The purpose of this experiment was to obtain new and important data to assist in evaluating the ionization effects of EUV radiation in the upper atmosphere. In early 1979, ECOM-721 was launched aboard the P78-1 Air Force satellite, and took millions of spectra to achieve this goal over the course of the year. The spectrograph covered the 200 Å to 1300 Å spectral region with selectable 5 Å or 10 Å resolution.
This band of the spectrum is uniquely suited to the study of a variety of atomic and molecular processes. These processes occur in or around the upper atmosphere because the most abundant species resonate at these frequencies.
The data verified conclusively that it is a region rich in spectral features, including lines of O II . Furthermore, precise and unambiguous results from these and many more observations crucially depended on assumptions of what spectral features were missing. ECOM-721's design corrected this situation.
The measured intensities, based on individual EUV features, were of special significance. Through detailed study, especially as a function of location and time, many exciting new areas of research were found. Some of these are included in the following primary objectives:
Secondary objectives include:
