The Quadrantids (pronounced KWA-dran-tids) are a meteor shower that happens every January. It is an odd shower compared to others. It was discovered relatively recently, has a short peak period, and the constellation that gave them their name no longer exists.
For specifics on when and how to watch the shower's peak this year, check our Quadrantid Meteor Shower Guide.
According to Space.com skywatching columnist Joe Rao, the first report of the Quadrantids came from Adolphe Quetelet, who observed the meteor shower in 1825 while working at the Brussels Observatory. Other astronomers in the United States and Europe also noted the shower in the years following.
At the time, the radiant, where the meteors appear to stream away from, appeared in the constellation Quadrans Muralis, which was designated by French astronomer Jerome Lalande in 1795. The constellation was named after an astronomical instrument used to observe and plot stars, according to NASA. Quadrans Muralis is located between the constellations Draco and Boötes, near the handle of the Big Dipper.
In 1922, the International Astronomical Union formed a list of modern constellations and elected not to include Quadrans Muralis. Some astronomers suggest the meteor shower could now be called the Boötids, since the radiant falls in the constellation Boötes. However, there is already a meteor shower by that name, which occurs in late June in the Southern Hemisphere.
The Quadrantids have a somewhat odd origin. While most meteor showers come to be from comet fragments, the body responsible for producing the Quadrantids is asteroid 2003 EH1, which astronomers sometimes call a "rock comet."
As the name of the asteroid implies, it was found very recently — 2003 — by astronomer Peter Jenniskens, a meteor expert with the SETI Institute in California. He discovered that the orbit of this asteroid (the space rock is about 1.2 miles in diameter, or 2 kilometers) fit "snug in the shower," Rao wrote.
Adding another layer of intrigue, some astronomers believe 2003 EH1 is the remainder of comet C/1490 Y1, which was lost to history after a prominent meteor shower was mentioned in Chinese records in 1490. It is possible the sky display came from a breakup of part of the comet.
Viewing the shower
While most meteor showers peak over a few days, the Quadrantids have a narrow peak of only a few hours. Despite its short peak, however, the meteor shower is often marked by large "fireball" meteors that look more colorful, appear brighter and last longer than a typical meteor. At peak times, providing the moon and other lights don't wash them out, viewers will see about 120 meteors an hour, NASA said. [Related: Quadrantid Meteor Shower Wows Stargazers]
Quadrantids are a nice New Year's treat for the Northern Hemisphere, as they arrive in early January. Since the more northern parts of the hemisphere are likely under a deep freeze at that time, skywatchers are advised to bundle up as meteor shower watching tends to last a few hours.
NASA advises skywatchers to find a spot that is sheltered from city or street lights, and ideally to bring something like a sleeping bag or chair to keep you off the ground (or snow, as it may be the case.) The radiant of the shower is somewhat in between the handle of the Big Dipper and the head of the constellation Draco, but it is recommended to look away from it as the meteors further from the radiant will appear for longer.
The meteor shower, however, can be a challenge to see, Rao wrote in a past article. Several factors combine to produce this: the peak period tends to be only six hours, the radiant is only visible between about 2 a.m. and 7 a.m. local time, it's extremely cold in the Northern Hemisphere, and the moon interferes once in every three-year period.
This article was updated on Dec. 10, 2018 by Space.com Associate Editor Sarah Lewin.