Mercury has an 11-mile thick diamond layer between its core and mantle
Mercury possesses an 11-mile thick diamond layer between its core and mantle, formed from carbon-rich magma crystallization.
Mercury, the smallest planet in the solar system, houses an 11-mile thick diamond layer between its core and mantle, as detailed by scientists from China and Belgium in Nature Communications. This layer was formed from the crystallization of Mercury's carbon-rich magma ocean during the planet's cooling phase, challenging prior assumptions about carbon's stable phases at that time.
Researchers used high-pressure and temperature experiments along with thermodynamic modeling to simulate Mercury's internal conditions, achieving pressures up to 7 Giga Pascals. Their study found that sulfur in Mercury's iron core facilitated the formation of the diamond layer, altering the liquidus temperature of the magma ocean and influencing planetary differentiation.
This diamond layer significantly impacts Mercury's thermal dynamics and magnetic field generation by transferring heat from the core to the mantle. The study's findings extend to exoplanetary systems and terrestrial planets with similar compositions, suggesting that similar diamond layers could exist elsewhere under the right conditions.