2011 Orionid Shower

2011 Orionids Composite The annual Orionid meteor shower occurs when debris from Comet Halley intercepts the Earth at a high velocity (66 km/s, or 150,000 mph). This debris stream is somewhat diffuse, so we see activity for several days on either side of the peak.

This is a composite image of 292 Orionid meteors collected between sunset on October 17 and sunrise on October 25. The predicted peak was for the morning of October 22, which curiously showed a lower level of activity than the adjacent days. There was some minor interference from the Moon in earlier days of the shower (the Moon has been digitally removed from the composite). The skies were perfectly clear each night, so I believe that the odd pattern of activity is real, and not caused by the weather or lunar interference. Orionid activity was initially lower this year than it has been in previous years, but continued to rise well after the normal maximum.

Since the images were collected over many hours, the radiant of the shower is not in a fixed location. Long string-like images are stars or planets captured as they traveled across the sky over many hours.

During this time of year there are many minor showers active in addition to the Orionids, but those meteors are not shown in this image. Over the time frame of the composite, the camera captured Epsilon Geminids, Leo Minorids, Southern Taurids, Northern Taurids, and numerous sporadics.

Fireball videos:

This chart plots the total meteor activity over the days around the peak. The rate reflects only meteors brighter than about magnitude 1; a visual observer would have seen several times these rates.

2010 Orionid Activity

© Copyright 2011, Chris L Peterson. All rights reserved.