The Calcium-Aluminum Rich Crust of Super-Earth Exoplanet HD 219134 b
The Discovery of a High-Density Refractory World Located a mere 21 light-years from Earth in the northern constellation of Cassiopeia, HD 219134 b represents a cornerstone in the study of exoplanetary geology. Discovered using the radial velocity method via the High Accuracy Radial velocity Planet Searcher in the Northern hemisphere (HARPS-N) and later confirmed through transit observations by the Spitzer Space Telescope, this celestial body has redefined the classification of rocky worlds. As a "Super-Earth," a planet with a mass significantly higher than Earth’s but lower than that of gas giants like Neptune, HD 219134 b offers a rare look at the diversity of planetary compositions within our galactic neighborhood. While many Super-Earths are thought to possess deep hydrogen-helium envelopes or massive volatile-rich mantles, HD 219134 b belongs to a distinct and rarer sub-category: the refractory-rich terrestr...