Abstract: A spacecraft dependent on a non-intrusive servicing vehicle is provided. The spacecraft has a spacecraft body having at least one propellant tank and an actual orbit. The spacecraft body is located in an actual orbit and is adapted to be moved to an intended orbit. A payload is connected to the spacecraft body. A non-intrusive servicing interface is connected to the spacecraft. The servicing interface is adapted to repeatedly removably connect the spacecraft body to the non-intrusive servicing vehicle. The actual orbit of the spacecraft body is adjusted by the non-intrusive servicing vehicle and depends upon substantially periodic adjustments of the actual orbit by the non-intrusive servicing vehicle in order to maintain the parameters characterizing the actual orbit within dead bands specified for the intended orbit.

Abstract: A broadband communication system having a first broadband communication ground station, a second broadband communication ground station, and a satellite constellation. The satellite constellation is used for conducting bi-direction broadband communication between the first broadband communication ground station and the second broadband communication ground station. At least one satellite of the satellite constellation has an inclined eccentric orbit in a first orbit plane. The satellite constellation is disposed in orbit so that when observed from a predetermined ground observation point a number of satellites, including the at least one satellite, in the constellation appear to follow a substantially common path which extends through a predetermined active zone. The number of satellites moving along the common path is such that the predetermined active zone has one satellite from the number of satellites continuously located therein.

Abstract: A method for operating a spacecraft comprising the steps of placing the spacecraft in a first orbit, changing orbital altitude of the spacecraft to transfer the spacecraft from the first orbit to a second orbit, changing an orbital plane of the spacecraft from an initial orbital plane to a different orbital plane, and changing orbital altitudes of the spacecraft to return to the spacecraft from the second orbit to the first orbit. The second orbit is at a different altitude than the first orbit of the spacecraft. The orbital altitude change placing the spacecraft in the second orbit and the orbital plane change are performed at substantially the same time.

Abstract: A system for supplying a space station or satellite comprises a low cost expendable single-stage to orbit launch vehicle having a moderate reliability in the range of about 0.5 to 0.8 for launching a payload of consumable items to low earth orbit. For propulsion, the launch vehicle includes a pressure-fed rocket engine, preferably with a nozzle for aiming products of combustion in a direction away from the launch vehicle and having a fixed orientation relative to the launch vehicle. A pressurant tank contains an inert pressurant gas under pressure. A conduit system serves to introduce the inert pressurant gas from the pressurant tank to a fuel tank and thence to the rocket engine and also to introduce the inert pressurant gas from the pressurant tank to an oxidizer tank and thence to the rocket engine for combustion with the fuel.

Abstract: A control method and improved equatorial-normal body-stabilized spacecraft that operates in an inclined orbit. The control method controls pointing of payloads (communication antennas and instruments) and solar arrays disposed on the spacecraft. The method controls the spacecraft to provide Earth-pointing payloads and sun-pointing solar arrays so that the spacecraft body and solar arrays each rotate only around a single axis, a pitch axis of the spacecraft.

Abstract: A man-made satellite (1) traveling in an elliptical orbit. The orbit has five or six daily apogees, which are positioned above the same longitudes of the earth at substantially the same local time-of-day for each day of the year. The longitudes and times-of-day can be preselected subject only to the proviso that they be equispaced. The apsidal rotation rate in inertial space (ARRIS) of the orbit is substantially equal to the mean rate at which the earth revolves about the sun. The orbit is preferably equatorial, in order to simplify ground tracking and to maximize the impact of the apsidal rotation.