Over forty years of intermittent observations have established that the aurora emits radio noise which can be observed on the ground. Surprisingly, despite the intensity with which the aurora is studied, very little is known about these radio emissions, their frequency-time characteristics, their occurrence statistics, or their generation mechanisms. This grant will support an investigation into the spectrum of radio emissions from the aurora in the frequency range 0.2-20 MHz using an inexpensive ground-based "smart" system, consisting of a radio receiver and data storage device controlled by a small computer. This will be located near Fairbanks, Alaska at the site of previous measurements of auroral radio emissions, thus saving time and expense of finding a low-noise location. Other instruments are located nearby to support the measurements, and the Geophysical Institute in Fairbanks will provide on-site assistance. The scientific motivation for this grant may be summarized as follows: 1) To better characterize the earth's radio environment; 2) To study space plasma physics processes from the ground by observing the radio signatures of those processes; and 3) To explore possibilities of using radio emissions as an index of auroral activity. Although radio emissions comprise a small fraction of the total energy of the aurora, they may provide important clues to the more energetic processes, in analogy to the way in which solar radio emissions have been used to infer the processes taking place in the solar corona.
