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Earth’s long-term, stable magnetic field is critical for being a habitable planet. Mars had a global magnetic field at ~4.3 billion years ago, which, however, only lasted for ~0.7 billion years. To decipher the origin of such short-lived dynamo, an international research team led by Dr. Wen-Pin Hsieh at the Institute of Earth Sciences, Academia Sinica, has precisely measured the thermal conductivity of iron-sulfur alloys at Martian core’s high pressure-temperature conditions. Research team demonstrated that Martian core is much more thermally conductive than previously inferred. Combined with numerical modeling on Martian core’s thermal evolution, they further found that such high thermal conduction with efficient cooling diminishes thermal convection, significantly contributing to the cessation of Martian dynamo. As the seismic data from Insight mission showed important advances in the internal structure of Mars, the research findings further provide crucial insights to the thermal and magnetic evolution, energy budget, and dynamics of Mars. The international team includes Drs. Wen-Pin Hsieh and Frédéric Deschamps of IES, etc. The results have been published in Science Advances on March 20, 2024.