Astronomers discover a Neptune-mass alien world with Earth-like density

(Phys.org)—An international team of astronomers reports the discovery of a Neptune-mass exoplanet with a density comparable to Earth's. According to the research, the newly detected alien world, designated EPIC212521166b, is the most massive planet with a sub-Neptune radius found to date. A paper detailing the finding was published online on May 13 in a pre-print version on arXiv.org.