The winter solstice is here today (Dec. 21), marking the shortest day and longest night of the year for the Northern Hemisphere.
As the astronomical start of winter, today is the moment the sun reaches its lowest point in the sky as seen from Earth. At noon, it appears directly over the Tropic of Capricorn, a latitude of 23.5 degrees south, creating the least daylight of the year for the Northern Hemisphere, which is tilted as far from the sun as it gets.
