Surviving the Space Junkyard:Using a Hypervelocity Ballistic Range to Assess Orbital Debris Impacts

摘要

Space junk is a growing concern. According to NASA, there are over 19,000 pieces of man-made junk larger than 4 inches (10 cm) orbiting the Earth. This doesn't include the hundreds-of-thousands of pieces too small to be tracked, but still large enough to pose a threat to operational satellites or generate additional debris through impact with other space junk. A typical risk reduction plan for spacecraft involves using shields to stop small objects (<1 cm in diameter) and avoidance for large objects (>10 cm). Shields provide good protection, but must be designed for a particular hazard (ie, Whipple bumpers can withstand 1 cm spheres up to 7 km/s). However, performance of these shields, and ultimately the outcome of an unfortunate hypervelocity impact, is a function of spacecraft and debris material, mass, size, shape and velocity. Even though orbital velocities can reach 16 km/s, current debris models have not been validated at these higher velocities. Two-stage light gas guns are used as the primary source of hypervelocity impact data. The hypervelocity ballistic Range G at the Arnold Engineering Development Center (AEDC) is the world's largest operating two-stage light gas gun and has proven performance unsurpassed by others of its type. A wide range of unique test techniques, capabilities and instrumentation make Range G ideal for research and development of spacecraft required to address the ever growing problem of orbital debris. This paper describes Range G and how its unique capabilities and versatility can be used to address orbital debris issues.