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Images submitted by Richard Bassom

When Richard sent me this image of the Quadrantid meteors he had recorded on the night of 3/4 January I asked some quetions. His comprehensive reply was as follows.

"The camera is a Sony Starvis CMOS detector with a 4mm lens, so the field of view is about 90 degrees horizontally by 45 degrees vertically. The camera has a limiting magnitude of about +7 at video frame rates of 25 frames per seconds, so 40 milliseconds per exposure. The total duration was the entire night, but most of the night was cloudy, so some of these meteors were before midnight, but most were detected after around 4am. Only images of meteor detections are shown in the stacked image. The camera is fixed, so as you say, the radiant moves during the night.

The camera is controlled by a Raspberry Pi computer, which does all of the video acquisition and meteor detection. It records and calculates the time, alt/az and ra/dec position of the meteor and velocity throughout its flight. All of this data is uploaded to the Global Meteor Network at the end of each night for analysis and matching with observations from other meteor stations. It is possible to use some free software called UFOOrbit with the data, which reads the data and shows the meteor tracks and the position of the radiant (see attached image), from which you can see that the majority of the meteors that night were from the Quadrantid radiant."