Response of the neutral particle upper atmosphere to the solar eclipse of 7 March 1970.

Results of soundings with a series of five pitot probes launched in conjunction with the solar eclipse of Mar. 7, 1970. Three soundings were programmed to occur at 40, 80, and 100% obscuration of the sun (at 100 km) during a 42-min period. The remaining two soundings were made 24 hr before and after the eclipse. The five soundings yielded neutral particle pressure, temperature, and density profiles over the altitude regime from 30 to 125 km. Below 95 km, the three density profiles resulting from the eclipse day launches had an average deviation of less than 1.5%. Above 95 km, density changes of up to 20% were observed. Such changes in density are comparable in magnitude to those normally observed over a period of several hours. On Mar. 10, 1971, three additional pitot probes were launched at times identical to those of the 1970 eclipse day. Comparison of the two sets of data should provide for a more objective analysis regarding atmospheric response to solar input.