60 SECONDS

摘要

Pears grow inside some heavy atoms, according to the most detailed peek yet at the nuclei in radium isotopes. In most elements, stable atoms have roughly spherical nuclei. But heavy, unstable atoms like radium can have arrangements of protons and neutrons with weird shapes. Studying the short-lived atoms could point to physics beyond the standard model. It's not all about melting ice. The Arctic Ocean is also acidifying faster than other oceans, according to a new report by the international Arctic Monitoring and Assessment Programme. It warns that acidification threatens food webs and the indigenous people who depend on them.