Mir space station. Cosmonauts assembled Mir piece-by-piece during a busy ten-year period beginning in 1986. The station's modules include the voluminous Core, Mir's original 20-ton segment that harbors the crew's living quarters; plus Spektr, a 19-ton science laboratory famous for its 1997 collision with a Progress spacecraft; and the 19-ton Priroda Earth observatory.

Credits - NASA