alternative on existing data acquisition programs (for example, JSpOC Mission System, Space Surveillance Network (SSN) sensors, other users, etc.).

3. Outline options for a strategy of how AFSPC should proceed with using these alternate standards to meet JSpOC and user requirements. The committee’s examination and description of the options should include the following:

a. Near and far term options,

b. A description of each option’s pros and cons,

c. Avenues towards meeting the unique needs identified,

d. If warranted, transition approaches or potential difficulties with transitioning should also be described.

4. Examine broader issues concerning overall cost and risk of the options. In its report, the committee should consider detailing these issues for several of the larger users of the standards (such as SSN sensors).

5. Prepare a report with recommendations regarding the optimal strategy to utilize the assessed options.

In response, the Committee for the Assessment of the U.S. Air Force’s Astrodynamic Standards collected data and heard from numerous people involved in developing and maintaining the current astrodynamics standards for AFSPC, as well as representatives of the user community such as NASA and commercial satellite owners and operators. As the Cosmos/Iridium incident demonstrates, collisions between objects not owned or operated by the U.S. government can have a profound impact on all of the organizations and countries that operate satellites, including impacts on vital U.S. national security assets. Preventing collisions of space objects, regardless of their ownership, is in the national security interests of the United States.

During the course of its deliberations, the committee was encouraged by the study sponsor to look beyond the narrow issue of the currently used algorithms and consider the broader policy issues associated with their development and evolution. Although the committee was tasked with comparing the existing algorithms with other potentially available algorithms, it was unable to do so because the other algorithms are proprietary and will likely be part of future contract competitions as the Air Force modernizes its systems. Accordingly, and because this study’s sponsor encouraged the committee to consider broader issues, the committee sought to address the overall management environment, of which the algorithms are but one aspect.

The use of the term “standard” in the larger term “AFSPC astrodynamics standard” is different from what one might expect. In the usual sense, “standards” are widely accepted specifications to be used for a specific purpose (e.g., IEEE standards for electrical outlets). Standards are normally expressed only in technical documents. AFSPC astrodynamics standards, however, are physical models and astrodynamics algorithms expressed as computer code. Perhaps a more descriptive name would be “standardized astrodynamics algorithms”—the term that is used throughout the rest of this report to describe AFSPC astrodynamics standards.

The committee concluded that AFSPC’s current system for maintaining and developing the standardized astrodynamics algorithms has done an adequate job, but community needs and changes in national space policy are leading to increased demands. The number of objects in space and the number of operators are increasing and so too is the challenge of maintaining accurate ephemerides of these objects, as well as the difficulty of communicating information about the objects.

Accurate ephemerides on all trackable space objects are maintained at the U.S. Strategic Command (USSTRATCOM) Joint Space Operations Center (JSpOC), which it is AFSPC’s responsibility to organize, train personnel for, and equip with computer and communications systems as the major command (MAJCOM) for space. The JSpOC Mission System (JMS) is the Air Force’s current program to modernize the infrastructure used in the JSpOC for maintaining a catalog of objects in space, tasking sensors, assisting decision makers, and informing satellite owners and operators. JMS is being implemented in a series of steps or phases, with the initial phase emphasizing the use of commercially available software mixed with a judicious use of legacy software as needed.

The committee believes that the primary limitation in the current system for objects not experiencing significant drag is not the accuracy of the algorithms, but rather the quantity and the quality of the sensor tracking data. The key system limitations are current sensor coverage, understanding of the quality of the observations, and the challenge of fusing disparate data from different systems and phenomenology. Understanding the quality or statistics of the observations is necessary for obtaining a realistic covariance, which is needed for computing an



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