The Defense Department has a goal of eliminating exemptions to the federal government’s orbital debris mitigation standard practices by 2018, according to a key official.
Office of the Secretary of Defense (OSD) Space Policy Adviser Josef Koller said Nov. 18 his office has received about eight exemption requests since 2010, when the National Space Policy (NSP) elevated approvals for orbital debris mitigation guidelines exemptions to OSD from levels like Air Force Space and Missile Systems Center (AFSMC) and the National Reconnaissance Office (NRO).
Koller said NASA in 1995 issued a comprehensive set of guidelines that became the foundation for the United States’ overall efforts to reduce the amount of space debris. Experts have warned for decades the risks that increasing amounts of space debris bring to not only U.S. government satellites but also commercial satellites. Space debris can be classified as anything ranging from defunct satellites to discarded rocket stages and even a 1 cm object.
Agencies, Koller said, are also required to notify the State Department when requesting exemptions to the orbital debris mitigation guidelines. According to his LinkedIn bio, Koller became space policy adviser in May.
“We don’t want to give out exemptions left and right,” Koller said at the University of Maryland’s Center for Orbital Debris Education and Research (CODER) workshop in College Park, Md.
Koller said only U.S. government agencies are required to follow these guidelines, though he didn’t specify if they were legally-binding. Commercial industry, he said, is encouraged to follow the guidelines.
There are four main objectives to the government’s standard practices for orbital debris mitigation. The first is to control debris released during normal operations. Spacecraft and upper stages should be designed to eliminate or minimize debris released during normal operations. Each instance of planned debris release larger than 5 mm in any dimension that remains on orbit for more than 25 years should be evaluated and justified on the basis of cost-effectiveness and mission requirements.
The second objective is to minimize debris generated by accidental explosions both during and following mission operations. This can be accomplished by depleting or safely storing on-board sources of stored energy when they are no longer required for mission operations or post-mission disposal. Programs should also demonstrate in the design of a spacecraft or upper stage that no credible “failure mode” for accidental explosion exists, or if it does, it should design procedures that will limit the probability of their occurrence.
The third objective is the selection of a safe flight profile and operational configuration. In developing the design and mission profile of a spacecraft or upper stage, a program estimates and limits the probability of collision with known objects during orbital lifetime.
The fourth objective is the post-mission disposal of space structures. A spacecraft or upper stage may be disposed of by one of three methods: atmospheric reentry, maneuvering to a storage orbit or direct retrieval. There are four storage orbits: between low earth orbit (LEO and medium earth orbit (MEO), between MEO and geosynchronous earth orbit (GEO), above GEO and heliocentric orbit, where the structure is removed from earth’s orbit.
DoD has various ways of encouraging compliance with the guidelines, Koller said, including writing the guidelines into contracts. Koller said when the Air Force, DoD’s launch provider, buys a new launch capability, the guidelines are written into the contract. He didn’t specify which guidelines, or if all of them, were included in all Air Force contracts.
The FAA, the National Oceanic and Atmospheric Administration (NOAA) and the FCC also consider orbital debris issues as factors in the licensing process for spacecraft and upper stage rocket engines under their auspices, according to a January report from the Congressional Research Service (CRS) obtained by the Federation of American Scientists (FAS).