Distributed Optical Imaging of the Upper Atmosphere

This proposal describes an automatic sky imager capable of remotely and automatically imaging sub-visual optical emissions from the atmosphere. The USAF is charged with monitoring space weather, as well as modeling and forecasting space weather phenomena including equatorial plumes, auroral arcs, or polar cap patches. Surface observations are one of the few means available to determine upper atmospheric conditions over large regions. While space weather forecasts exist, they are frequently inaccurate and real time observations remain critical to assessing the earth-space environment. Ground-based environmental imaging systems are affordable, flexible, and accessible compared to space-based instruments, but are currently limited in operational utility primarily by tropospheric weather conditions and light sensitivity. If the field of view of a ground-based upper atmospheric imager is greater than the decorrelation distance for terrestrial cloud cover, a network of multiple imagers distributed many km apart, but with overlapping fields of view, could provide high-quality real-time space environment information. When favorable conditions allow for multiple overlapping observations, such a network could also provide products including tomographic reconstructions, ionospheric drift measurements, unambiguous emission heights, neutral density determinations, detection of clouds, and wind speed at the cloud base, a feat that currently requires costly radiosonde launches.