Observed Solar Pressure Perturbations of Echo I

Abstract

During the period 13 August to 22 August, day-to-day determinaitions of the average orbital elements of the 100-foot Echo I balloon, based on observations taken at the Jet Propulsion Laboratory's Goldstone tracking station, indicated a decrease in perigee height of 3.0 km/day and an increase in the eccentricity of 0.00038 per day.