Winter solstice marks turning point for early sunsets
If early sunsets and long, cold nights aren't exactly your cup of tea, December offers both a high point and a low point for you. Yes, the darkest day of the year is in December, but after the winter solstice passes, we start to experience more and more daylight each day in the months ahead.
The winter solstice occurs between Dec. 20 or 23 each year, but it's usually on Dec. 21 or 22. This year, the solstice will occur at 3:19 a.m. Dec. 21. That's the moment when the sun's path will be at its northernmost or southernmost point, depending on which hemisphere you are in, according to NASA. In the Northern Hemisphere, the December solstice is the shortest day and longest night of the year, while in the Southern Hemisphere, it is the longest day and shortest night. The opposite is true of the June solstice. For those of us in the Northern Hemisphere, that's the summer solstice, and it's the longest day and shortest night of the year. But in the Southern Hemisphere, where the June solstice marks the start of winter, it's the shortest day and longest night.
The long, dark nights of December provide some peak skywatching opportunities. For starters, two meteor showers are active and hit their peak in December. The first, the Geminids, runs from Dec. 2 to 21, peaking the night of Dec. 12 to 13. The Geminids is typically the strongest meteor shower of the year, and peak viewing time is before midnight instead of in the predawn hours, as is the case with many meteor showers. However, this year, the moon will put a damper on the peak viewing opportunities, the American Meteor Society reports. On the night of its peak, the moon will be 92% full, creating bright night skies that will dim our chances of seeing a meteor streaking across the sky.
A little later in December, the Ursids gets underway. This meteor show, which runs from Dec. 16 to 26, isn't as much of a show stopper as the Geminids, but it can sometimes produce in excess of 25 meteors per hour, the meteor society reports. It will peak the night of Dec. 21 to 22, when the moon will be 59% full.
A third meteor shower, the Quadrantids, also gets its start in December, running from Dec. 16 to Jan. 16. However, it doesn't peak until just after the new year, on the night of Jan. 2 to 3. The peak coincides with a new moon, so a dark night sky will amplify the viewing opportunities for this shower, according to the meteor society.
In between all the meteor activity are a few opportunities to glimpse the planets in the night sky. On Dec. 4, Venus will be visible just above the crescent moon soon after the sun sets. Venus and the moon are the brightest two objects in the night sky, National Geographic reports.
Just a few days later, Jupiter will be at opposition on Dec. 7. When it is at opposition, it is at its closest point to Earth and also fully illuminated by the sun, which means it will be brighter in the sky than at any other time of year. The only things that will shine brighter than Jupiter on the night of Dec. 7 will be the moon and Venus, EarthSky reports. At midnight, look for it high in the night sky, about where the sun is at high noon.
To round out the month, Mercury will be at its greatest western elongation on Dec. 25. This is the point at which Mercury is the farthest from the rising sun, according to EarthSky. Mercury is the closest planet to the sun, orbiting it every 88 days. This means it goes back and forth between its greatest eastern and western elongations throughout the year.
In the days surrounding its greatest western elongation, Mercury is visible in the sky just before the sun rises, EarthSky reports. To find it, look to the east, where the sun is rising. It will be just above the horizon. By the time we ring in 2025, it will disappear from view.
December's full moon will be visible in the night sky on Dec. 15. It will reach its fullest point at 3:02 a.m. that day, so it will appear full on both Dec. 14 and 15.
The most commonly used name for the December full moon is the cold moon. The nickname was coined by Native Mohawks because of the cold conditions that are typical of December, according to the Old Farmer's Almanac. Other seasonally appropriate nicknames used by Native tribes for the December full moon include the long night moon, the snow moon and the winter maker moon. Ancient pagans in Europe called December's full moon the moon before yule.
Want to stargaze with us this winter? Sign up for a program in our Constellation Walk of Fame series. These four programs, held from January to March, will showcase constellations in the night sky on evening hikes through Hickory Creek Preserve, Goodenow Grove Nature Preserve, Prairie Bluff Preserve and Kankakee Sands Preserve.