(2025-12-21 20:11:00) — Astronomical winter officially began today, as the Sun reached its southernmost point in the Northern Hemisphere sky.
The winter solstice, occurring at 10:03 A.M. EST, marks the start of astronomical winter in the Northern Hemisphere and astronomical summer in the Southern Hemisphere.
- The winter solstice occurred on December 20 at 10:03 A.M. EST, initiating astronomical winter in the Northern Hemisphere.
- A transit of Io and its shadow across Jupiter was observable on December 20.
- The Ursids meteor shower is predicted to peak on December 22, with approximately 10 meteors per hour under optimal conditions.
- The Ursids’ radiant is located near the Little Dipper’s cup, visible throughout the night for much of the Northern Hemisphere.
The winter solstice, which took place at 10:03 A.M. EST today, signifies the shortest day and longest night of the year in the Northern Hemisphere. After this date, the days will gradually grow longer as the Sun climbs higher in the sky.
The solstice marks the moment the Northern Hemisphere is tilted farthest from the Sun. Simultaneously, the Sun reached its highest point directly overhead at noon for those located on the Tropic of Capricorn in the Southern Hemisphere, initiating astronomical summer there.
Astronomical winter will continue until the spring equinox, which is expected to occur on March 20, 2026, at 10:46 A.M. EDT.
Sunrise: 7:19 A.M.
Sunset: 4:38 P.M.
Moonrise: 8:54 A.M.
Moonset: 5:59 P.M.
Moon Phase: Waxing crescent (4%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 10 P.M. local time from the same location.
Skywatchers can also look forward to the Ursids meteor shower, which peaks tomorrow morning, December 22. This short-lived shower is expected to produce around 10 meteors per hour under dark, clear skies.
The radiant point for the Ursids is located near the cup of the Little Dipper. Observers in the Northern Hemisphere will find the radiant nearly 50° high in the north by 5 A.M. local time, to the upper right of Polaris, the North Star.
What This Means for You
The winter solstice isn’t just an astronomical event; it’s a cultural touchstone celebrated for millennia. While the shortest day can feel challenging for those in the Northern Hemisphere, it also marks a turning point. From now until the spring equinox, daylight hours will gradually increase, offering a welcome return of sunlight. For those hoping to catch the Ursids meteor shower, a dark location away from city lights will maximize viewing opportunities. The shower’s radiant, near the Little Dipper, provides a helpful guide for locating these fleeting streaks of light.
Looking for more detailed information? Check out the full Sky This Week column from Astronomy magazine.
