NASA’s Opportunity rover first landed on Mars back when George W. Bush was still in his first term of office. And while Opportunity was only expected to last 90 “sols,” or Martian days, on the Red Planet, it has far exceeded NASA’s expectations and just logged its 5,000th sol on Feb. 17.

A Martian sol does not quite line up with an Earth day, as it is 40 minutes longer, and Martian years are twice as long as those on Earth. Opportunity landed on Mars 14 years ago on Jan. 25, 2004, and has been exploring the Perseverance Valley region near the Endeavor Crater. NASA gave the valley that name in honor of Opportunity’s incredible endurance.

The reason NASA only planned 90 sols was because they did not think Opportunity could handle the harsh Martian winter on its solar powered engine. However, they were wrong, and since then Opportunity has weathered a staggering eight Martian winters.

“Five thousand sols after the start of our 90-sol mission, this amazing rover is still showing us surprises on Mars,” said Opportunity Project Manager John Callas, of NASA’s Jet Propulsion Laboratory, Pasadena, California.