Automated detection of the magnetopause for space weather from the IMAGE satellite

The Radio Plasma Imager (RPI) is a low power radar on board the IMAGE spacecraft to be launched early in year 2000. The principal science objective of RPI is to characterize the plasma in the Earth's magnetosphere by radio frequency imaging. A key product of RPI is the plasmagram, a map of radio signal strength vs, echo delay-time vs. frequency, on which magnetospheric structures appear as curves of varying intensity. Noise and other emissions will also appear on RPI plasmagrams and when strong enough will obscure the radar echoes. RPI echoes from the Earth's magnetopause will be of particular importance since the magnetopause is the first region that the solar wind impacts before producing geomagnetic storms. To aid in the analysis of RPI plasmagrams and find all echoes from the Earth's magnetopause, a computer program has been developed to automatically detect and enhance the radar echoes. The technique presented is derived within a Bayesian framework and centers on the construction and analysis of a Likelihood Function connecting magnetospheric structures and RPI plasmagrams. Once this technique has been perfected on archival IMAGE data it will be recoded and used on board the IMAGE spacecraft in a series of tests thereby greatly facilitating organizations like the National Oceanic and Atmospheric Administration's (NOAA) Space Environment Center (SEC) to perform real-time analysis of space weather.