The robot has been missing feared dead for the past eight months, disappearing amid an intense dust storm on the red planet.
As the thick dust whipped up and around the rover – and across the entirety of Mars – the sunlight that powers it was blocked and its batteries ran out.
Nasa issued a final set of commands to confirm the machine’s demise – the last in more than 1,000 messages sent in a bid to wake it up.
The space agency last night pronounced the rover officially dead after 15 years spent exploring Mars and carrying out ground-breaking science.
It was the longest-lasting craft on the planet, and team members are already looking back at Opportunity’s achievements, including confirmation water once flowed on Mars.
The six-wheeled rover was designed to travel just 1km but instead set a roaming record of 45km.
Its identical twin, Spirit, was pronounced dead in 2011, a year after it got stuck in sand and communication ceased.
Both outlived and outperformed expectations, on opposite sides of Mars.
The golf cart-size rovers were designed to operate as geologists for just three months, after bouncing on to the planet inside cushioning air bags in January 2004.
They rocketed from Cape Canaveral a month apart in 2003.
“I am standing here with a sense of deep appreciation and gratitude as I declare the Opportunity mission as complete,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate, in an online video presentation at the Jet Propulsion Laboratory in Pasadena, California, lat night.
“I stand here surrounded by the team, and I have to tell you, it’s an emotional time.”