Spotted Martian rocks hint at microbial life

Dark-rimmed ‘leopard spots’ in a rock studied by NASA’s Perseverance rover last year could be the remains of microbial activity on Mars. The rings aren’t a sure sign that microbes once thrived on the Red Planet; the only way to know for certain is to analyse a sample of the leopard-spotted rock here on Earth. Perseverance has a sample awaiting a ride off Mars for precisely that purpose. For now, the rings are being treated as ‘an intriguing signal’ of ancient Martian life, but far from a sure thing, said researchers at a conference yesterday.