The Soyuz TMA-015M spacecraft that was due to return astronauts back to Earth made an unintentional thruster firing on 9 June 2015 while connected to the International Space Station (ISS). The firing took place at 1527 GMT, apparently during testing of a radio system used in the docking procedure. The thruster firing slowly spun the ISS into an incorrect orientation. NASA has confirmed that this was immediately corrected and that engineers are examining why the firing took place.
Of more concern to NASA and to Roscosmos and ESA was that the Soyuz TMA-015M had been due to return three astronauts on 11 June 2016: ESA’s Samantha Cristoforetti (after her record-breaking 200 day stay), Roscosmos’ Anton Shkaplerov and NASA’s Terry Virts. Their departure had already been delayed by the failure of the Progress M-027M resupply cargo mission which was damaged during its Soyuz 2-1a launch.
Update on 11 June 2015: The three crew have now successfully re-entered and landed.