2012 Perseid Shower

The annual Perseid meteor shower occurs when debris from Comet Swift-Tuttle intercepts the Earth at a high velocity (59 km/s, 133,000 mph). This debris is somewhat diffuse, so we see activity for many days on either side of the peak. Like most meteor showers, this is named for the constellation its members appear to originate in: Perseus.

Shower Summary

2012 Perseid CompositeThis is a composite image of 394 meteors collected between sunset on August 1 and sunrise on August 14 (thirteen evenings). Mouse over the image to see just the 123 Perseids recorded on the peak night of August 11/12. Since the images were collected over many hours, the radiant of the shower is not in a fixed location. However, because most of the meteors occurred between 2am and dawn, and because the radiant's high declination means it doesn't move fast, most of the meteors appear to point back to the same general area of the sky - just above the left center of the image. Note also that meteors farther from the radiant tend to make longer trails, since they have a smaller component of their velocity towards the camera.

All 394 of the meteors in this composite are Perseids. Several showers are currently active (Alpha Capricornids, Southern Delta Aquarids, Kappa Cygnids), but meteors from those are not shown.

The southwest monsoon pattern generally affects weather in Colorado during August. Storm systems have been too weak to drop much moisture (which the region desperately needs), but some cloudiness has generally been present in the evenings, reducing the number of meteors detected. The Moon only interfered a little with the early Perseids this year, and was not a factor from the peak and after. The Moon has been removed from the multiple night composite above, but is left in the image showing just events on the peak night.

Long string-like images are stars or planets captured as they traveled across the sky over many hours. Jupiter and Venus are near the Moon, and bright star trails are evident for Capella, Aldebaran, Deneb, Vega, and Altair.

Selected Fireball Videos

Perseid Frequency

2012 Perseid Distribution, Daily

This graph plots the distribution of meteors during the peak and the surrounding days. The raw count is distributed in 4-hour bins. One evening was clouded out. Because of the variable clouds encountered on most evenings this year, this chart should be interpreted more qualitatively than quantitatively.


© Copyright 2012, Chris L Peterson. All rights reserved.