NASA's Mars Opportunity rover recently celebrated its 11th anniversary on the Martian surface, marking the milestone with a stunning panorama that doubles as a moving tribute to the victims of the 9/11 terrorist attack in New York. Over the course of its tenure on the Red Planet, the tenacious explorer has broken the record for the longest distance traveled on another world, making countless groundbreaking discoveries along the way.

Opportunity's original mission was only scheduled to last 90 days, during which time it would scour the terrain near its landing site in Eagle Crater for any clues that would point to the existence of liquid water on ancient Mars. Over a decade later, Opportunity is still going strong (albeit with some memory problems), with last year seeing the audacious adventurer overtake the Russian lunar rover Lunokhod 2 to take the crown for the most miles traveled on another planet, racking up an impressive 25.9 miles (41.7 km).

In order to capture the image, Opportunity has ascended 440 ft (135 m) since traversing a low-lying section of the Endeavour Crater known as Botany Bay in mid 2013. Cape Tribulation represents one of the highest altitudes that the rover has visited, allowing it to image a large portion of the interior of the Endeavour Crater, in addition to the rim of another crater positioned close to the horizon, in a single panorama.

The image itself is a bleak but beautiful reminder of the rover's achievements, and could almost be mistaken for plain and uninteresting until you remember that you are looking at an image of another world, upon which no human being has ever set foot. However, the panorama is more than just an anniversary marker, it is also a memorial.

The aluminum used to create the housing for the rover's rock abrasion tool (pictured in the bottom right of the panorama) had been salvaged from the wreckage of the Twin Towers prior to the rover's launch in 2003. The American flag emblazoned on the protective casing stands on Mars as a perfect example of what a people can achieve when they stand united against adversity, and constitutes a touching memorial for those who lost their lives on that tragic day.

Source: NASA

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