New rock types from exoplanets containing unusual ratios of minerals have been discovered around white dwarf stars, according to a new study.
New rock types containing unusual ratios of minerals have been discovered around white dwarf stars, according to a new study. Published in the journal Nature Astronomy earlier this month, the study suggests that these rocks are remnants of the exoplanets which got ripped apart while orbiting their star as it transitioned into a dying white dwarf star. This happens as the dying star’s strong gravitational force pulls them towards it. To confirm the existence of these alien rocks, astronomers reportedly studied 23 white dwarfs located within 650 light-years of the sun and determined the ratio of earth-like elements present in the destroyed worlds by analysing the light emitted by those stars.
Surprisingly, the geological makeup of our planet matched to the exoplanet remnants around only one white dwarf star whereas the rocks around other white dwarfs exist nowhere on Earth and even in the entire solar system. Siyi Xu, lead author of the study and an astronomer at the National Optical-Infrared Astronomy Research Laboratory (NOIRLab) said as per Live Science–
“While some exoplanets that once orbited white dwarfs appear similar to Earth, most have rock types that are exotic to our solar system. They have no direct counterparts in the solar system.”
Experts found surprising results while classifying the alien rocks
To classify the rocks scattered around the white dwarf stars, study experts used a specific set of calculations that are also used to classify rocks found here on Earth. According to researcher Keith Putirka, the results of the calculations were surprising as the rocks were composed of minerals that were unexpected to be found. In an interview with Live Science, he was reported saying, “On Earth, rocks that occur in the mantle consist of mostly three minerals, olivine, orthopyroxene, and clinopyroxene. But the ratio of elements in most polluted white dwarfs showed that some of these minerals would have been unlikely to form’.
It was found that the rocks contain different formulations of magnesium-rich minerals, something which is not expected to be present inside the solar system. Reportedly, the experts have created new names like “quartz pyroxenites” and “periclase dunites” to classify the minerals although it is still unclear how many types of such minerals exist. According to Putirka, an understanding of this alien composition requires further experiments and observations.