An analysis of occultation observations of the Galilean satellites of Jupiter and comparison with theories

Historic occultation data on Galilean satellites were evaluated for usefulness for determining the proper motions of the satellites in conjunction with current, higher accuracy data. The database covers 4411 observations from 1836-1972 and includes observations from 44 different sites. The time residuals were calculated by two techniques which considered the time when the center of the satellite is on the conical surface resting on the planet with the apex on the earth. Errors were the same order of magnitude as obtained with visual eclipse data. Thus, the historic occultation data can be used in the same way as the historic eclipse data.