Policy Documents

Coalition for Deep Space Exploration

September 4, 2020



On July 9, 2020, NASA Administrator Jim Bridenstine announced updates to planetary protection policies for future missions to the Moon and Mars. The update comes as NASA plans for a sustained human presence on the Moon, future crewed missions to Mars, and substantial involvement of the private sector in the space agency’s missions. The policies are applicable to missions that involve NASA either entirely or partially.

Planetary protection is the practice of avoiding contamination of bodies outside Earth by Earth biology, referred to as forward contamination, and to protecting the Earth from life forms that may come back from other worlds, or backward contamination. The concept of planetary protection is codified in Article IX of the Outer Space Treaty (OST) of 1967, which stipulates that states must avoid contamination of the Moon and other bodies when conducting exploration, and avoid the contamination of Earth by extraterrestrial matter. The article also mandates that states adopt planetary protection measures where appropriate. NASA’s planetary protection policies are grounded in this stipulation.

One of the two new policies released by the space agency is the NASA Interim Directive (NID) 8715.128, which offers guidance for robotic and crewed missions to the Moon and allocates lunar regions in two different categories according to the level of protection necessary. Under category I-L are the regions not considered of direct interest for understanding the process of chemical evolution, and areas where terrestrial contamination will not jeopardize exploration. Under category II-L are lunar zones where there is a possibility that biological contamination could compromise research. Under this last category are permanently shadowed regions of the Moon that have value in the study of the solar system’s history, as well as potential value for In-Situ Resource Utilization (ISRU). Also in category II-L are Apollo landing and other historic sites, which have worth specifically for studying materials left by the Apollo astronauts. Missions to category II-L areas are required to report biological materials.

NASA Interim Directive 8715.129 does not offer specific guidance but lays down activities that NASA will conduct to support planetary protection in future human missions to Mars. According to the Directive, with the goal of ensuring that the search for life on Mars can be conducted in a verifiable manner, NASA will take actions such as developing technologies for mitigating contamination release or intrusion on Mars, and determining whether it would be necessary to conduct an in-situ experiment at a location where humans would land on a mission to the Red Planet. In contrast with the Moon Directive, the Mars Directive covers both forward contamination as well as backward contamination of the Earth-Moon system associated with human missions that land, orbit, flyby, and return from Mars. Backward contamination of Earth from Moon samples has been unrestricted since the end of Apollo 14 in 1971.

Due to the changing nature of planetary protection policies, both NIDs are works in progress and remain open to change when new information arises from continued research in low Earth orbit and investigations conducted through activities such as the Artemis program.



For further information on this topic or other Coalition for Deep Space Exploration policy briefs, please contact: Jamil Castillo – Manager, Space Policy Coalition for Deep Space Exploration


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