A self-portrait of NASA's Opportunity rover on Mars taken by the Microscopic Imager on the rover's robotic arm to celebrate its 5,000th Martian day in February 2018.
Credit: NASA/JPL-Caltech

In 2007, a dust storm on Mars covered the entire planet and forced Opportunity to hunker down for two weeks in a sort of survival-mode of minimal operations. To save power, the rover went days without phoning home to its controllers at NASA's Jet Propulsion Laboratory in Pasadena, California.

It was during that 2007 storm that Opportunity's handlers worried about the rover's ability to power its vital survival heaters with the low power levels caused by that dust storm. But Opportunity survived.

In fact, Opportunity has been surviving for 15 years.

The rover (and its twin Spirit) launched separately to Mars in 2003 and landed in January 2004 for what was originally scheduled to be a 90-day mission. But like the dust storm now battering Opportunity, the rover's mission ballooned from 3 months to 15 years, 14 of them on the Martian surface.