According to the 1967 Outer Space Treaty, no one is allowed to approach any potential water source on another planet, in case of contamination.
As Akshat Rathi explains on Quartz, the treaty “forbids anyone from sending a mission, robot or human, close to a water source in the fear of contaminating it with life from Earth”.
Terrestrial life has shown to be extremely resilient in space, so any spacecraft from Earth could carry potentially harmful microbes to alien worlds.
There are strict rules in place concerning where space agencies are allowed to land on Mars, with certain ‘Special Regions’ designated out of bounds. These include regions that are potentially suitable for supporting Martian life.
NASA already has its Curiosity rover on the surface of Mars, only around 50km from the geographical features where evidence of water has been found. However, even if it was able to reach the site, it wouldn’t be allowed to due to potential contamination.
NASA Mars Program Office’s Chief Scientist, Rich Zurek, explained:
“These features are on steep slopes, so our present rovers would not be able to climb up to them. Because liquid water appears to be present, these regions are considered special regions where we have to take extra precautions to prevent contamination by earth life. Our current rovers have not been sterilized to the degree needed to go to an area where liquid water may be present”.
With NASA planning manned missions to Mars in the 2030s, it will need to come up with ways of sterilizing its equipment to a high degree or risk breaking the rules of the treaty.This is certainly food for thought. Of course we must behave responsibly and avoid contaminating other planets. I hope we do a better job than we have done on our own planet.