Kosmos 186 and Kosmos 188 were two uncrewed spacecraft from the Soviet Union that achieved the first fully automated space docking in the history of space exploration on October 30, 1967. Kosmos 186 was launched first on October 27, 1967, followed by Kosmos 188 three days later. With Kosmos 186 taking the active role in the docking process, the two spacecraft successfully docked just 62 minutes after the launch of Kosmos 188, the passive target spacecraft. The IGLA system onboard Kosmos 186 automatically managed the mutual search, approach, mooring, and docking. After 3.5 hours of joint flight, the spacecraft separated following a command sent from Earth and continued to orbit independently. Both spacecraft made a soft landing in a predetermined region of the Soviet Union—Kosmos 186 on October 31, 1967, and Kosmos 188 on November 2, 1967.
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| A launch cover for Kosmos 186, featuring a Tartu postmark dated October 28, 1967. |
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| A landing cover for Kosmos 188, featuring a Tartu postmark dated November 3, 1967. |
The automatic docking mission showcased a new capability for the Soviet Union that would prove valuable for their later Salyut and Mir space station programs. This mission also demonstrated the feasibility of launching smaller components and assembling them in space, thereby reducing the necessity for excessively large rockets for major projects like a space station.
(Reference from
Kosmos 186 and Kosmos 188)
