Nasa scientists may still be celebrating their discovery of liquid water on Mars, but they now face some serious questions about how they can investigate further and look for signs of life on the red planet.
The problem is how to find life without contaminating the planet with bugs from Earth.
But the rover is not sterile and risks contaminating the wet areas with earthly bugs that will have hitched a ride to the planet and may still be alive.
The vehicle has been trundling around the large Gale crater looking for evidence that Mars was habitable in the ancient past. It has so far uncovered evidence of past river networks and age-old lakes.
However, the dark, damp streaks, called recurring slope lineae (RSL), are a different prospect. Because they are wet at least part of the time, they will be designated as special regions where only sterile landers can visit. But such a restriction could hamper scientists’ hopes of looking for current life on Mars.
“There will be heated discussions in the next weeks and months about what Curiosity will be allowed to do and whether it can go anywhere near the RSLs,” said Andrew Coates of University College London’s Mullard space science laboratory.
“Curiosity now has the chance, for example, to do some closer up, but still remote, measurements, using the ChemCam instrument with lasers, to look at composition. I understand there is increasing pressure from the science side to allow that, given this new discovery.”