"I am standing here, with a sense of deep appreciation and gratitude, to declare the Opportunity mission as complete, and with it the Mars Exploration Rovers mission as complete", said Thomas Zurbuchen, NASA associate administrator for science.
Opportunity exemplified this mobility, travelling over 45km across the Martian surface.
Opportunity found hematite at its landing site: little round things all over the ground that looked like blueberries. At that time, it was planned for the rover to travel no more than 1km on a 90-Martian-day mission.
Three more landers - from the U.S., China and Europe - are due to launch next year.
Later evidence gathered at Endeavour Crater indicated that the water at that location in ancient times might have been drinkable.
Opportunity landed on Mars in January 2004, a few weeks after its rover twin, Spirit. Without electricity from the solar cells, the spacecraft's batteries could not recharge and power levels presumably fell below the minimum needed to keep the rover's computer and its master clock operating.
You may be interested to know that Opportunity was powered by VxWorks on a 20MHz IBM RAD6000 CPU - a RISC Single Chip based on Big Blue's POWER1 architecture - with 128MB of RAM, 256MB of flash memory, and 3MB of EEPROM storage.
"[Opportunity] has given us a larger world", Dr Callas said. Opportunity examined the first extraterrestrial meteorite and traveled 28 miles across the Meridiani Planum, which the mission crew affectionately called a "marathon", setting a new record for longest distance of any off-Earth terrain vehicle.
Opportunity rover led a grand life on the Red Planet.
For months, Callas and his colleagues hoped that Opportunity kept enough power in reserve to wake itself up and get back in contact with Earth.
"Science is an emotional affair, it's a team sport, and that's what we're celebrating today", he said.
The MER mission also changed the way scientists thought about solar system exploration.
Even if it was officially pronounced dead, its legacy would endure for years to come.
Opportunity was exploring Mars' Perseverance Valley, fittingly, when the fiercest dust storm in decades hit and contact was lost. That included finding evidence of past water on Mars that had a neutral pH, rather than acidic.
Opportunity had been roving the surface of Mars for 15 years before the ominous, giant global dust storm that sealed its demise came along. "Now she can rest, beneath a thin layer of dust, knowing she did humanity proud", Tanya Harrison, director of research for the Space Technology and Science Initiative at Arizona State University and science team collaborator on Opportunity, told Astronomy. "Whatever loss we feel now must be tempered with the knowledge that the legacy of Opportunity continues, both on the surface of Mars with the Curiosity rover and InSight lander and in the clean rooms of [NASA's Jet Propulsion Laboratory], where the upcoming Mars 2020 rover is taking shape".
Bridenstine liked that idea: "Bring 'em all back", he joked. "They were our eyes and ears, our remote robot bodies". In Squyres' view, that would be the most fitting tribute to Spirit and Opportunity. "And they see us on TV jumping up and down like we just won the Super Bowl". That's the place they were created to go.