Baltimore, Maryland – A groundbreaking study sheds light on the role of magnesium oxide, a crucial mineral in planet formation, in the early stages of super-Earth exoplanets’ development. Researchers have conducted high-energy laser experiments that reveal magnesium oxide as potentially the first mineral to solidify in the formation of these rocky planets, significantly impacting their geophysical evolution.
The study provides unprecedented insights into how atoms in magnesium oxide behave under extreme conditions, mimicking the heat and pressure found deep within a rocky planet’s mantle. This key mineral within Earth’s mantle plays a vital role in planetary formation, with the experiments suggesting it could be the primary mineral to solidify out of magma oceans during the formation of super-Earth exoplanets.
June Wicks, an assistant professor of Earth and Planetary Sciences at Johns Hopkins University, led the research and emphasized the importance of magnesium oxide in controlling the thermodynamics of young super-Earths. Understanding the behavior of this mineral could contribute significantly to determining whether a young planet will develop as a snowball or a molten rock, with implications on its geological features like water oceans, atmospheres, and more.
The findings, now published in Science Advances, highlight how the transition of magnesium oxide from one phase to another can impact the formation and evolution of terrestrial super-Earths. With rocky super-Earths expected to contain significant amounts of magnesium oxide, the mineral’s properties can influence crucial geophysical aspects such as the planet’s magnetic field and volcanic activity, much like on Earth.
To simulate the extreme conditions during planet formation, the research team subjected small samples of magnesium oxide to ultra-high pressures using high-power lasers. By tracking how the atoms rearranged under increasing pressures, the scientists observed the transformation of magnesium oxide from a solid to a liquid state, providing essential insights into its behavior in planetary interiors.
The study demonstrates the stability and simplicity of magnesium oxide under extreme pressures, offering valuable information for developing accurate theoretical models to study the behavior of this and other minerals within rocky planets like Earth. With magnesium oxide exhibiting a higher melting temperature than any other material, understanding its properties can provide crucial insights into the geological processes that shape young planets.
By showcasing the significant role of magnesium oxide in planetary formation, the research contributes to a better understanding of the complex interplay between minerals and geophysical processes in the evolution of super-Earth exoplanets. The study serves as a testament to the unique properties of magnesium oxide and its enduring impact on the geology of rocky worlds.