A Supernova Was Hiding in Antarctica’s Snow
https://www.nytimes.com/2019/08/19/science/antarctica-snow-supernova.html Source: By Katherine Kornei, The New York Times. Excerpt: Earth is continuously plowing through extraterrestrial dust. Tens of thousands of tons of the stuff, mostly from asteroids and comets, settles all over the planet every year. ...Recently, scientists analyzed dust collected from Antarctic snow and found an excess of radioactive iron. After ruling out contamination from nuclear weapons testing and other sources, the team concluded that the iron was produced by supernovas, fleeting explosions of stars more massive than the sun. This discovery suggests that stellar blasts might have rocked Earth and the rest of the solar system in the not-too-distant past. The results were published on Aug. 12 in Physical Review Letters [ https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.123.072701 ]. Meteorite hunters are drawn to Antarctica because the space rocks, which are dark, stand out against the snow...