The VBK-Raduga capsule was a reentry capsule that was used for returning materials to Earth's surface from the space station Mir. They were brought to Mir in the Progress-M cargo craft's dry cargo compartment. For return, the capsule would be substituted for the Progress' docking probe before it left the space station, and then after the Progress-M performed its deorbit burn, the capsule was ejected at 120 km altitude to reenter the atmosphere independently. It would then parachute to a landing area in Russia.^[1]

VBK-Raduga
МКБ-Радуга
NASA illustration of a VBK-Raduga ballistic return capsule during final descent to Earth.
Type	Reentry capsule
Specifications
Dimensions	1.5m long, 60cm diameter
Dry mass	350kg
History
Launched	from Baikonur Cosmodrome
First flight	September 27, 1990
Last flight	April 9, 1995

Each Raduga was about 1.5 m long, 60 cm in diameter, and had an unloaded mass of about 350 kg. It could return about 150 kg of cargo back to Earth. Use of the Raduga reduced the Progress-M's cargo capacity by about 100 kg, to a maximum of about 2400 kg.^{[citation needed]}

The European Space Agency studied a very similar system called PARES (Payload Retrieval System), for use in combination with the Automated Transfer Vehicle.^[2]