Why Do We Have a Leap Year Anyway?
Without adding an extra day to February every four years, our calendar would get increasingly out of sync with the cosmos

© Olivier Le Moal/Getty Images
Without adding an extra day to February every four years, our calendar would get increasingly out of sync with the cosmos

© Olivier Le Moal/Getty Images
Despite being some six billion kilometers away, the sun from Pluto would be a dazzling sight to behold—carefully, that is

© NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute