Rock samples on Mars collected by the Perseverance rover “reveal a potentially habitable sustained environment” existed on the planet, meaning alien life could have too, according to NASA scientists.
Salts spotted within these rocks are suspected to have formed when groundwater flowered through the original minerals of the rocks, or when liquid water evaporated.
NASA hopes that the salt minerals have trapped tiny bubbles of ancient Martian water, which could serve as microscopic time capsules – as salt minerals are known to preserve signs of ancient life on Earth.
The space agency selected the Jezero crater for this mission specifically because it showed signs of being an ancient river delta, and the aim was to drill deep down into the sediment of where this river once flowed to check for the remnants of alien life.
It is certain that a lake once filled the crater, but for how long is unknown. NASA previously said its scientists couldn’t dismiss the possibility that Jezero’s lake was a “flash in the pan” filled with floodwaters that dried up in the space of 50 years.
But the signs from the rock samples suggest groundwater was present for much longer than that.
Although the scientists can’t be certain whether the water that altered these rocks was present for tens of thousands of years or for millions of years, they are growing increasingly certain it was there long enough to welcome microscopic life.
“These samples have high value for future laboratory analysis back on Earth,” said NASA’s Mitch Schulte.
“One day, we may be able to work out the sequence and timing of the environmental conditions that this rock’s minerals represent. This will help answer the big-picture science question of the history and stability of liquid water on Mars.”
The carefully selected samples of Martian rock and soil wouldn’t be completely analysed immediately, as the equipment needed to do that is too complicated to send to Mars.
Instead, the rover will cache the samples in titanium tubes and these will be collected by another rover in approximately a decade’s time.
NASA and the European Space Agency are planning a Mars sample return campaign, where these samples can be examined with instruments that are far too large and complex to send to Mars.
“Detailed maps will be provided for any future mission that might go to Mars and pick up these samples for study by scientists,” NASA said at the time.