“My battery is low, and it’s getting dark.” No, this is not a teenager’s text sent at 7:00 pm, but rather the last communication from NASA’s Mars Rover, Opportunity, or “Oppy” for short. Oppy was announced ‘dead’ on the 13th of February, after surviving well past her 90-day life expectancy to live over 14 years on the red planet, over 56 times her expected life cycle.

Oppy’s communications were cut off after a dust storm on the 10th of June last year. Since then, NASA scientists and engineers have been trying to contact her. Her final resting place is the western edge of the Endeavour Crater, a place known as Perseverance Valley. The last song played for her was Billie Holiday’s ‘I’ll be seeing you’.

Many people have been paying tribute, in the form of comics, artworks, and (obviously) memes.

Oppy’s last message of loneliness is possibly what made everybody so fond of her over the past week, but what did she discover in those 15 years, in the 45 kilometres she travelled, and the 217,594 photos she took? Her history, as you may expect, is fascinating.

A Brief History of Oppy

Opportunity landed on Mars on the 24th of January, 2004, three weeks after her twin Rover, Spirit. Spirit went silent on the 22nd of March, 2010, only 6 years after she and Oppy landed (still very good, considering they were supposed to last 90 days). It was Oppy who truly stood the test of time.

During her life on the Red Planet, Oppy discovered strange hematite formations that could only come about with the presence of water. These so-called “blueberries” (pictured below) were found in 2004 in the Eagle Crater and gave sure evidence that there had been water on Mars at some point in time. She studied stratigraphy at the Endurance Crater and set off to the Victoria Crater, which she circled for a year trying to find a path down into. After spending another year in Victoria, Oppy ventured back to Endurance and helped NASA to discover glistening veins of gypsum within the crater (another telltale sign of water). At the Endeavour crater, it discovered signs of water that may be drinkable like that in a lake or river here on Earth.

IDL TIFF file

After travelling 26 miles on Mars, the team at NASA named a valley in recognition of Oppy’s achievement: “Marathon Valley”. She marked her 15th year on the 30th of January this year.

Near the end of her life on Mars, over 1,000 transmissions had been sent to wake her up, at which point, her odometer was stable at 45.16km travelled, the furthest distance of any off-earth land vehicle. On the 20th of March, 2005, she set a one-day record for furthest distance travelled (220m), and reached the record of the longest drive on another world in 2014.  

Oppy also sent over 342,000 stunning, raw images to the Earth: fifteen of them 360-degree panoramas, some of them selfies, others of shadows and tracks through the dunes of Mars.

Oppy had already survived a mission-threatening dust storm in 2007, and the dust on the solar panels made it difficult to operate. She survived by managing power and activity until skies cleared enough to make normal progress again. The second dust storm took her out of operation in winter last year. In her last moments of contact with the pale blue dot, Oppy was serenaded. What NASA scientists played for her is in the following playlist.

And what of Oppy’s future? In 2020, NASA and the European Space Agency will be sending more rovers to Mars, with the aim of finding evidence of extinct microbial life. Maybe they can let us know how Opportunity is doing while they’re over there.

“It’s time to go home, Oppy” by Rostislav Shekhovtsov (@rostislav.shekhovtsov)