Flag of USA
National Aeronautics and Space Administration (NASA)
  NASA has performed orbital debris risk assessments since the Gemini program in the 1960's and has conducted a formal, comprehensive orbital debris research program in support of human space flight and robotic missions since 1979. This effort is led by the Orbital Debris Program Office at the NASA Lyndon B. Johnson Space Center (JSC) and encompasses the full spectrum of orbital debris issues, including
  • the definition of the present orbital debris population and debris sources;
  • the modeling of the current and future orbital debris environment;
  • the protection of satellites by shielding and operational procedures; and
  • the curtailment of the growth of orbital debris through mitigation policies and procedures, including satellite design and operation considerations.
Measurement of near-Earth orbital debris is accomplished discretely and statistically with a wide assortment of ground-based radars and telescopes, in situ experiments, and the examination of returned spacecraft surfaces. In addition to utilizing the official U.S. Satellite Catalog of objects normally greater than 30 cm in diameter, NASA employs the Haystack, Haystack Auxiliary, Goldstone, Cobra Dane, and ALTAIR radars to collect information on the small debris environment (0.3 - 30 cm). Uncataloged debris greater than 30 cm in diameter near the geostationary orbit are the target of Michigan Orbital Debris Survey Telescope (MODEST). The environment definition for very small particles (<1 mm) is aided by inspections of exposed spacecraft surfaces, such as the Space Shuttle, the International Space Station, and the Hubble Space Telescope.

NASA's two principal models of the near-Earth particulate environment are ORDEM and LEGEND. The former is an engineering model designed to facilitate orbital debris risk assessments in the near-term, while the latter is a long-term satellite evolutionary model used to examine the effects of orbital debris mitigation policies on the future satellite population. Other models, like the Satellite Breakup Risk Assessment Model (SBRAM), have been developed to support real-time satellite operations or general orbital debris research.

Hypervelocity impact phenomenology research, by testing and complex computer codes, enables NASA to assess the vulnerability of space components to orbital debris and meteoroid impacts and to develop new, more efficient, more robust debris shield designs. This work has led directly to safety improvements for the Space Shuttle and the International Space Station. The Hypervelocity Impact Technology Facility (HIT-F) coordinates this activity at JSC.

NASA developed the first comprehensive collection of orbital debris mitigation guidelines which are now reflected in NASA Standard 8719.14. Using these guidelines as a foundation, in 1997 the U.S. Government established a set of orbital debris mitigation standard practices for use by both government and commercial launch vehicles and spacecraft. The concepts of many of these standard practices have found their way into the growing number of orbital debris mitigation guidelines around the world.

The NASA Orbital Debris Program Office at JSC directly supports all NASA satellite programs, other U.S. Government agencies, the U.S. aerospace industry, many other national space agencies, and discussions of orbital debris at the United Nations, as well as the many activities of the IADC. Additional information can be found at