All-sky cameras in Antarctica

Automatic Geophysical Observatories (AGO) operate at different places in Antarctica. The Automatic Geophysical Observatories of the American Polar Experiment Network for Geophysical Upper-Atmosphere Investigations PENGUIN are equipped with two-channel all-sky intensified CCD cameras operating at the two wave lengths of 427.8 nm and 630.0 nm simultaneously, and recording a long and a short exposure image each 2 minutes. The images have 10 km geographic resolution over most of the field of view, ranging to 30 km at the edges. Imager sensitivity is 20 Rayleigh in an 8-s exposure.

Monochromatic all-sky imagers are a powerful tool for observing and monitoring the optical aurora. The PENGUIn all-sky imagers are being used to

• Determine the polar cap auroral morphology under varied conditions of IMF, solar wind pressure and internal magnetospheric conditions
• Compare auroral dynamics to ionospheric plasma convection and magnetic variations
• Compare the optical aurora observed from the ground with satellite based observations.

This raw image was taken on May 7, 1995 at the AGO station P3. The left part shows the image in 427.8 nm wave length, the right part at 630.0 nm and the top points to the geomagnetic pole in Antarctica.

A very convenient way to produce first browse products of the data is the production of keograms, time sequences of stripes extracted from the all-sky images in the polar-equatorial or east-west directions.

Individual all-sky images can be produced for analysis, but in addition may be combined from contiguous AGO sites (and South Pole) and put onto a geographical or geomagnetic map.

Last update: 04 September 1997