Aliens could be living inside ice on Mars.
Researchers believe that there is a thick enough layer of ice on the Red Planet to protect a living organism from the extreme ultraviolet radiation that is thought to make it impossible for life to survive on the surface.
After boffins tested if it would be possible to exist, given the dust and form of ice found on Mars, they ruled that if the layer did not contain too much dust – between 0.01-0.1 per cent - there may be a region that would sustain life between five and 38cm.
It was also found that if the ice was cleaner, the habitable zone would be bigger at a depth of between 2.15 and 3.10m.
The dust within the ice would occasionally melt the layer, resulting in enough water to help photosynthesis, which is required for living organisms to survive.
Dr. Aditya Khuller, who led the study for NASA, said: "If we're trying to find life anywhere in the universe today, Martian ice exposures are probably one of the most accessible places we should be looking."