The Quadrantid meteor shower, named for the obsolete constellation Quadran Muralis, will appear to stream from a point in the sky called the radiant (yellow star), located below the end of the Big Dipper's handle and across from the bright, orange-red star Arcturus. The map shows the sky around 4 a.m. local time Tuesday, Jan. 3. The shower will be best between 4 a.m. and 6 a.m., the start of dawn. Map: Bob King, Source: Stellarium
If one of your New Year's resolutions is to spend more time under the stars in 2017, you'll have motivation to do so as soon as Tuesday. That morning, the Quadrantid (kwah-DRAN-tid) meteor shower will peak between 4 to about 6 a.m. local time just before the start of dawn. This annual shower can be a rich one with up to 120 meteors flying by an hour — under perfect conditions.
Those include no moon, a light-pollution free sky and most importantly, for the time of maximum meteor activity to coincide with the time the radiant is highest in the pre-dawn sky. Timing is everything with the "Quads" because the shower is so brief. Meteor showers occur when Earth passes through either a stream of dusty debris left by a comet or asteroid. With the Quads, asteroid 2003 EH1 provides the raw material — bits of crumbled rock flaked off the 2-mile-wide (~3-4 km) object during its 5.5 year orbit around the sun.
A Quadrantid fireball flares to the left of the Hyades star cluster and Jupiter in 2013. As Earth travels across the debris stream, bits and pieces of asteroid 2003 EH1 strike the atmosphere at nearly 100,000 mph (43 km/second) and vaporize while creating a glowing dash of light called a meteor. Credit: Jimmy Westlake via NASA
Only thing is, the debris path is narrow and Earth tears through it perpendicularly, so we're in and out in a hurry. Just a few hours, tops. This year's peak happens around 14 hours UT or 8 a.m. Central time (9 a.m. Eastern, 7 a.m. Mountain and 6 a.m. Pacific), not bad for the U.S. and Canada. The timing is rather good for West Coast skywatchers and ideal if you live in Alaska. Alaska gets an additional boost because the radiant, located in the northeastern sky, is considerably higher up and better placed than it is from the southern U.S. states.
Another Quadrantid fireball. Credit: NASA
The Quads will appear to radiate from a point in the sky below the Big Dipper's handle, which stands high in the northeastern sky at the time. This area was once home to the now defunct constellation Quadrans Muralis (mural quadrant), the origin of the shower's name. As with all meteor showers, you'll see meteors all over the sky, but all will appear to point back to the radiant. Meteors that point back to other directions don't belong to the Quads are called sporadic or random meteors.
The long-obsolete constellation Quadrans Muralis represents the wall quadrant, a instrument once used to measure star positions. It was created by French astronomer Jerome Lalande in 1795. Credit: Johann Bode atlas
Off-peak observers can expect at least a decent shower with up to 25 meteors an hour visible from a reasonably dark sky. Peak observers could see at least 60 per hour. Tropical latitude skywatchers will miss most of the the show because the radiant is located at or below the horizon, but they should be on the lookout for Earthgrazers, meteors that climb up from below the horizon and make long trails as they skirt through the upper atmosphere.
Set your clock for 4 or 5 a.m. Tuesday, put on a few layers of clothing, tuck hand warmers in your boots and gloves, face east and have at it! The Quads are known for their fireballs, brilliant meteors famous for taking one's breath away. Each time you see one chalk its way across the sky, you're witnessing the fiery end of an asteroid shard. As the crumble burns out, you might be fulfilling another resolution: burning away those calories while huddling outside to see the show.
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