The
Progress spacecraft is a modification of the
Soyuz spacecraft. Operating unmanned, it is used to deliver fuel and supplies to orbiting
space stations. Of the three modules of Soyuz, the service module is relatively similar, the descent module is replaced by a fuel storage module and the orbital module is used to carry supplies. The fuel can be either pumped to the space station or used to fuel the module's own engine, allowing it to provide thrust to the space station to boost its orbit. Once the supplies have been unloaded from the spacecraft, it is typically filled with rubbish and sent to burn up in the Earth's atmosphere.
The first Progress spacecraft docked at Salyut-6. An improved version, the Progress M, was introduced in 1989 to service Mir. The third variant, the Progress M1, has increased fuel storage capacity and is now used for the International Space Station.
The Progress spacecraft are manufactured by the S.P. Korolev Rocket and Space Corporation Energia.