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Is this Opportunity’s last stand? NASA’s long-lived rover is the likes of which no rover has ever seen. The aptly-named Perseverance Valley, where Opportunity is currently hunkered down, is cloaked in enough dust to blot out the sky and make daytime as dark as night.

Less than 0.01 per cent of the sunlight at Mars is currently reaching the rover’s solar panels. Because the rover is entirely run on solar power, its operators have put it into minimal operations mode – its only goal, more important even than sending any signals back to Earth, is to stay warm enough to keep its batteries from being ruined by the cold. Opportunity’s twin rover, Spirit, is thought to have succumbed to the extreme cold of Martian winter in 2010 after it got stuck in soft soil.

NASA says the rover’s most recent transmission, received yesterday, showed its temperature was -29°C. This isn’t the first storm Opportunity has weathered, and the transmission was a good sign, but it’s the most intense dust storm that any rover has experienced on Mars to date.

Deadly dust

The storm spans more than 18 million square kilometres, which is about 12 per cent of the Mars’s surface area – larger than North America. It is not yet clear how long the tempest will last, but dust storms on Mars often go on for weeks or even months.

The Opportunity and Spirit rovers were designed to last for 90 days on the Martian surface. Spirit lasted over 20 times longer than that, and Opportunity is in its 15th year now. It has proven tougher than we thought, and it may yet persevere.