Astronomy:Soyuz MS-27

Soyuz MS-27
	Soyuz MS-27 launches to the International Space Station atop a Soyuz-2.1a rocket
Names	ISS 73S
Mission type	ISS crew transport
Operator	Roscosmos
Mission duration	280 days, 9 hours and 40 minutes (in progress); 240 days (planned)
Spacecraft properties
Spacecraft	Soyuz MS-27 No. 758
Spacecraft type	Soyuz MS
Manufacturer	Energia
Launch mass	7,152 kg (15,767 lb)
Crew
Crew size	3
Members	Sergey Ryzhikov; Alexey Zubritsky; Jonny Kim;
Callsign	Favor
Expedition	Expedition 72/73
Start of mission
Launch date	8 April 2025, 05:47:15 UTC
Rocket	Soyuz-2.1a No. K15000-075
Launch site	Baikonur, Site 31/6
Contractor	RKTs Progress
End of mission
Landing date	9 December 2025 (planned)
Landing site	Kazakh Steppe, Kazakhstan
Orbital parameters
Reference system	Geocentric orbit
Regime	Low Earth orbit
Docking with ISS
Docking port	Prichal nadir
Docking date	8 April 2025, 08:57:43 UTC
Undocking date	9 December 2025 (planned)
Time docked	280 days, 6 hours and 31 minutes (in progress)
	; Mission patch; ; From left: Kim, Ryzhikov and Zubritsky Soyuz programme ← Soyuz MS-26 Soyuz MS-28 →

Soyuz MS-27 is a Russian crewed Soyuz spaceflight that launched on 8 April 2025 from Site 31/6 at the Baikonur Cosmodrome, bound for the International Space Station. The spacecraft was launched aboard a Soyuz-2.1a rocket carrying three crew members, Roscosmos cosmonauts Sergey Ryzhikov and Alexey Zubritsky, along with NASA astronaut Jonny Kim.

Mission

The Soyuz MS-27 spacecraft, assembled by Energia, was transported by rail from its manufacturing facility in Korolev, Russia, to the Baikonur Cosmodrome in Kazakhstan, arriving in December 2024. Final testing and processing commenced in mid-January 2025.⁠^[5]

Meanwhile, the components for the Soyuz-2.1a rocket were manufactured by RKTs Progress in Samara, Russia, and shipped by rail to Baikonur, where assembly was underway by the end of January.^[5]

Final spacecraft preparations resumed in early March. On 24 March, both the primary and backup crews conducted a fit check of their Sokol launch and entry suits and participated in familiarization training inside the flight-ready spacecraft. Propellant loading was completed on 25 March, followed shortly by cargo loading. On 27 March, Soyuz MS-27 was mated to its launch vehicle adapter.⁠^[5]

Additional crew training took place on 2 April, as members of Expedition 73 completed their final onboard exercises inside the fully assembled Soyuz MS-27. The following day, the payload section—including the spacecraft—was transported from the processing facility to the vehicle assembly building at Site 31/6, where it was integrated with the Soyuz-2.1a rocket. Integration was completed on 4 April. On the morning of 5 April, the fully assembled launch vehicle was rolled out to the launch pad at Site 31/6.^[2] The rocket was decorated with decals to celebrate the 80th anniversary of the end of World War II.^[6]

Three days later, on 8 April at 05:47:15 UTC, Soyuz MS-27 lifted off atop a Soyuz-2.1a rocket from the Baikonur Cosmodrome as scheduled. After an 8-minute 49-second ascent, the third stage engine cutoff occurred, and the Soyuz MS-27 was released into its initial orbit three seconds later. The spacecraft proceeded with a fast-track rendezvous and successfully docked to the nadir port of the Prichal module at 08:57:43 UTC, just 3 hours, 10 minutes and 28 seconds after launch. The crew entered the station at 09:28 UTC.^[2]

Crew

Prime crew
Position^[1]	Crew
Commander	Sergey Ryzhikov, Roscosmos Expedition 72/73 Third spaceflight
Flight engineer	Alexey Zubritsky, Roscosmos Expedition 72/73 First spaceflight
Flight engineer	Jonny Kim, NASA Expedition 72/73 First spaceflight