National Aeronautics and Space Administration Planetary Protection Office

Compliance with planetary protection requirements is mandatory for NASA missions, as per NASA Policy Directive (NPD) 8020.7G: Biological Contamination Control for Outbound and Inbound Planetary Spacecraft. The first and most important step in complying with NASA planetary protection policy is avoiding unintended encounters with solar system objects. As described in NPR 8020.12D: Planetary Protection Provisions for Robotic Extraterrestrial Missions, missions must meet a certain set of forward contamination criteria including:

Careful mission design and planning are essential elements when considering planetary protection requirements, which are both mission and target body dependent. Consultations with the Planetary Protection Officer (PPO) during mission development is critical in ensuring compliance with NASA policy. Provided below are examples of how consultation with the PPO leads to mission-specific implementation of NASA policy.


Mars 2020
As presented in the December 2015 Planetary Protection Subcommittee meeting, and pending final approval, the Mars 2020 project will be designated a Category V Restricted Earth Return mission, while the outbound leg will be required to comply to Category IVb constraints at the sub-system level. Accordingly, certain clarifications to NPR 8020.12D will apply to Mars 2020 (M2020). Examples clarifications include:

Sections 5.3.2.3c & 5.3.2.5c

Sections 5.3.2.5a

Secton 5.3.2.2

Section 5.3.3.2