Expedition 50 completed at ISS !

Yesterday three new members of Expedition 50: Peggy Whitson (NASA), Thomas Pesquet (ESA) and their pilot and Commander Oleg Novitskiy (Roscosmos) reached friendly interior of the International Space Station after almost two days and 34 orbits of space journey inside Soyuz MS-03.

Soyuz MS-03 with three crew members finally reached International Space Station after lasting two days chase filled with scheduled tests of MS-03 spacecraft. These test campaign begun with first mission of Soyuz MS on July 7, 2016 and will last until Roscosmos will  manage to verify every modified system of Soyuz in flight. This time tests covered among others attempt of manual steering with utilization of DPO thrusters and receiving uplink of data sent by ground radio  station using onboard  S-band transponder. Flight of the MS-03 was finished with short rendez vous and as usual was done automatically by onboard computer of vehicle and other on ISS. Maneuver and docking were supervised by Mission Control Center in  Korolev under Moscow and Johnson Space Center on Space Center in Houston TX.

Docking started from initiating automated rendezvous sequence at 19:40 UTC on Saturday with distance between MS-03 and ISS at 80 km. Soyuz was still below Station remaining on 400 km orbit and to reduce distance, it was necessary to start SKD thruster to increase chase speed. On the other side, different systems inside ISS were turned off to avoid any problems or jamming of navigational docking computer of Soyuz.  Next, voice communication between Soyuz and ISS was started, just before switching on Kurs (ISS) and Kurs-NA navigational systems for docking. Later, SKD burns gradually helped in reducing distance until 1000 m point; from that moment Soyuz started flyaround maneuver using DPO thrusters (DPO thrusters are controlled by Attitude Control System and are able to provide thrust of 130 N burning Unsymmetrical Dimethylhydrazine) to align with Rassvet nadir docking port. After that phase, Soyuz reached 200 m point and performed roll maneuver to set solar arrays on the correct position for docking. Finally, Commander Oleg Novitskiy decided to start docking. Kurs-NA and Attitude Control System gently trimmed DPO thrusters to start getting close to docking port with speed of 0.8 m/s and reduce it for 0.2 m/s just before touching rim of the docking port at  21:58 UTC during flying over Brazil.

After performing leak tests and general safety inspection, members of Expedition 50 opened hatch at 00:40 on Sunday, November 20. Peggy Whitson, Oleg Novitskiy and Thomas Pesquet entered ISS and joined Commander Shane Kimbrough (NASA), Sergey Ryzhikov and Andrey Borisenko of the Roscosmos. They will spent together rest of planned 178 days of Expedition 50, until 26 th February 2017, when Soyuz MS-02 will return to Earth.