Opportunity rover marks eight-year anniversary on Mars

January 25, 2012 is the 8-year anniversary of the Opportunity rover on Mars. The rover touched down on Mars at 5:05 a.m. UTC on January 25, 2004 (11:05 p.m. CST on January 24) for a planned three-month mission to explore the Red Planet. It was three weeks after its twin rover, Spirit, arrived on Mars. Eight years later, Opportunity is still kicking it. It’s essentially on a new mission, exploring the huge Endeavour crater on Mars, which it reached in August 2011 after a three-year, 4.8-mile trek from its previous post.

Opportunity landed in Mars’ Eagle crater, on the opposite side of the planet from Spirit. Both missions were expected to last three months. Spirit lasted an impressive six years before it stopped communicating with Earth in March 2010. Meanwhile, at the Eagle crater, Opportunity found evidence of “an ancient wet environment,” according to a NASA press release issued yesterday. It continued to find similar evidence from the same period in craters of increasing size before moving to the half-mile-wide Victoria crater, where it stayed until mid-2008, when Opportunity began its journey to the 14-mile-wide Endeavour crater.

The Opportunity rover is currently perched on a sun-facing slope of the Endeavour crater, aiming to maximize the amount of sunlight that hits its solar panels, which are currently coated in a thicker layer of dust than in previous winters. This is the rover’s fifth winter on Mars (Martian years are almost twice as long as Earthly years). In a video, John Callas, Mars Exploration Rovers Project Manager, likened Opportunity’s current perch on the Endeavour crater to positioning your beach chair in order to get the best suntan. Callas called Endeavour “a window further into Mars’ pass.”

Before moving to its current position at the edge of the Endeavour crater – an outcropping of rock informally dubbed Greeley Haven after the late Mars rover scientist Ronald Greeley – Opportunity explored a region known as Cape York. There, it discovered a high zinc content in the Martian soil, which is said to indicate the past presence of water. It also found hydrated calcium sulfate, which the mission’s principal investigator, Steve Squyres of Cornell University, Ithaca, New York calls “the clearest evidence for liquid water on Mars that we have found in our eight years on the planet,” according to the NASA press release.

In the video, Callas says there is no way of knowing how long the Opportunity rover will last, but space scientists will continue to use it as long as it works — and it appears to be still in solid condition.

In August 2012, Opportunity will (hopefully) be joined by a new, bigger, more powerful rover. This one is called Curiosity. The two rovers are unlikely to meet, though, as Curiosity will land on the opposite side of the planet. But as Spirit and Opportunity’s longevity has proven, you never know.

By the way, if you’re interested in seeing what Opportunity sees, you can download an app that allows you to view its images, which are updated daily. Simply search “Mars images” on your iPhone, iPad, or Android phone, and marvel.

Bottom line: The Mars rover Opportunity is celebrating its 8th anniversary of being on Mars today (January 25, 2012). It’s currently located on the edge of the Martian crater Endeavour, at a rock outcropping informally known as Greeley Haven.

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