NASA Discovery Could Explain Why We've Never Found Life on Mars

Why is Mars barren and uninhabitable, while life has always thrived here on our relatively similar planet Earth?

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A discovery made by a NASA rover has offered a clue for this mystery, new research said Wednesday, suggesting that while rivers once sporadically flowed on Mars, it was doomed to mostly be a desert planet.

Mars is thought to currently have all the necessary ingredients for life except for perhaps the most important one: liquid water.

However the red surface is carved out by ancient rivers and lakes, showing that water once flowed on our nearest neighbour.

There are currently several rovers searching Mars for signs of life that could have existed back in those more habitable times, millions of years ago.

Earlier this year, NASA's Curiosity rover discovered a missing piece in this puzzle: rocks that are rich in carbonate minerals.

These "carbonates" such as limestone on Earth - act as a sponge for carbon dioxide, pulling it in from the atmosphere and trapping it in rock.