When it arrived on the surface of Mars in 2005, NASA only expected the Opportunity rover to last just 90 days, but 12 years on, it is still going strong on our closest planetary neighbor.

It was initially believed that harsh dust would kill the vehicle within just three months and while it only now operates at a snail’s pace, it is still cruising across Mars.

Thus, it holds the record for the longest distance traveled on another planet, having covered around 27 miles in 12 years.

The rover is solar-powered, the size of a golf cart and operated by scientists through complex codes which take 20 minutes to arrive on Mars.

In its first year of operation on Mars, Opportunity came close to fail after getting stuck in a sand dune. It took operators five weeks to get it moving again. If it couldn’t wiggle its way out, the batteries would have died like it happened to its rover twin, the Spirit, in 2010.

Two of the key scientific instruments no longer work and the faulty flash memory has also limited its abilities. Nevertheless, it is still beaming back images to NASA, giving us an improved understanding of Mars.

While speaking with San Gabriel Valley Tribune, Mars rovers project scientist Matt Golombek commented: “Twelve years is a very long time to have this sort of a continuous presence. For a science team to be this involved, on a daily basis, for this long on Mars, is pretty much unprecedented.”

The space agency is planning to send a new rover to Mars in 2020.

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