| December 2 | The Seven Sisters/Pliades |
| December 13 and 14 | Geminids Meteor Shower Predicted Peak |
| December 15 | Full Cold Moon |
| December 21 | Winter Solstice |
| December 22 and 23 | Ursids Meteor Shower Predicted Peak |
| December 25 | Christmas Crescent Moon and Spicia |
It’s been quite a year for space phenomena between April’s solar eclipse, brilliant auroras shining in unusual places during a strong solar storm, and a few interesting comets. We’re closing out the year with two annual meteor showers and exciting opportunities to catch our galaxy’s stars and planets. December’s nights in the Northern Hemisphere are also among the longest of the whole year, which just means more chances to bundle up and gaze up at the sky. Here’s what to look out for during the final month of 2024.
December 2– The Seven Sisters/Pliades
Beginning on December 2, a small, concentrated group of stars called the Pleiades, aka the Seven Sisters or Messier 45, will be visible in the eastern sky at 7:30 p.m. local time. According to the Farmer’s Almanac, the Seven Sisters star cluster may be one of the first astronomical subjects ever recorded. It was known to the Greek poet Hesiod almost 3,000 years ago and it is referenced in Chinese records dating back to 2357 BCE. It is also mentioned three times in the Bible.
It is about 410 light years away from Earth and about 20 light-years across. It formed about 20 million years ago–making it relatively young in star terms–and contains several hundred stars.
The Pleiades lie within the constellation of Taurus, which you can find by identifying the famous constellation of Orion the Hunter and its distinct ‘belt’ of three stars. According to The Royal Greenwich Museum, you can then follow the line formed by the belt upwards until you see a bright reddish star called Aldebaran, which is the eye of the bull in Taurus. From Aldebaran, continue in the same direction until you see a compact group of blue stars.
[Related: ‘Christmas tree’ galaxy shines in new image from Hubble and JWST.]
December 13 and 14– Geminids Meteor Shower Predicted Peak
The annual Geminid meteor shower is generally one of the most reliable meteor showers of the year. The Geminids are predicted to peak on December 13 and 14. However, this year it butts up against the full moon, so it will be a bit more difficult to see shooting stars due to the moonlight. Looking at 2 a.m. local time in a dark place on December 13 should offer the best chances to catch this shower.
Many of the Geminid meteors are particularly bright and white, so they may stick out against the moonlight.
December 15– Full Cold Moon
The last full moon of the year will reach peak illumination on December 15 at 4:02 a.m. (EST). To calculate when the Cold Moon will rise near you, you can consult the Old Farmer’s Almanac moonrise calculator.
The Cold Moon is a Mohawk named that references the cold air that grips the Northern Hemisphere this time of year. Other names for December’s full moon include the Big Winter Moon or Gichi-bibooni-giizis in Anishinaabemowin (Ojibwe), the Dead of Winter Moon or Ukiugraq in Inupiat and the Winter Moon or Joto:h in Seneca.
December 21– Winter Solstice
The first day of winter in the Northern Hemisphere is marked by the winter solstice. The solstice officially arrives on Saturday, December 21 at 4:21 a.m. EST.
Because the Earth is tilted on its axis, one half of the planet is pointed away from the sun and the other half is pointed towards it during the winter and summer solstices. Technically, the solstice only lasts a moment, when a hemisphere–in this case, the Northern–is tilted as far away from the sun as it can be.
[ Related: What is a solstice? And other questions about the shortest day of the year, answered. ]
The winter solstice is also the shortest day of the year. Those of us in the Northern Hemisphere will see the fewest hours of sunlight on the 21st. Afterwards, the days will continue to grow longer until the summer solstice in June.
December 22 and 23– Ursids Meteor Shower
In case the Cold Moon really blocks out the Geminids, you won’t have to wait too long for another meteor shower. The 2024 Ursid meteor shower is predicted to peak on December 22 and 23. According to EarthSky, the Ursids are a little bit more low key than Geminids, but still worth investigating
Under a clear sky, there can be about five to 10 meteors per hour. To catch this final meteor shower of 2024, look towards the Little Dipper in the constellation Ursa Minor during the early morning hours.
December 25– Christmas Crescent Moon and Spica
If you are up before sunrise Christmas morning, you can spot a crescent moon next to the star Spica. This is the brightest moon in the constellation Virgo. You can consult the Farmer’s Almanac crescent moon calendar to calculate the best time to look near you.
The same skygazing rules are key this month: Go to a dark spot away from the lights of a city or town and let your eyes adjust to the darkness for about 30 minutes.
