Meteors from an Obsolete Constellation

Old star map showing the constellation Quadrans
In this old German star map, the obsolete constellation Quadrans, after which the Quadrantid meteors are named, lies between Boötes, the Herdsman and Draco, the Dragon (Drache). This map is reproduced from the 1799 edition of Christoph F. Goldbach's Neuester Himmels-Atlas.
Early each January the Quadrantid meteor stream provides one of the most intense annual meteor displays with a brief, sharp maximum lasting only a few hours. Adolphe Quetelet of Brussels Observatory discovered the shower in the 1830's, and shortly afterward it was noted by several other astronomers in Europe and America.

The Quadrantids are named after the obscure constellation Quadrans Muralis, the Mural Quadrant, depicted in some 19th-century star atlases near where Draco, Boötes, and Hercules now meet. The figure was invented in 1795 by Joseph J. Lalande to commemorate the instrument used to observe the stars in his catalogue. It was removed in the 1920s when the International Astronomical Union adopted the modern list of 88 officially recognized constellations. Most of Quadrans Muralis ended up in Boötes, but the meteor shower kept its name, likely because there's already a minor shower eminating from Boötes during January — the Bootids.

The shower's origin is a small, recently discovered asteroid-like body, according to meteor expert Peter Jenniskens (NASA/Ames Research Center). The source is a chunk of rock just a couple of kilometers wide found in March 2003 and designated 2003 EH1. It has an odd, high-inclination orbit that matches the orbit of the Quadrantids when both are tracked back through several centuries of planetary perturbations. Jenniskens estimates that the Quadrantid meteoroids we encounter today left 2003 EH1 only about 500 years ago. The association of 2003 EH1 with the Quadrantid stream identifies it as a dead short-period comet, much like the "asteroid" 3200 Phaethon, source of the Geminid shower.

Quadrantid meteor
A 2003 Quadrantid meteor streaks through the sky just above the Southern Cross.
The 2006 Quadrantid meteor shower is due to peak on January 3rd, around 18h Universal Time. This corresponds to the predawn period in the Far East, around the time the shower’s radiant, halfway between the head of Draco and the end of the Big Dipper’s handle, is highest in the sky.

The “Quads” have a very sharp peak lasting only a few hours. But if you’re watching when it arrives, this can be one of the year’s best meteor displays. As many as 40 or more of these moderately swift meteors may be seen per hour between midnight and dawn. And since the waxing crescent Moon will have set in early evening, even faint meteors should be visible in a dark sky.

Use our interactive sky chart
to see the appearance of the heavens at 2:00 a.m. during the peak morning of the Quadrantids. The chart is set at 40° north latitude for central North America. Click on the "change" button to alter either the date and time or viewing location displayed by the chart.

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