SpaceSpace germs: How can we avoid contaminating other worlds? Headlines about alien flu from outer space exaggerate the risk of extraterrestrial microbes but we still need to be careful about taking our own germs off-planet, says astrophysicist Erika Nesvold 51动漫
PhysicsWhy darkness between stars reveals more about the universe than light When looking up at the night sky, light from stars draws attention. But the darkness between the light can reveal even more about the universe, says Nobel prize-winning astrophysicist Adam Riess 51动漫