The orbit of the European retrievable carrier

An analytical model for the orbits prediction for the EUropean REtrievable CArrier (Eureca) Shuttle-launched free-flying spacecraft is presented, along with calculations for rendezvous maneuvers. The Eureca will transfer to a 450-500 km orbit once deployed from the Orbiter, then return to a lower orbit for retrieval 4-6 mos later. An analytic solution approach for the equations of motion is presented for the case of orbits lower than 1000 km with small eccentricities. Air drag perturbations are modeled, including variation of the aerodynamic cross section, and averaged drag equations of motion are derived. Calculations are presented for the transfer of Eureca from a 300 km to a 400 km orbit using the analytical prediction of orbital decay for earth satellites (APODES) program. Finally, the configuration of a waiting orbit for retrieval by the Shuttle should the Shuttle launch be delayed for one or several days are determined.