight.
Furthermore, we only have a current "snapshot" of the interior of Mars, and it would be interesting to know, through paleomagnetism studies of rocks and minerals, how it has evolved over the billions of years since its origin and whether this may have also influenced possible heterogeneities in the mantle.