The Draconid meteor shower has a history of outbursts. While the shower normally does not generate much activity, from 1 to 2 meteors an hour at peak for a shower that runs between October 6 and 10, past increases in activity have been documented. Technically, a meteor "storm" requires more than 1,000 meteors an hour, but this has occurred before for the Draconids, in 1933 and 1946. Lesser storms, more accurately referred to as outbursts, occurred in 1952, 1985, and 1998, with hundreds of meteors an hour.
The Draconid Meteor Shower of 2011
The Draconid Meteor Shower occurs each October between the 6th and 10th, with the peak of activity around the 8th. The meteor shower occurs when Earth passes through the trail of debris left behind by the comet Giacobini-Zinner.
Predictions made a year in advance of the date put the output at about 750 meteors an hour at peak, just shy of a storm. The shower favors locations in northern Africa, the Middle East and Europe. This is because this portion of the Earth will be plowing headfirst into the stream of debris at the proper time. But observers in other locations are encouraged to watch as well.
The meteors appear to emanate from the constellation Draco the Dragon. Draco is a north circumpolar constellation, meaning that it closely circles the north pole star and never sets for observers in the Northern Hemisphere. Although the meteors could appear at any location in the sky, if you trace them backward on their paths, they will seem to intersect at a "source" in Draco.
Past Meteor Storms
Another meteor shower that is quiet during regular years but occasionally produces a nice storm is the Leonids. The Leonid meteor shower generally peaks in the predawn hours of November 17. A Leonid storm occurred in 1999, and storms in 1966 and 1833 were especially notable in North America. Up to hundreds of thousands of meteors were reported an hour.
A term common in meteor showers is the Zenithal Hourly Rate (ZHR). A ZHR over 1000 is a storm, yet anything with a ZHR of around 10 is still considered a good meteor shower. Scientists estimate the frequency of meteor storms at about once a decade, but even then the storms usually favor just one section of the globe. Most people have never seen a meteor storm.
Regardless of where you live, make sure you mark your calendar for October 8, 2011. Even if you don't see a storm, you may see an outburst or a better-than-average display. Just hope for clear skies!
Source: 2011 Draconids: Storm or Just an Outburst? paper by Vaubaillon, Sato, and Watanabe
Kelly Whitt - I have been a professional writer for more than a decade, covering many topics from science-based articles to do-it-yourself home ...
