It's definitely a sad day, but it's hard to be upset when you consider the incredible job Opportunity did during its lengthy Mars adventure, and NASA is more than pleased with everything it accomplished during its time on the Red Planet. These features form in water, a definitive sign to NASA that liquid water had been on the surface of Mars.
The craft, which arrived at the Red Planet in July 2004, has been out of communication since last summer. Michael Watkins, Director of NASA's Jet Propulsion Laboratory commented on the mission's broader contribution to society: "Spirit and Opportunity energized the public about the spirit of Mars exploration".
Opportunity was exploring Mars' Perseverance Valley, fittingly, when the fiercest dust storm in decades hit and contact was lost.
Despite NASA engineers' best efforts to get a response via radio channels, its last communication was on June 10, 2018 after more than 600 attempts since August.
Farewell, Opportunity. We'll miss you.
One theory for the rover not powering up again was that the dust storm left a layer of dirt and silt on Opportunity's solar panels.
The golf-cart-sized rover was only ever created to operate on Mars for 90 Martian days. It's been suggested by some on the team that Curiosity may not ever get the same life span, and Mars 2020 (you can guess when NASA intends to launch it) is a lot like an upgraded Curiosity.
Trundling along at five centimetres per second (0.1 miles per hour), Opportunity covered 28 miles of Martian ground in its time, and took a peek at numerous Red Planet's impact craters.
"And our beloved Opportunity remains silent", Thomas Zurbuchen, associate administrator of the Science Mission Directorate, told a news conference Wednesday afternoon. It also discovered evidence that there was once water on Mars, which may have been a possible breeding ground for extraterrestrial life.
Both rovers found plenty of evidence that Mars was relatively warm and wet long ago, with environments that could well have supported life as we know it. Spirit, for example, rolled through an ancient hydrothermal system, revealing that at least some parts of Mars also featured energy sources that ancient organisms could have exploited.
On Tuesday, InSight deployed its "mole," or heat flow probe, on the Martian surface, and in the coming weeks, it will be the first probe to go more than 16 feet below the surface. "But what I suppose I'll cherish most is the impact Opportunity had on us here on Earth".
From the beginning, Opportunity exceeded expectations and set records. These missions and the people working to keep them operating come with an important legacy of discovery, and each represents a milestone in space exploration. "Rest well, rover. Your mission is complete".
The rovers used a variety of instruments in this quest, including three different spectrometers, a panoramic camera and the high-resolution Microscopic Imager, which delivered magnifying-glass-like views of Red Planet rock and dirt.
"It is because of trailblazing missions such as Opportunity that there will come a day when our courageous astronauts walk on the surface of Mars", NASA Administrator Jim Bridenstine said.