Quadrantids
Encyclopedia
The Quadrantids are an easily visible January meteor shower
Meteor shower
A meteor shower is a celestial event in which a number of meteors are observed to radiate from one point in the night sky. These meteors are caused by streams of cosmic debris called meteoroids entering Earth's atmosphere at extremely high speeds on parallel trajectories. Most meteors are smaller...

.

The radiant
Radiant (meteor shower)
The radiant or apparent radiant of a meteor shower is the point in the sky, from which meteors appear to originate. The Perseids, for example, are meteors which appear to come from a point within the constellation of Perseus....

 of this shower is an area inside the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....

 Boötes
Boötes
Boötes is a constellation in the northern sky, located between 0° and +60° declination, and 13 and 16 hours of right ascension on the celestial sphere. The name comes from the Greek Βοώτης, Boōtēs, meaning herdsman or plowman...

. The name comes from Quadrans Muralis
Quadrans Muralis
Quadrans Muralis was a constellation created by Jérôme Lalande in 1795. It was located between the constellations of Boötes and Draco, near the tail of Ursa Major...

, an obsolete constellation
Former constellations
Former constellations are constellations that are no longer recognized by the International Astronomical Union for various reasons. Many of these constellations existed for long periods of time, even centuries in many cases, which means they still have a large historical value and can be found on...

 that is now part of Boötes. It lies between the end of the handle of the Big Dipper and the quadrilateral of stars marking the head of the constellation Draco.

Adolphe Quetelet of the Brussels Observatory discovered the shower in the 1830s, and shortly afterward it was noted by several other astronomers in Europe and America.

The peak intensity is exceedingly sharp: the meteor rates exceed one-half of their highest value for only about 8 hours (compared to two days for the August Perseids). This means that the stream of particles that produces this shower is narrow – and apparently deriving from and within the last 500 years from some orbiting body. The parent body of the Quadrantids was recently tentatively identified (in a paper by Peter Jenniskens) as the minor planet 2003 EH1
2003 EH1
2003 EH1 is a celestial body.This astronomical body was discovered during March of 2003. P.Jenniskens proposed the asteroid as the parent of the Quadrantid meteor shower. - Sources : retrieved 15:18 13 October 2011...

, which in turn may be the same object as the comet C/1490 Y1 which was observed by Chinese, Japanese and Korean astronomers 500 years ago.

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