Soyuz TM-9 was the ninth expedition to the Russian Space Station Mir.
During docking, cosmonauts aboard Mir noticed that three of the eight thermal blankets (layers of foil vacuum-shield insulation) on the decent module of the approaching Soyuz-TM 9 spacecraft had come loose from their attachments near the heat shield, yet remained attached at their top ends. The main concern was that the capsule might cool down, permitting condensation to form inside and short out its electrical systems. There was also fear that the blankets might block the infrared vertical sensor, which oriented the module for re-entry.

Three other areas of concern emerged: that the explosive bolts binding the service module to the descent module might fail to work after direct exposure to space, that the heat shield might be compromised by direct space exposure, and that an EVA to repair the blankets might cause additional damage. Consideration was given to flying Soyuz TM-10 with one cosmonaut aboard as a rescue mission. During an EVA, the cosmonauts folded back two of the three blankets and left the third alone. During reentry, the cosmonauts ejected both the orbitalmodule and the service module simultaneously in an effort to minimize the chances that a blanket could snag. Normally the orbital module went first. The descent module suffered no damage as a result of its prolonged exposure to space conditions. Reentry occurred as normal.

The long-awaited, much-delayed Kristall module arrived at Mir's front port on June 10, 1990 and was relocated to the lateral port opposite Kvant2 on the next day. This restored the equilibrium of the complex, which had been asymmetrical since Kvant2 was placed at a lateral port in December 1989. The Kristall module was launched May 31, 1990. It had aborted its first docking attempt on June 06, 1990 due to an attitude control thruster failure. Delays in launch and docking affected Aleksandr Balandin and Anatoli Soloviyov, who were scheduled to return to Earth at the end of July 1990. Their mission was extended 10 days to permit them to activate Kristall's systems, and to accommodate the EVA to repair the loose thermal blankets on Soyuz TM-9.

Kristall was the third addition to the Mir core vehicle and was primarily designed to investigate materials processing technologies in the space environment. The module also supported biological, Earth observation and astrophysical research. It had a mass of 19.6 tons, a length of 11.9 meter, and a maximum diameter of 4.35 meter.

Kristall was divided into an instrument/cargo and instrument/docking compartment, with 61 cubic meters of total pressurized volume. The instrument/cargo compartment held materials processing and biological experiments. The instrument/docking compartment held other investigations as well as a pair of docking ports. One of these ports was originally intended to support visits by the later cancelled Buran orbiter.
Originally equipped with 2 solar panels (72 sq. m total area) that provided up to 8.4 kW (one moved to Kvant1 in 1995). Unlike the other solar panels on the Mir complex, these could be folded or unfolded as a function of electrical power requirements. A 360 A-hour NiCd battery system provided energy storage. 2 3.9 kN main engines (NTO/UDMH) and clusters of 400N attitude control thrusters were used during the original docking process.

The scientific payload consisted of:
Krater 5, Optizon 1, CSK-1/Kristallizator semiconductor materials processing furnaces; Zona 2/3 materials processing furnaces; Glazar 2 UV telescope - cosmic radiation studies; Priroda 5 Earth resources camera system - consisted of 2 KFA-1000 film cameras; Svet plant cultivation unit; Mariya magnetic spectrometer; Marina gamma ray telescope; Buket gamma ray spectrometer; Granar astrophysics spectrometer; Ainur electrophoresis unit.