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Space transport is the use of spacecraft to transport people or cargo through outer space. In human spaceflight, the people transported are the crew who operate the spacecraft, and occasionally passengers. Some cargo carrying spacecraft, like the Progress, have no crew or passengers during their flight and operate either by telerobotic control or are fully autonomous.

Currently, spacecraft most commonly use rocket technology for propulsion. Rocket engines expel propellant to provide forward thrust. Different ranges and types of rockets and other spacecraft have been used (or proposed) for different environments and goals, including:

* expendable launch system
* single stage to orbit
* orbital maneuvering system
* interplanetary travel
* interstellar travel
* intergalactic travel

There are also several non-standard propulsion systems in the works which do not directly rely on rocket propulsion, including solar sails, magnetic sails, plasma-bubble magnetic systems, and using gravitational slingshot effects. For launches from the Earth's surface, several non-rocket launch methods have been proposed, such as launch loops, space elevators and rotovators; but these would be large-scale engineering projects, and many of them require new materials much stronger than any currently known.

* For more types, see spacecraft propulsion.
* For a complete list of space launchers, see the list of rockets.
* For more information on the business of space transportation, see private spaceflight and commercialization of space.

Source:http://en.wikipedia.org/wiki/Space_transport


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