Space station trio returns to Earth in Soyuz MS-04
Three members of Expedition 52 returned to Earth inside their Soyuz MS-04 spacecraft. The landing took at 9:21 p.m. EDT Sept. 2 (7:21 a.m. Kazakh Time / 01:21 GMT Sept. 3), 2017, in Kazakhstan.
Returning were NASA astronauts Peggy Whitson and Jack Fischer, as well as Russian cosmonaut Fyodor Yurchikhin. The latter two have been in space since April 2017, while Whitson has been living aboard the outpost since November 2016 – nearly 10 months.
Their journey back to Earth began at 2:41 p.m. EDT (18:41 GMT) Sept. 2, 2017, when the hatches between the spacecraft and space station were closed. Several hours later, at 5:58 p.m. EDT (21:58 GMT), Soyuz MS-04 undocked from the ISS.
When the spacecraft was about 66 feet (20 meters) from the outpost, its thrusters fired to push the spacecraft away faster. Then, some 90 seconds later, a second departure burn was performed to push the vehicle out of the station’s 656-foot (200-meter) Keep-Out Sphere.
The two vehicles continued to separate over the next several hours until they were several miles apart and the Soyuz’ orbit was in line with the landing zone. Then the spacecraft pointed its main SKD engine in the direction of travel to perform a 4-minute, 39-second deorbit burn. This occurred at about 8:29 p.m. EDT (00:29 GMT Sept. 3) to slow the vehicle down by about 420 feet (128 meters) per second.
Several minutes before making contact with Earth’s upper atmosphere, the three modules of the Soyuz – the Orbital Module, the Descent Module, and the Service Module – separated. Only the Descent Module with the crew is designed to survive re-entry.
The Soyuz began skirting the atmosphere at nearly 5 miles (8 kilometers) per second just before 9 p.m. EDT (01:00 GMT) while at an altitude of about 62 miles (100 kilometers).
About seven minutes later, the capsule slowed down to about 1.4 miles (2.2 kilometers) per second. At this point, the crew was experiencing their maximum gravity load of about 4.5 times the force of Earth’s gravity.
Once the atmosphere slowed the capsule down enough, a series of parachute deployments occurred starting with the release of pilot chutes to pull the drogue chute out. This occurred at an altitude of just over six miles (10 kilometers) while traveling some 700 feet (200 meters) per second.
The drogue chute slowed the capsule to about 262 feet (80 meters) per second before the single main parachute was deployed. Its 10,764-square-foot (1,000-square-meter) surface area slowed the capsule to a reasonable 21 feet (6.5 meters) per second.
Throughout the next 10 minutes of descent, the spacecraft and crew began preparing for touchdown. First, the heat shield was jettisoned to reveal the Soft Landing engines. Next, the cabin pressure was equalized with the outside pressure. Finally, the Kazbek crew seats were moved slightly upward relative to the horizon to help absorb the shock of landing.
About one second before touchdown, the Soft Landing engines ignited in a momentary burst to cushion the final three feet (about one meter) of the crew’s journey home.
The Soyuz was pulled onto its side by its parachutes, a normal occurrence. Minutes after landing, search and recovery teams in helicopters and all-terrain vehicles rushed to the capsule to begin extracting the crew. First out was Yurchikhin, as he was in the center seat. Next was Fischer and then Whitson.
Each was carried to lawn chair-like couches, given water, and allowed to call family members. Soon after, the trio were carried into a nearby medical tent for a multi-hour post-landing evaluation.
Next, they will be flown to nearby Karaganda, Kazakhstan, where Whitson and Fischer will part ways with Yurchikhin. The former two will travel back to Houston by way of Cologne, Germany, while the latter will travel to Moscow.
Yurchikhin completed his fifth mission, bringing his on-orbit duration total to 673 days – seventh on the all-time space endurance list. Additionally, he has completed nine spacewalks over his career, bringing his total to 59 hours, 28 minutes.
Fischer completed his fifth mission. During his 136-days in space, he ventured outside the outpost on two spacewalks for a total EVA time of 6 hours, 54 minutes.
Whitson’s 288-day mission brings her cumulative total to 665 days over three missions – eighth on the all-time space endurance list and more than any other American. Over her career, she has performed 10 spacewalks lasting a total of 60 hours, 21 minutes – third on the list of cumulative spacewalk time.
Whitson launched into orbit in Soyuz MS-03. Because Russia decided to reduce its regular crew size from three to two, Soyuz MS-04 only launched with Yurchikhin and Fischer. As such, Whitson was granted a three-month mission extension and was able to use the empty seat for the return journey home.
Remaining aboard the ISS as Expedition 53 are NASA astronaut Randy Bresnik, Russian cosmonaut Sergey Ryazanskiy, and European Space Agency astronaut Paolo Nespoli. They launched to the outpost on July 28 in Soyuz MS-05 and will land in December 2017.
In just 10 days, three more people will launch to the space station. On Sept. 13, 2017, Soyuz MS-06 will send Russian cosmonaut Alexander Misurkin and NASA astronauts Mark Vande Hei and Joe Acaba on a six-hour trek to rendezvous and dock with the outpost. They will remain there until February 2018.
Video courtesy of NASA TV
Derek Richardson has a degree in mass media, with an emphasis in contemporary journalism, from Washburn University in Topeka, Kansas. While at Washburn, he was the managing editor of the student run newspaper, the Washburn Review. He also has a website about human spaceflight called Orbital Velocity. You can find him on twitter @TheSpaceWriter.