Intensified charge-coupled-device imager for auroral studies

A 100 x 100 pixel charge-coupled-device area detector combined with an image intensifier, all-sky optics, and a filter wheel has been developed to provide quantitative monochromatic images of the aurora. The design provides for a variable exposure rate to accommodate the large dynamic range of auroral intensities, from a minimum of 20 ms up to several minutes. Standard auroral emission features are monitored by four selectable filters, normally at 6300, 5577, 3914, and 4278 A. Depending on the filter utilized, sensitivity can be from 180 to 250 R/ADU per s. The instrument has been used successfully in support of balloon, rocket, and satellite campaigns.