Parking Orbit - Examples

Examples

• The Apollo program used parking orbits, for all the reasons mentioned above except those that pertain to geostationary orbits.

• The Space Shuttle missions to the International Space Station did not use parking orbits, for several reasons. The station is in a high inclination Low Earth orbit, where parking orbits are not much help; the shuttle did not have multiple restart capability; and the short launch windows were not a critical problem (another one would occur a day later, due to the orbital geometry).

• On the other hand, when the shuttle launched interplanetary probes such as Galileo, it used a parking orbit to deliver the probe to the right injection spot.

• The Ariane 5 does not use parking orbits. This simplifies the launcher since multiple restart is not needed, and the penalty is small for their typical GTO mission, as their launch site is close to the equator. An upgrade to the second stage (ESC-B) will have multiple restart capability, so future missions may use parking orbits.

• In a literal example of a parking orbit, the Automated Transfer Vehicle (ATV) can park for several months in orbit while waiting to rendezvous with the International Space Station. For safety reasons, the ATV cannot approach the station while a Space Shuttle is docked or when a Soyuz or Progress are maneuvering to dock or depart.