US Space Command Support to
Orbiting Manned Space Flight

Every day, the United States Space Command (USSPACECOM) monitors more than 8,000 man-made objects orbiting the Earth. The command supports manned space flight with data from a worldwide Space Surveillance Network (SSN) of 17 radar and optical sensors. These provide extensive worldwide but not complete global coverage. The sensors are able to monitor an object as small as a baseball in Low Earth Orbit approximately 100 to 600 miles from Earth and as small as a volleyball in Geosynchronous Orbit, approximately 22,300 miles.

USSPACECOM supports manned missions like our Space Shuttle and the Russian Mir Space Station, comparing the orbits of satellites and debris with the orbit of manned spacecraft 36 hours into the future. This support is also provided for satellites which are to be deployed by the shuttle to conduct an experiment or research and then retrieved by the shuttle. Prior to the shuttle launch and any on-orbit maneuvers, the National Aeronautics and Space Administration (NASA) will inform the Space Control Center in Cheyenne Mountain who will in turn check for any possible close approaches in the new flight path 36 hours out. If the orbit of any satellite or debris comes close to the predicted orbit of the Shuttle or Mir, USSPACECOM immediately notifies NASA. If the close approach is to the shuttle, NASA decides whether to maneuver the shuttle to avoid the satellite or debris. If the Mir is involved, NASA will forward the information provided by USSPACECOM to the Russian Space Agency and the Russians will determine the appropriate action.

Also closely supported by USSPACECOM are shuttle missions involving space rendezvous. Prior to the launch, NASA and USSPACECOM analyze the intended path of the shuttle and the object with which it will rendezvous. After the shuttle is in orbit, updated information about the other object’s orbit is provided so a smooth and safe rendezvous can take place. Examples of this would be the shuttle docking with the Mir or the shuttle rendezvousing with the Hubble space telescope.

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