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Related Experiment Video

Updated: Sep 9, 2025

Simulation of the Planetary Interior Differentiation Processes in the Laboratory

Simulation of the Planetary Interior Differentiation Processes in the Laboratory

Published on: November 15, 2013

Seismic detection of a 600-km solid inner core in Mars.

Huixing Bi^1,2, Daoyuan Sun^3,4, Ningyu Sun^2,5

¹National Key Laboratory of Deep Space Exploration/School of Earth and Space Sciences, University of Science and Technology of China, Hefei, China.

|September 3, 2025

Summary

Mars possesses a solid inner core, confirmed by InSight seismic data. This discovery impacts our understanding of the planet

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Area of Science:

Planetary Science
Seismology
Geophysics

Background:

Rocky planet cores influence composition, thermal evolution, and magnetic history.
Martian core is known to be at least partially liquid, but solid state is unconfirmed.

Purpose of the Study:

To determine if Mars has a solid inner core using seismic data.
To characterize the properties and implications of a Martian inner core.

Main Methods:

Analysis of seismic data from the InSight mission.
Identification of seismic phases (PKKP, PKiKP) indicative of an inner core.
Inversion modeling to constrain inner core radius and properties.

Main Results:

Demonstrated the presence of a solid inner core on Mars.
Constrained the Martian inner core radius to 613 ± 67 km.
Observed a ~30% compressional velocity jump at the inner core boundary.

Conclusions:

Martian inner core likely contains segregated light elements from core crystallization.
Provides a key data point for understanding Mars's thermal and chemical state.
Informs models of Martian magnetic field evolution and planetary dynamo generation.