[image-51]The astronauts and cosmonauts of the Expedition 38 crew supported medical and material science research Wednesday while three of their crewmates prepared for the trip home after nearly six months in space.
Just after the crew’s usual wakeup time at 1 a.m. EST, Flight Engineer Mike Hopkins got an early start on the workday by providing body samples for the Microbiome study, which takes a look at the impact of space travel on the human immune system and an individual’s microbiome -- the collective community of microorganisms that are normally present in and on the human body. In addition to providing data that will keep future crews healthy, findings from this study could benefit people on Earth who work in extreme environments and further research in the detection of diseases, alterations in metabolic function and deficiencies in the immune system.
Following the crew’s daily planning conference with flight control teams around the world, Flight Engineers Koichi Wakata and Rick Mastracchio conducted another round of medical exams for the Ocular Health investigation. Flight surgeons have noted that there have been vision changes in up to 50 percent of astronauts returning from long-duration spaceflight. As NASA works toward sending humans on longer voyages deeper into space than ever before, researchers want to learn more about the root causes of this change in eyesight and develop countermeasures to minimize the risk. With guidance from the Ocular Health team on the ground, Mastracchio assisted Wakata with a cardiac scan. Mastracchio then performed an ultrasound scan on Wakata’s eyes.
Hopkins meanwhile joined his colleagues Commander Oleg Kotov and Flight Engineer Sergey Ryazanskiy for some departure preparations as they gear up for the return to Earth after nearly six months in space. The three checked out the protective Kentavr garments they will wear under their Sokol launch and entry suits during the trip back to Earth to ease the transition back into the full-force of Earth’s gravity. Kotov, Ryazanskiy and Hopkins are scheduled to undock from the station Monday at 8:02 p.m. EDT aboard their Soyuz TMA-10M spacecraft and land southeast of the town of Dzhezkazgan in Kazakhstan at 11:24 p.m. (9:24 a.m. Tuesday, Kazakhstan time), wrapping up 166 days in space for the trio.
Ryazanskiy also spent several hours packing items in the Soyuz, while Kotov prepared a small HD camera to record activities during the Soyuz descent.
Mastracchio and Hopkins later teamed up to review the procedures for removing and replacing the Water Recovery System’s catalytic reactor. Afterward, Mastracchio went off to gather tools and hardware so that he and Hopkins can begin that task on Thursday. Part of the station’s Environment Control and Life Support System, the Water Recovery System recycles condensation and urine into drinkable water. Or as former station resident Don Pettit once put it, “It turns yesterday’s coffee into today’s coffee.”
Wakata spent much of the afternoon inside the Kibo module preparing the Fluid Physics Experiment Facility for the next iteration of the Marangoni experiment. The Japan Aerospace Exploration Agency astronaut cleaned the experiment hardware and replaced components. Marangoni convection is the flow process that results from the difference in surface tensions where a liquid and a gas come together. By studying this process in microgravity, researchers hope to uncover fundamental properties that could improve the production of semiconductors and optical crystals and contribute to various micro-fluid handling techniques, such as those used in DNA examination and clinical diagnostics.
[image-78]Wakata, Hopkins and Mastracchio took a break from their work to talk with Josh Zepps of the Huffington Post and Jonathan Bloom of KGO-TV in San Francisco. The three astronauts discussed life and work aboard the orbiting complex and their participation in social media, including the frequent and dramatic photos of Earth from space which they post to Twitter.
Hopkins rounded out his day removing lockers from one of the eight EXPRESS experiment racks aboard the station and collecting more samples for the Microbiome study. Hopkins also spoke with students at Rock Bridge Elementary School in Columbia, Mo., via the station’s ham radio.
On the Russian side of the complex, Flight Engineer Mikhail Tyurin prepared the Kaplya-2 hardware for stowage. Kaplya-2 studies the fluid motion and heat transfer of monodisperse drop flows in space. Afterward he downloaded data from an earthquake-monitoring experiment known as Seismoprognoz.
Tyurin also collected dosimeter readings from the Matryoshka experiment. Named after the traditional Russian nesting dolls, Matryoshka analyzes the radiation environment onboard the station.
Kotov spent some time examining chemical luminescent reactions in the Earth’s atmosphere for the Relaxation experiment. The commander also performed routine maintenance on the life-support system in the Zvezda service module.
[image-94]The departure of Kotov, Hopkins and Ryazanskiy on Monday will mark the end of Expedition 38 and the beginning of Expedition 39 under the leadership of Wakata, the first Japan Aerospace Exploration Agency astronaut to command the station. Kotov will pass the helm to Wakata during a Change of Command ceremony slated for 4:50 a.m. Sunday. Wakata, Mastracchio and Tyurin, who arrived at the orbiting complex Nov. 7, will remain aboard the station until mid-May.
Meanwhile the three flight engineers who will return the station’s crew to its full six-person complement are in the final month of preparations for launch. NASA astronaut Steve Swanson and Russian cosmonauts Alexander Skvortsov and Oleg Artemyev completed the second of two days of final qualification exams Wednesday at the Gagarin Cosmonaut Training Center in Star City, Russia. On March 13, they will fly to the launch site in Baikonur to begin the final phase of training for their launch on March 25 aboard the Soyuz TMA-12M spacecraft.