After the Peak: How Long Does a Meteor Shower Last?
I had a question on Twitter asking whether it was worth while looking out for any Perseid meteors tonight after the shower peaked yesterday.
While individual meteors are short blink-and-you’ll-miss-them events, meteor showers themselves last many days, sometimes weeks. The rate of meteor activity builds up in the days before the peak, and tails off afterwards. The peak itself lasts a few hours, maybe a day or so for some broad-peaked showers.
Take a look at this graph of activity for the Perseids meteor shower 2013:
The number of meteors per hour under ideal conditions (known as the ZHR, the Zenith Hourly Rate) built up to around 20 meteors//hour during the month before the peak. The rate started to increase around 9 Aug, doubling to 40 meteors//hour around 11 Aug, before tripling again to 120 meteors//hour around 13 Aug at the peak. The drop off was quicker, but even for the two days after the peak the rate was still above 20 meteors//hour.
So even in the days after the peak of the Perseids rates of meteors stat well above the background rate, at least 4 or 5 times that for a couple of nights.