There are a lot of meteor showers in December. At the beginning of the month, there are a lot of pheddens in the sky, and at the end of the month, there is a show by the Ursids. Jean Clark is credited with the image.
The Observer's Handbook of the Royal Astronomical Society of Canada states that there are 11 meteor showers that are considered to be the "principal" displays of the year. A particular shower must produce at least 10 meteors per hour in order to make the list.
The shower at the bottom of the list reaches its peak within eight days, while the shower at the top of the list reaches its peak within a week.
The most reliable and prolific of all the annual meteor displays is the Geminids.
There are stunning pictures of the Geminid meteor shower of 2021.
Kochab is the brighter of the two stars in the Little Dipper's bowl.
Kochab is positioned so close to the north pole of the sky that it never sets in for most viewers in the Northern Hemisphere. If you care to look, you can see these faint, medium-speed meteors all through the night.
The waning gibbous moon will cause the Ursids to be completely snuffed out this year. With the peak of the Ursids coming just a few nights after the full moon, these meteors will be in direct competition with what will be in essence a giant illuminated sky on the first full night of winter.
Even when viewing conditions are more favorable, hardly anyone ever attempts to observe these meteors.
The shower will peak on December 22. They will appear to be from the constellation Little Dipper. The image is from NASA/JPL-Caltech.
Observers have neglected the Ursids. Compared to the Geminids, which can produce up to 120 meteors per hour, the usual Ursid rate is a fraction of that; generally speaking, they produce about 10 or so per hour at their peak.
The earth has interacted with a dense stream of particles shed by this comet, which has caused brief outbursts of Ursid meteors numbering in the dozens per hour, such as in 1945 and 1986 If there was an unexpected spurt of activity, nobody would be around to see it. Their proximity to the Christmas holidays as well as the frigidity of late December nights are the most likely reasons.
The viewing conditions for the Ursids in 2021 will be intolerable.
Dodger fans used to say: better luck next year.
Joe is an instructor and lecturer at New York's Hayden Planetarium. He writes about astronomy in publications. Follow us on social media.
