Taking a Walk

Tomorrow, Wednesday, August 3, Russian cosmonauts Sergei Volkov and Alexander Samokutyaev will be conducting a six-hour spacewalk outside the International Space Station.  The objectives include maintenance and scientific tasks, and the launch of a microsatellite devoted to the 50th anniversary of Yuri Gagarin's historic space flight in 1961.

According to NASA and Roscosmos (the Russian Federal Space Agency), this will be the first EVA for Samokutiaev, and the third for Volkov.  Both men are flight engineers for Expedition 28 on the ISS, and Volkov served as the commander for Expedition 17 in 2008.  The spacewalk itself will be broadcast on NASA's web site starting at 9:00 a.m. August 3, those interested can find further information here (LINK)

Among the tasks facing the duo tomorrow include deploying a 57-pound prototype satellite known as "ARISSat-1." The eductational satellite can carry up to four student experiments at one time, and the results can be broadcast to Earth via radio waves.  The prototype currently carries one experiment, a pressure sensor from Kursk University in Russia, which will measure atmospheric pressure.  It will also broadcast greetings in various languages and messages commemorating Yuri Gagarin's spaceflight.  Additionally, it will serve as a spaceborne utility for ham radio operators.  The satellite was prepared and initialized during the course of last week.

Astronauts conducting EVAs (extravehicular activities) must be extremely careful; although they may not be moving much relative to their craft (such as the ISS), they are still travelling extremely rapidly.  The ISS and astronauts conducting operations on and around it travel approximately seventeen thousand miles per hour in a constant free fall, orbiting the earth about every 90 minutes.  For this reason, there are many handles all around the exterior of the ISS that astronauts can hook harnesses around to allow them to work safely.

The other primary task of the cosmonauts will be the transport of an external cargo boom around the exterior of the ISS.  The boom being moved, STRELA-1, will be transported using a second boom, STRELA-2.  It will be moving from the module Pirs to the module Poisk.  Both modules are docking bays for Soyuz and Progress spacecraft, though Poisk was only launched in November 2009 compared to September 2001 for Pirs.  The purpose of this relocation is to retrieve an experiment named "Biorisk" from the airlock of Poisk and mount it on an external handrail on Pirs.  Biorisk examines effects bacteria and fungus on materials that could be used in spacecraft construction.

The crew members of Expedition 28 have performed a combined 127 spacewalks on and around the space station.  Expedition 28 will continue work on a total of 111 different experiments.  These experiments are wide and varied, ranging from tests on how human-like robots perform in microgravity conditions to stress tests of complex materials such as high-tech aluminum alloys or Shape Memory Foam in microgravity.  Those interested in the further exploits of Expedition 28 can visit NASA's official page, which contains many facts, photos, and news about current and upcoming activities.