Outburst
A sudden, short-lived rise in a meteor shower's activity well above its normal level.
A meteor shower usually rises and falls gently around its peak, giving similar rates each year. Sometimes, however, rates suddenly jump for an hour or so. This is an outburst. It happens when Earth passes through a compact dust trail released by the parent comet during one particular return, perhaps decades or centuries ago, that planetary gravity has steered into our path. If the rate climbs above about 1,000 per hour, the outburst is called a meteor storm.
Outbursts are important because they test our understanding of how dust spreads out from comets. Since the late 1990s, computer models that follow individual dust trails have become good enough to predict many outbursts to within minutes, a big improvement on earlier guesswork.
The October Draconids are a well-known example: normally quiet, they produced a predicted outburst on 8 October 2011 that was observed by both visual watchers and radar. The Perseids also showed enhanced activity in 2016. The Alpha Monocerotids in November give short, rare bursts. Outburst meteors are dust-sized, so they never drop meteorites. Watching one needs no equipment; the key is checking predicted times and being out under a dark sky.
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