Station Extravehicular Activity
for Hands-On Construction in Outer Space
Mission Specialists Jerry Ross and James Newman work together
during the first International Space Station assembly mission.
The Zarya module solar array is in the background.|
Recognizing the challenge
and complexity of building the International Space Station, NASA
has made a concerted effort for more than a decade to develop
and flight test the spacewalk equipment needed; refine spacewalk
training procedures; and build spacewalk, or extravehicular activity,
experience among astronauts, engineers and flight controllers.
Since 1991, more than a dozen "practice" spacewalks have been
conducted during space shuttle flights as part of NASA's preparations.
In addition, three servicing missions for the Hubble Space Telescope
have helped prepare for the intricate work needed to build the
station. Many of the astronauts who gained experience during these
"practice" spacewalks are bringing that knowledge to bear during
spacewalks in the station's orbital assembly.
The flight-testing of
EVA equipment designed for use aboard the International Space
Station began on the first spacewalk NASA conducted after the
space shuttle's return to flight following the Challenger accident.
On shuttle mission STS-37 in April 1991, Astronauts Jerry Ross
and Jay Apt performed a spacewalk to test a Crew and Equipment
Translation Aid cart designed for use in assisting astronauts
to move about the football field-long truss of the completed station.
Two such carts are now planned for launch to the station during its
Since 1991, other spacewalks
have evaluated new tethers, tools, foot restraints, handling large
masses, a jet pack "life jacket," spacesuit enhancements and even
the planned station lettering and toolboxes.
To prepare for International
Space Station assembly in earnest, NASA announced the first International
Space Station EVA assembly crew, Ross and Jim Newman on STS-88,
in August 1996. In June 1997, five more crews of station assembly
spacewalkers were named to complete the first six shuttle assembly
missions, some of them more than two years ahead of their scheduled
mission, much earlier than is traditional. The early naming of
crewmembers has allowed the astronauts additional time to train
for their complex and crucial missions.