ment of the Earth (Article IX of the Treaty). The Outer Space Treaty has no termination date and is open to signature by any state with an interest in its objectives. Any state party to the treaty can propose amendments to it, which must be accepted by a majority of the states—unlike the Antarctic Treaty, which requires consensus for every decision. Again unlike the Antarctic Treaty, there is no distinction in the types of parties or member states involved in the Outer Space Treaty, regardless of whether they are actively involved in space exploration and/or launched missions.1

In addition to being centered on a treaty for its framework, planetary protection is interpreted and applied through designated international scientific bodies. In the final analysis, the application of planetary protection is like the Antarctic Treaty in that implementation depends on a political and legal forum in which science plays an advisory role—and the “launching state” is responsible for compliance. Historically, the technical aspects of planetary protection are developed through deliberations by COSPAR, which is part of the International Council for Science (ICSU) and is consultative to the United Nations in this area.

In recent years, planetary protection policy for solar system exploration missions has been developed by the member nations of COSPAR through its Panel on Planetary Protection (PPP). The PPP is responsible for developing, maintaining, and promulgating PP knowledge, policy, and plans to avoid harmful biological contamination of other worlds by terrestrial organisms and to avoid the potential contamination of Earth by returned extraterrestrial materials. (NASA 1999; COSPAR 2002; Rummel 2006). The COSPAR PPP accomplishes its work through symposia, workshops, topical meetings, and business meetings at the COSPAR Scientific Assembly held every two years. In this way, the PPP is able to act as an international forum for the discussion and exchange of information related to planetary protection (PP), and to deliberate over implementation concerns or needed revisions in policies based on updated scientific information. Recommendations and decisions arising from PPP meetings are submitted to the COSPAR Bureau for official consideration, with final approval subsequently subject to decisions by the COSPAR Council before they may take effect.

In the United States, NASA oversees the application of procedures and guidelines under a policy directive (NASA 1999) aimed at ensuring compliance with COSPAR planetary protection policy. NASA also undertakes regular interaction with the scientific community and may request recommendations on specific issues from the Space Studies Board (SSB) of the U.S. National Research Council (NRC). The NRC is an operating arm of the U.S. National Academies and is the U.S. member institution and adhering body to COSPAR. Due to the accelerating pace of solar system exploration, NASA’s Advisory Council (NAC) also chartered a Planetary Protection Advisory Committee in 2002, (now a NAC subcommittee) for internal advice on planetary protection matters. Table 5.1 provides a direct comparison of key governance and policy features for exploration of both the solar system and Antarctica. Table 5.2 discusses review processes for individual research proposals.

The current COSPAR and NASA PP policy uses a classification system for individual projects based on four categories (I-IV), each of which is determined by a combination of both the intended target body and the type of mission and activities planned.


A country can be involved in exploration either by launching its own missions or by a research partnership on another country’s mission. The country launching the mission must comply with the PP regulations and ensure that its research partners are in compliance.

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