Crew members of Expedition 38 have safely returned to Earth, their Soyuz capsule setting down in Kazakhstan on Mar. 10 at 11:24 p.m. EDT. The astronauts and cosmonauts spent 116 days in space, carrying out a wide range of experiments and successfully executing multiple space walks.

Expedition 38 consisted of six astronauts and cosmonauts, officially coming to an end with Oleg Kotov, Mike Hopkins and Sergey Ryazanskiy undocking from the International Space Station (ISS) to begin the short journey home. The remaining three crew members – Flight Engineer Mikhail Tyurin, Richard Mastracchio and now-Commander Koichi Wakata, will stay aboard the International Space Station forming the crew of Expedition 39.

Expedition 38 at work

The first space walk of Expedition 38 took the form of flight engineer Mike Hopkins teaming up with Rick Mastracchio to replace a faulty ammonia cell that was threatening to undermine the ISS's cooling system. The team failed to complete the work on the original Dec. 1, 2013 SG space walk, forcing the pair to undertake further walks outside the station including one on Christmas eve.

For Russian cosmonauts Oleg Kotov and Sergey Ryazanskiy, their first extra-vehicular activity (EVA) on Feb. 7 represented a first for mankind as they completed the first outer space section of the Olympic relay. The torch was returned to Earth the following day, and on Feb. 7 was used to open the 2014 Winter Olympic Games in Sochi.

Astronaut Mike Hopkins, taken during the Dec. 24 space walk (Photo:NASA)

Another pair of EVAs carried out by Kotov and Ryazanskiy involved the installation of a high resolution and medium resolution camera that will be used by the Canadian company UrtheCast to give subscribers a high-quality near-live stream of planet Earth from space.

Whilst it was the first mission for both Mike Hopkins and Sergey Ryazanskiy, expedition commander Oleg Kotov completed his third stretch aboard the International Space Station. Kotev has notched up an impressive 532 days in space, including just under 37 hours outside the station in his Russian-build Orlan spacesuit.

However, not all of the expedition's work took place outside of the space station. The crew also undertook a wide variety of research projects within the ISS, ranging from studying the behavior of liquid movement in microgravity to experiments put forward by students.

A short drop and a gentle stop

The members of Expedition 38 undocked from the Poisk module of the International Space Station at 8:01 p.m. EDT to begin their three-and-a-half-hour return journey, culminating in a gentle touchdown on the flat steppe of Kazakhstan.

The trio returned to earth via a Soyuz TMA spacecraft, which is comprised of three sections – the Orbital Module, the Descent Module and the Instrumentation/Propulsion Module. Being of no further use during descent, the crew jettisoned the orbital and propulsion modules, allowing them to safely burn up in the atmosphere, leaving only the descent module to protect the crew on the final leg of their journey.

Three hours after undocking with the crew at 400,000 ft (121,920m) above the Earth, the descent capsule hit the Entry Interface (the point at which the Earth's atmosphere thickens), creating friction which heats up the outer hull. A mere eight minutes later, the capsule was hurtling towards the ground traveling at 755 feet per second (230 m per second) with the minds of the crew fixed on one vital component – the parachutes.

Fifteen minutes before touchdown, the Soyuz capsule released two pilot parachutes with a drogue chute following immediately after. The final chute to deploy was the main parachute – measuring 10,764 sq ft (3275 sq m), it has a larger surface area than two basketball courts combined.

On the left sits Sergey Ryazanskiy, in the center is Commander Oleg Kotov, and to the right is Flight Engineer Mike Hopkins (Photo: NASA/Bill Ingalls)

The combined effect of the parachutes is to slow the capsule to a more leisurely 24 feet per second. Finally, mere feet off the ground, six small engines located at the bottom of the capsule fired, further softening the landing.

Whilst the descent itself went off without a hitch, the recovery was hampered by weather that grounded the majority of the usual recovery aircraft, with only a few of the usual fleet of helicopters and recovery aircraft taking to the skies.

The members of Expedition 38 will be replaced by Expedition 39/40, consisting of crew members Steve Swanson, Alexander Skvortsov and Oleg Artemyev. The new crew are slated to launch Mar. 25, on a Soyuz TMA-12 spacecraft from Baikonur Cosmodrome, Kazakhstan.

The video below is a recording of the historic space walk that took the Olympic torch into space.

Source: NASA

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