International Space Station (ISS) Information

Space Station Activities

Welcome to the International Space Station Update and Visibility page

Space Shuttle Atlantis (STS-110) successfully launched on April 8 to install the anchor section of what will become a huge cross truss that ultimately will support the station's four sets of solar arrays. The truss, called "S0" (pronounced S-zero) is the first of nine truss elements that will be bolted together over the next two years to form the structural backbone of the station. Four huge sets of solar arrays eventually will be attached to the truss, two at each end, providing the power needed to operate the completed station's research gear and life support systems.

S0 will anchor the entire truss, attaching directly to the top of the U.S. Destiny laboratory module. Power lines from the outboard solar arrays will feed through S0 into the station, as will ammonia coolant lines leading to and from the outboard radiators that will keep the station's electrical systems from overheating. S0 is equipped with four computers, two laser ring gyros and GPS antennas for on-board navigation, 664 feet of ammonia coolant lines, 10 miles of electrical cabling, 971 electrical connectors and complex power control and conditioning equipment.

The 44-foot-long S0 truss also is equipped with a TRW-built rail car that will roll along tracks running the length of the completed truss, carrying the station's Canadarm 2 robotic crane to various work sites as required to install new equipment or to help spacewalking astronauts make repairs. "Once we add the mobile berthing system to the mobile transporter on the next flight (in early June), it will allow the robotic arm to travel the length of the truss," said space station flight director Robert Castle. "So we can actually grapple things, roll along the length of the truss and install things at the end of it."

In fact, the solar array wings - all two acres of them - and other critical outboard power and cooling systems cannot be installed without using the Canadarm2 on its mobile platform. And the first step on the road to completing the station's initial assembly is installation of the S0 truss.

Space shuttle Endeavour (STS-108) successfully flew December 5-17 to ferry a new resident crew and supplies to the ISS. The mission delivered the Expedition Four crew of commander Yuri Onufrienko and flight engineers Carl Walz and Dan Bursch to the orbiting space station for a five-month stay and return to Earth the Expedition Three crew of Frank Culbertson, pilot Vladimir Dezhurov and flight engineer Mikhail Tyurin who have been aloft since August.

This sixth and final shuttle mission of 2001 caps a record-breaking year of missions that completed the first phase of the station's orbital construction.

While NASA faces a shuttle flight reduction in 2003 and other measures to bring space station costs in line with budget projections, 2002 promises to be just as ambitious as the last.

In 2001, NASA and the Russian Space Agency put up about 45 tons of new equipment and modules, bringing the total mass to around 184 tons. That figure could double in 2002 as NASA begins to add more truss segments to the station.

Since the continuous human presence stage began in November of 2000, there has been a total of 16 visiting vehicles to the ISS. That's eight shuttle flights, five Russian Progress flights, two Soyuzes and the docking compartment. In that same time there were 18 spacewalks to assemble and maintain the station. (In 2002 there are a projected 20 spacewalks.) Over the past year there were about 50,000 hours of experiment operating time, which includes both the crew-tended experiments as well as the remote telescience operations.

The International Space Station is the most ambitious engineering project in world history. The program involves 16 partner countries, including the U.S., Russia, Japan, the 11 members of the European Space Agency, and Brazil, who have joined together to build the most capable space laboratory ever constructed. When complete in 2006, the International Space Station will be about the size of a three-bedroom house and will be home to up to seven astronauts at a time, who will work on experiments running the gamut of scientific disciplines.

Access to mission commentary will be through the human space flight website at

ISS Visibility Information

See the ISS in the Skies Over Your Home Town!

The International Space Station is already large enough to show up as a moving dot as bright as Jupiter in the nighttime sky. To see tables showing the times and positions of ISS flyovers at your location, click on the "Heavens-Above" website listed below. The site easily allows you to plug in your own location (either by city or entering latitude and longitude). You can then get a display of the ISS' visibility for the next 10 days, as well as sky charts showing where to find it relative to the stars. Go to: When you first access the site, set up your geographical location, bookmark it, and it will keep that information for future logins.

Contact Information

Mail: Angela Des Jardins E-mail: E-mail Angela
Montana Space Grant Consortium Phone: (406) 994-6172
4176 Cobleigh Hall, Montana State University FAX: (406) 994-4452
Bozeman, MT 59717    

Montana Space Grant Home

Updated December 9, 2002