Safe journey back, Samantha!
This time it seems to be true: the mission of Samantha and her colleagues Terry Virts and Anton Shkaplerov will end 11 June after 199,7 days. Only 8 hours short of 200 days. Wednesday at 16:40, with almost a day in advance, Terry handed over the command of the Space Station to Gennady Padalka.
Thursday is the day of return. It is an early start before they close the hatch behind them once in the Soyuz capsule. This will be at around 8:55 CEST.
At this point a series of checks and tests of their return vehicle will last for a few orbits. Around 12:20 CEST, the three astronauts leave Space Station: it is time for the so-called undocking. The Soyuz “drops its moorings” and starts to fall, moving to a different orbit from the International Space Station. The return journey is effectively nothing more than a fall to the Earth in a controlled manner.
After a few orbits, the most important moment comes: the Soyuz turns the engines on and gives the final push to start its deorbit at around 14:51. It then dives into the atmosphere. Soon after, two of the three modules that make up the Soyuz are discarded: the orbital module and the propulsion module have finished their task and are no longer needed. Only the landing module remains, protected by a heat shield. When it enters the more dense layers of the atmosphere, the module will be akin to a comet on fire, surrounded by glowing plasma.
About 20 minutes from landing, scheduled for 15:43, the spacecraft manoeuvres to reduce its speed. Inside eight minutes it will slow to 800 km/h. 15 minutes before landing, four parachutes open: first two followed by two more in quick succession slowing the capsule to about 30 km / h. Just a second before landing, four small engines light up, like spaceships in science fiction movies, and slow the speed to impact to about 5 km/h.
Despite being a bumpy ride, the astronaut’s is important: to make the reentry softer their seats are moulded to fit them perfectly, like protective nests.
Despite this, there is no point in denying it: the return is no stroll in the park. Shocks, tears, decelerations: astronauts spend the last moments of their mission subjected to violent deceleration, rediscovering the meaning of weight.
Canadian astronaut Chris Hadfield recounted how he was surprised to feel the weight of his tongue and lips, and that even talking felt different after his months in space.
Knowing Samantha, and her communication skills, we are not panicking: she will be able to continue to talk as she did before!
Safe journey home!
Times in Central European Summer Time:
- 8:55 Expedition 43 hatch closing
- 12:18 Undocking command to open hooks and latches
- 12:20 Undocking – Hooks open and physical separation of Soyuz TMA-15M
- 12:23 Separation burn 1, an 8-second burn of the Soyuz engines, .60 m/s
- 12:24 Separation burn 2, a 30-second burn of the Soyuz engines, 1.45 m/s
- 14:51 Deorbit burn lasting 4:35, 128 m/s. Soyuz is now around 12 km from the International Space Station at 401.8 km altitude
- 15:18 Separation of Modules at 140 km altitude
- 15:26 Maximum loads on the astronauts up to five times normal gravity at 36.5 km altitude
- 15:28 Command to open parachutes at 10.7 km.
Two Pilot Parachutes are first deployed, the second of which extracts the drogue chute, slowing the Soyuz down from a descent rate of 230 m/s to 80 m/s.
The Main Parachute is then released, slowing the Soyuz to a 7.2 m/s. The Soyuz descends at an angle of 30 degrees to expel heat, then shifts to a straight vertical descent.
- 15:43 Touchdown after engine firing to slow the Soyuz down to 1.5 m/s around 80 cm above ground.
Landing site: about 145 km southeast of Dzhezkazgan. Landing will occur approximately 1 hour, 34 minutes before sunset at the landing site in Kazakhstan.