Massive Lockheed Martin-built solar arrays to be launched to International Space Station
SUNNYVALE, CA, 27-NOV-00 -- The first of four pairs of massive solar arrays for the International Space Station, built at Lockheed Martin Space Systems in Sunnyvale, will be launched aboard the space shuttle Endeavour to the International Space Station on November 30, 2000. During the 12-day mission, astronauts will connect the package of giant solar arrays and associated electronics, batteries, radiators, and support structure to the Station. Subsequent pairs of arrays will be delivered on shuttle flights currently scheduled for 2002, 2003, and 2006. We're enormously pleased to see the first pair of flight wings headed for the International Space Station, while work continues here on the remaining flight articles, said Ron Paulson, Vice President, Remote Sensing and Space Science, at Space Systems in Sunnyvale. A very thorough series of tests and analysis has demonstrated to us that this complex technology will harness the Sun's energy for the Space Station and provide the power required for many years to come on this vitally important international mission.
The functional testing of the solar array flight hardware has involved several extension and retraction cycles of the 107-foot deployment mast and solar array blankets. Additionally, all individual solar panel circuits have been flash-tested with simulated sunlight to verify output power. Further, a close inspection has ensured that individual solar cells can withstand the harsh environment of space while converting sunlight into electricity. Arrays have also been exposed to harsh vacuum and thermal environments that simulate conditions 200 miles above the Earth's surface, and tested further in an acoustic chamber to simulate the violent shaking vibrations that accompany launch aboard the Space Shuttle. The technology has already been flight proven in a demonstration prototype solar array replacement flown by NASA and Space Systems on the Russian MIR space station.
The Space Systems ISS solar arrays are the largest deployable space structure ever built and will be by far, the most powerful electricity-producing arrays ever put into orbit. When the Station is completed a total of eight flexible, deployable solar array wings will generate the reliable, continuous power for the on-orbit operation of the ISS systems. The eight array wings were designed and built under a $450 million contract from the Boeing-Rocketdyne Division in Canoga Park, Calif., for delivery to the Boeing Company and NASA.
Each of the eight wings consists of a mast assembly and two solar array blankets. Each blanket has 84 panels, of which 82 are populated with solar cells. Each panel contains 200 solar cells. The eight photovoltaic arrays thus accommodate a total of 262,400 solar cells. When fully deployed in space, the active area of the eight wings, each 107 by 38-feet, will encompass an area of 32,528-sq. ft., and will provide power to the ISS for 15 years.
In addition to the arrays, Space Systems in Sunnyvale has also designed and built other elements for the Space Station that will be launched on future shuttle missions. Rotary mechanical joints for the ISS will move the solar arrays and thermal radiators into positions relative to the Sun that will optimize their individual functions. These mechanical joints are the largest mechanisms ever designed to operate in a space environment.
The two Solar Alpha Rotary Joints (SARJ) are each 10.5 ft diameter and 40 inches long. Their purpose is to maintain the solar arrays in an optimal orientation to the Sun while the entire Space Station orbits the Earth once every 90 minutes. Drive motors in each SARJ will move the arrays through 360 degrees of motion at four degrees per minute.
The Thermal Radiator Rotary Joints (TRRJ) are each five and a half feet long and three feet in diameter. Their purpose is to maintain the Space Station thermal radiators in an edge-on orientation to the sun that maximizes the dissipation of heat from the radiators.
Space Systems has also produced the Trace Contaminant Control System, an advanced air processing and filtering system that will ensure that over 200 various trace chemical contaminants, generated from material off-gassing and metabolic functions in the Space Station atmosphere, remain within allowable concentration levels. It will become an integral part of the Space Station's Cabin Air Revitalization Subsystem.
Lockheed Martin Space Systems in Sunnyvale, CA, is a leading supplier of satellites and space systems to military, civil government and commercial communications organizations around the world. These spacecraft and systems have enhanced military and commercial communications; provided new and timely remote-sensing information; and furnished new data for thousands of scientists studying our planet and the universe.