In response to NASA’s request for an interim report, the committee proposes the following working definition of planetary protection that remains consistent with U.S. obligations under the Outer Space Treaty, recognizes the challenges of future space missions, and is consistent with current planetary protection approaches as enunciated by the Committee on Space Research (COSPAR) and adopted by NASA:
Planetary protection involves at least three fundamental activities—policy formulation, policy implementation, and compliance and validation. It encompasses those goals, rationales, policies, processes, and substantive requirements that are intended to ensure that any interplanetary space mission does not compromise the target body for a current or future scientific investigation and does not pose an unacceptable risk to Earth (in the case, for example, of sample return missions).
In addition, the following additional statement may be added in the final report, depending on the resolution of deliberations on the third rationale:
Further, in the course of ensuring the biological safety of the Earth and other bodies, planetary protection has a role in safeguarding the scientific objectives of future investigations, specifically investigations aimed at ascertaining the possible occurrence and nature of life on other solar system bodies.
This working definition reflects the committee’s examination of the issues to date and is, of necessity, incomplete. As such it should be regarded as a work in progress. For example, the definition specifically does not address the important issue of roles and responsibilities in the planning, design, and execution of space exploration missions. However, this definition does make it clear that planetary protection involves the disciplines of science (astrobiology, microbiology, etc.), mission design (trajectory biasing, etc.), engineering (including engineering practice), management (particularly establishing policy and requirements), cost and risk assessment, and biological containment, among others. The working definition also encompasses a scientific mission assurance function—a responsibility to promote the likelihood of achieving mission success and the furtherance of solar system exploration. To quote a recent COSPAR document, “protection policies should enable the exploration of the solar system, not prohibit it.”1
1 COSPAR Panel on Planetary Protection, “Proposed New Terms of Reference for the COSPAR Panel on Planetary Protection,” COSPAR, Paris, France, 2017, p. 1. Approved by COSPAR Bureau on March 22, 2017.