Science

by David Bjerklie

by Alice Park

by Erin Sharoni

by Jack Linshi

by Helen Regan

by NBC News

by Jack Linshi

by Tanya Basu

by TIME Video

by Salima Koroma and Ainissa Ramirez

by Katy Osborn

by Justin Worland

by TIME Photo

by Justin Worland

by Jeffrey Kluger