several NASA science experiments, and repressurized the remaining modules.

An internal space walk by Tsibliev and Mir 23 Flight Engineer Aleksandr Lazutkin was planned to reconnect power cables to the three undamaged solar arrays, but during a routine medical exam 13 July Tsibliev was found to have an irregular heartbeat. Foale then began training for the space walk, but during one of the training exercises a power cable was inadvertently disconnected, leaving the station without power. On 21