International Space Station
The International Space Station will be a permanent laboratory
for human-monitored long term research in the unique environment
of Earth-orbital space, an environment that cannot be duplicated
on Earth for long duration experiments. Research at the station
will focus on two key areas: life sciences and materials sciences.
Life science research is expected to lead to a clearer understanding
of basic processes to provide a foundation for development of
advanced medications for improved human health care. Material
research offers promise of improved metals, composites and plastics
for significant advances in technologies for communications,
transportation and a broad range of industrial processing operations.
Completed early in 1996 was the Boeing-built structure for
the U.S. Laboratory Module, a key element of the International
Space Station. The aluminum module is 28 feet long and weighs
three tons.
The International Space Station draws upon the resources and
scientific/technological expertise of 13 cooperating nations,
including the U.S., Canada, Japan, Russia and nine nations of
the European Space Agency (Belgium, Denmark, France, Germany,
Italy, Norway, Spain, The Netherlands and the United Kingdom).
The prime contractor is The Boeing Company and the principal
subcontractors are McDonnell Douglas Corporation and the Rocketdyne
Division of Rockwell International.
While the Phase I flight program was under way in 1995/96,
manufacturers were turning out the first hardware components
of the space station. Among major segments completed in 1995
were two Boeing-built nodes (Node 1 and Node 2). The nodes will
serve as connecting passageways between modules. Node 1 will
be the first U.S.-built hardware delivered to orbit.
Also built by Boeing is the structure for the U.S. laboratory
module where astronauts will perform continuous scientific research;
it was delivered early in 1996.
Phase II of the space station program, construction in orbit,
begins in November 1997 with the launch on a Russian Proton vehicle
of the FGB functional cargo block. The FGB is a 21-ton element,
built in Russia but purchased by the U.S., that will provide
attitude control and propulsion during the early assembly operations,
plus solar power and berthing ports for additional modules.
The interim International Space Station will look like this.
In the right foreground is the U.S. Laboratory Module and the
station's airlock. In the center of the horizontal string of
modules is the FGB energy block. The solar power array at top
is one of four that will provide power for the complete station.
Below the tower is the Russian-built Universal Docking Module
and, at bottom, one of two crew transfer vehicles.
A month later, Node 1 will be delivered by the Space Shuttle
and attached to the FGB. In May 1998, the embryo space station
will grow with the addition of the Proton-boosted Russian Service
Module, which provides life support and habitation facilities,
utilities and thrusters. Shortly thereafter, in May 1998, the
crew transfer vehicle-a Russian Soyuz TM capsule-will be joined
to the station. In June 1998, the first three-person crew will
begin its orbital stay.
Further additions to the expanding station in the latter part
of 1998 and early 1999 will include one of the four U.S. solar
array modules, which will provide about 23 kilowatts of power;
segments of the central truss; the U.S. Laboratory Module; the
Canadian-built mobile servicing system; the Russian Universal
Docking Module; and the equipment for outfitting the U.S. Laboratory
Module. With Shuttle delivery and attachment of an airlock in
the spring of 1999, Phase II officially comes to a close.
In Phase III, the International Space Station will progress
gradually to its ultimate status as a fully operational permanent
orbital research facility. Among key additions to the core configuration
are the remaining modules of the U.S.-built solar array; the
Japanese Experiment Module (JEM), to be delivered in 2000; and
the U.S. habitation module (February 2002), which contains the
galley, toilet, shower, sleep stations and medical facilities.
A view of the International Space Station in its final configuration
with a Space Shuttle Orbiter docked at the fore port. The cylinder
near the Orbiter's nose is the U.S. Centrifuge Accommodation
Module. Below it, hidden by the Orbiter, is the U.S. lab module,
flanked by the European (left) and Japanese laboratories.
With the delivery of a second Russian crew transfer vehicle
in June 2002, the station will be virtually complete (the European
Space Agency (ESA) laboratory, known as the Columbus Orbital
Facility, will be joined to the station early in 2003). At that
point, the station will have a full six-person crew capability.
The completed station will measure 361 feet from tip to tip
of the solar arrays. That corresponds to the length of a football
field with both end zones included. However, the area of the
station complex is equal to that of two football fields.
The pressurized living and working space is roughly equivalent
to the passenger cabin volume of two Boeing 747 jetliners. The
atmospheric pressure within the pressurized modules will be 14.7
pounds per square inch, same as on Earth's surface.
There will be seven laboratories. The U.S. is providing two
of them, the basic laboratory module and a special Centrifuge
Accommodation Module. There will be three Russian research modules,
the Japanese JEM and ESA's Columbus module. The U.S., ESA and
Japanese laboratories together provide 33 International Standard
Payload Racks; additional payload capability will be available
in the Russian modules. In addition, the JEM has an exposed "back
porch" with 10 mounting spaces for experiments that require
long duration contact with the space environment; the JEM has
a small robotic arm for moving back porch payloads.
This concept views the station from the opposite (aft port)
end. In the foreground (lower right) is the Russian Service Module,
with living and working room for three crew members. Next, toward
center of photo, is the FGB energy block, then (near the Orbiter)
the U.S. lab module. The vertically-mounted cylinder below it
is the U.S. habitation module.
A central girder connecting the various modules and the main
solar power array is the U.S.-built integrated truss. Moving
along the truss for robotic assembly and maintenance operations
is the Canadian-built Remote Manipulator System with its 55-foot
robot arm and mobile transporter. The four modules of the solar
array, generating a combined 92 kilowatts of power, rotate on
the truss to maximize their exposure to the Sun.
The International Space Station will operate at an average
altitude of 220 miles. At that altitude, minute drag forces will
cause the station to lose height very gradually, so it will be
necessary to reboost it every 90 days. The reboosting will be
accomplished by the FGB.
Beginning with the 1997 launches of the Russian Proton and
the Space Shuttle, there will be 73 assembly and service flights
until the station becomes fully operational in midyear 2002.
The Space Shuttle will make 27 trips, 21 for assembly operations
and six for utilization/outfitting. The Russian Proton and Progress
and Ukrainian Zenit launch vehicles will make 45 flights; 15
of them will be made by the Progress vehicle, bringing up propellant
for the reboost work.
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