Calculation of line of site periods between two artificial satellites under the action air drag

In a previous (herein referred to as Ammar, Amin and Hassan Paper [1]) the statement of the problem was formulated and the basic visibility function between two satellites in terms of the orbital elements and time were derived. In this paper the perturbing effect due to drag force on the visibility function were derived explicitly up to O(e⁴), by using Taylor’s expansion for the visibility function about certain epoch. We determine the rise and set times of the satellites through the sign of the visibility function. Numerical examples were worked out for some satellites in order to check the validity of the work.