WATCH: A test run of New York City’s ball drop concluded successfully in Times Square on December 30, less than 48 hours before the final countdown to New Year’s Eve. The Constellation Ball is the largest New Year’s Eve Ball ever, containing 5,280 crystals and LED light pucks. It will remain dark until the final countdown, seconds before midnight on December 31, 2025. COURTESY: Reuters | GMA News

Pluto has a thin atmosphere with a blue tint. Find out what else makes the "King of the Kuiper Belt" interesting. Stream "The Planets: Ice Worlds" online or on the @PBS app now: https://to.pbs.org/2YztewN | NOVA l PBS

Ever wondered what makes Pluto so unique? From the unexpected story behind its name to just how cold it really is on its surface, these five facts about this distant planet will surprise you. | National Geographic