I understand NASA and other space agencies have rules in place to protect planets or moons that might harbor life. This includes requirements to sterilize spacecraft as well as avoid impacts.

There is a small chance the Tesla Roadster will eventually collide with one of the affected planets or moons.

What rules regarding planetary protection applied to this launch? What did SpaceX do to satisfy them?


1 Answer 1


Nothing. The trajectory is such that it won't intersect any planet for a very long time. The sterilization requirements only apply if it is expected to hit an object within a short period of time. The actual requirement can be found here.

Category III missions to Mars (flybys and orbiters), as well as cruise stages, as stated in Section of NPR 8020.12D, shall avoid Mars impact at a probability no less than 0.99 for 20 years after launch and a probability no less than 0.95 for the period 20-50 years after launch.

  • $\begingroup$ Thanks! 50 years is much shorter than I would have thought, and I don't see any longer timeframes on the requirements you linked. Do you know if there are any rules beyond 50 years? $\endgroup$
    – user3087
    Commented Feb 23, 2018 at 19:37
  • $\begingroup$ Not that I can find. $\endgroup$
    – PearsonArtPhoto
    Commented Feb 23, 2018 at 19:43
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    $\begingroup$ The 50 years number has a funny history. It was originally intended to be 50 years from the 1967 Space Treaty, since we will certainly have humans on Mars by 2017, at which point we must have given up on protecting Mars from contamination. As we continued to make no progress on plans to send humans to Mars, the 50 years became a sliding requirement, suggesting that at any point in time, we will certainly have humans on Mars 50 years from now. (Despite the evidence.) $\endgroup$
    – Mark Adler
    Commented Feb 23, 2018 at 23:25
  • 1
    $\begingroup$ @MarkAdler Does something similar apply to Europa and other interesting bodies in the outer solar system? $\endgroup$
    – PearsonArtPhoto
    Commented Feb 23, 2018 at 23:41
  • 2
    $\begingroup$ All protected targets use 50 years after arrival. "The period of biological exploration shall extend at least 50 years after a PP Category III or IV mission arrives at its protected target and no longer than the time point after which no organisms remain viable on the spacecraft." $\endgroup$
    – Mark Adler
    Commented Feb 24, 2018 at 11:17

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