Soyuz TM-8 was the eighth mission and the fifth long-duration expedition to Mir space station. The mission began on September 5, 1989, 21:38:03 UTC, launching Commander Alexander Viktorenko and Flight Engineer Aleksandr Serebrov into orbit. They docked with Mir two days later. During their stay there, cosmonauts performed five EVAs, various station maintenance tasks, and carried out scientific experiments in medicine, geophysics, space technology, earth observation, astronomy etc.
The crew returned after 166 days in orbit, landing safely back on Earth on February 19, 1990, 04:36:18 UTC.