Planetary protection treaties and recommendations
In 1967, most of the world’s nations ratified the United Nations Outer Space Treaty.
The treaty’s planetary protection provisions stipulate that nations shall “pursue studies of outer space, including the Moon and other celestial bodies, and conduct exploration of them so as to avoid their harmful contamination and also adverse changes in the environment of the Earth resulting from the introduction of extraterrestrial matter.”
The UN incorporated these provisions in its 1979 Moon Treaty governing the activities of states on the Moon and other celestial bodies, and in the Vienna Declaration of 1999.
Cospar1 translates these provisions into recommendations.
Recommendations are tailored to the type of space mission—from planetary flybys to probe landings—and celestial body explored.
The risk of contamination by terrestrial micro-organisms depends on their ability to survive the voyage and on the conditions they find on arrival.
Cospar classifies missions according to 5 categories. The highest level of precaution (category 5) applies to space missions intending to return extraterrestrial samples to Earth.
Scientists are regularly discovering lifeforms on Earth in the most unexpected places. Biological contamination risks need to be continuously reviewed in the light of new knowledge about celestial bodies and the Solar System.
For this reason, planetary protection recommendations are regularly updated, particularly at Cospar’s Scientific Assembly convened every 2 years.
1Cospar : COmittee on SPAce Research