Some stars in our galaxy could harbour planets with thick layers of diamond in their mantles. They may sound like prime real estate but new lab experiments suggest that these blingworlds, though carbon-rich, would be cold, devoid of most of the mechanisms that sustain life on Earth. Our solar system is relatively carbon-poor. Consequently, Earth's core is made of iron and its mantle of silica-based minerals. Some stars have high carbon-to-oxygen ratios compared with the sun, however, and such stars might host planets with mineral compositions very different from that of Earth. Read more
A planet made of diamonds may sound lovely, but you wouldn't want to live there. A new study suggests that some stars in the Milky Way could harbour "carbon super-Earths" - giant terrestrial planets that contain up to 50 percent diamond. But if they exist, those planets are likely devoid of life as we know it. The finding comes from a laboratory experiment at Ohio State University, where researchers recreated the temperatures and pressures of Earth's lower mantle to study how diamonds form there. Read more