by Johnson Space Center

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The "terrible twos" aren't so terrible for the International Space Station.

The world's first international orbital outpost celebrates the second anniversary of continuous residency and permanent human presence in space Saturday, Nov. 2. The anniversary marks an ambitious and virtually flawless year of expansion and research in space.

Already the largest, most sophisticated and powerful spacecraft ever built, when its second year of occupancy began in 2001, the station has grown by more than 56,000 pounds in components added during the past 12 months. Over the last two years, the station has grown by more than 200,000 pounds, and its internal volume has increased from that of an efficiency apartment to a three-bedroom house. This year, construction began on the station's backbone, a truss structure that eventually will support almost an acre of solar panels to provide more power for orbital research than ever before.

"The International Space Station was truly spectacular a year ago, but with each new assembly mission -- almost one every month -- it's further enhanced," said Bill Gerstenmaier, International Space Station Program Manager, NASA Johnson Space Center, Houston. "Our success in the past two years has been phenomenal. We are blazing a trail in space and on Earth, through research and international cooperation, which can improve lives and expand exploration. We have many challenges ahead, but this team's continued hard work and dedication will build a final facility that eclipses even today's station," he said.

By the end of 2002, the station's truss will stretch almost 133 feet. When completed in 2004, the truss will stretch 356 feet; longer than a football field. This year has seen assembly of the first "space railroad," including a mobile base on the truss for the station's Canadian robotic arm and a "hand car" for spacewalkers.

As the station expands, so does its research capability. Experiments aboard the complex have attained more than 90,000 hours of operating time. Sixty-five U.S. investigations have been launched as well as numerous international studies.

An example of Station-based research recently involved the first-ever soybean crop grown in space. After spending nearly 100 days aboard the Station and returning on a visiting Space Shuttle, the seeds are undergoing several months of chemical and biological tests on Earth to reveal whether their growth in a low-gravity environment changed their chemical composition.

Soybeans are a leading source of protein in the human diet and are used in many products, from oil to crayons. Space Station research, in conjunction with commercial companies, in this area could lead to producing crops that support long-term human presence in space and possibly pave the way for improving crops grown on Earth.

In the past 12 months, 33 people have visited or lived aboard the orbiting complex. A total of 112 visitors have been aboard the station since it was launched, including men and women from six nations. The first crewmembers docked with the Station to begin its permanent occupancy on November 2, 2000. Five three-person crews have lived aboard for durations ranging from four to more than six months. In its second year of occupancy, astronauts and cosmonauts have conducted 16 spacewalks for maintenance and assembly of the Station.

More information about the Station is available on the Internet at: