In May 1986, Leonid Kizim and Vladimir Solovyov left the newly opened Mir, crossed 2,500 kilometres to Salyut 7, and returned carrying 350 to 400 kilograms of instruments — the only human voyage ever made from one space station to another

In May 1986, Leonid Kizim and Vladimir Solovyov left the newly opened Mir, crossed 2,500 kilometres to Salyut 7, and returned carrying 350 to 400 kilograms of instruments — the only human voyage ever made from one space station to another

On 5 May 1986, Leonid Kizim and Vladimir Solovyov sealed the hatch of the newest space station in orbit, climbed into Soyuz T-15 and pushed away from Mir with another station waiting roughly 2,500 kilometres ahead. Twenty-nine hours later, they docked with Salyut 7. They would spend 50 days there, carry out two spacewalks, remove 20 instruments weighing between 350 and 400 kilograms, and then fly back to Mir. According to NASA’s Mir Hardware Her…