AEROSPACE

Vital Data on Space Debris Safeguards U.S. Satellites and Spacecraft -- With thousands of tons of space debris orbiting the Earth, the important task of monitoring the whereabouts of operating and now-defunct spacecraft rests with the Air Force Space Command's 1st Space Control Squadron (1SPCS), Cheyenne Mountain Air Force Station, Colo. To help compile and analyze more than 300,000 daily observations and to maintain a database of more than 10,000 Earth-orbiting space objects, 1SPCS relies on SGI high-performance computing and storage technology to ensure the right information gets into the hands of decision makers at the right time. 1SPCS is the focal point for U.S. military and civilian organizations, such as United States Strategic Command and NASA, that need vital, up-to-the-minute information on space debris, which can be anything from fragments of an exploded rocket to an entire derelict spacecraft. 1SPCS commands and controls the worldwide Space Surveillance Network of operational sensors designed to detect, track, identify and catalog positional data for all man-made objects in the Earth's orbit. This data is forwarded to 1SPCS for compilation and analysis on SGI high-performance computing and storage systems. "As part of the Space Surveillance Network Improvement Program, SGI server technology has been purchased to help us better track and identify different types of man-made space objects and provide this data to our customers in near-real time," said Air Force Lt. Col. Scott F. Shepherd, commander, 1SPCS. "SGI Origin 3000 servers are robust storage management systems for managing very large mission-critical data repositories, such as those operated in support of the Space Surveillance Network." 1SPCS maintains an SGI high-speed Fibre Channel storage area network combined with SGI(R) CXFS(TM) -- the highest performance shared filesystem in the industry -- which enables groups of computers to simultaneously access large amounts of data, providing a single filesystem view of the current computerized catalog of all orbiting man-made objects. Based on this shared data, 1SPCS charts preset positions, plots future orbital paths, and forecasts where and when objects might re-enter the Earth's atmosphere. Since the launch of Sputnik in 1957, over 26,000 man-made objects ranging from debris the size of a baseball to the Mir Space Station have been catalogued, many of which have since re-entered the atmosphere. This information is analyzed by 1SPCS to determine potential impacts on U.S. and allied space assets so that timely warnings and recommendations for suitable countermeasures can be made. Information on objects moving out of stable orbit that are ready to re-enter the Earth's atmosphere is forwarded by 1SPCS to U.S. Space Command 14 days before an object is projected to re-enter the atmosphere. One important protection mission the 1SPCS conducts on a regular basis is collision avoidance analysis for the space shuttle and the International Space Station. 1SPCS constructs a theoretical box around a high-priority object, such as the space shuttle, and projects the flight path for 36 to 72 hours. If any of the 10,000-plus catalogued objects intersects this theoretical box, 1SPCS will forward the analysis to NASA, which will determine whether to change the flight path of the shuttle. Since the inception of this mission in 1981, NASA has moved the space shuttle 12 times and the International Space Station five times based on analysis from 1SPCS.