The space agency, which has sent over 1,000 recovery commands to the rover, tried to reach the vehicle late on Tuesday evening. If there's no response by Wednesday – which NASA suspects will be the case – Opportunity will be declared dead, 15 years after arriving on Mars.
A press conference to discuss the rover’s status is scheduled for Wednesday afternoon.
Lost in an epic dust storm that enveloped Mars and prevented sunlight from reaching its surface, the last signal received from the $400 million solar-powered rover was on June 10, 2018.
The missing vehicle was spotted three months later. On Sept. 20, the HiRISE high-resolution camera on NASA's Mars Reconnaissance Orbiter captured an image of the rover in Mars’ Perseverance Valley. However, scientists were still unable to talk to the vehicle.
Nonetheless, team members have been looking back at Opportunity's achievements, including confirmation water once flowed on Mars. Opportunity was, by far, the longest-lasting lander on Mars. Besides endurance, the six-wheeled rover set a roaming record of 28 miles.
Opportunity landed on Mars on Jan. 24, 2004 PST, just three weeks after its identical twin, Spirit, reached the Red Planet’s surface.
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 onto our planetary neighbor inside cushioning airbags. They rocketed from Cape Canaveral a month apart in 2003.
Spirit was pronounced dead in 2011 a year after it got stuck in sand and communication ceased. It's no easier saying goodbye now to Opportunity than it was to Spirit, project manager John Callas told The Associated Press.
"It's just like a loved one who's gone missing, and you keep holding out hope that they will show up and that they're healthy," he said. "But each passing day that diminishes, and at some point, you have to say 'enough' and move on with your life."
NASA has two other probes operating on Mars. The Curiosity rover, which reached the Red Planet in August 2012, has more than 12 miles on its odometer. NASA’s Insight Mars Lander reached the surface of the Red Planet in November 2018, ending a journey that lasted six months and more than 300 million miles.
Mars looms large in America’s space future.
NASA’s long-term goal is to send a manned mission to Mars in the 2030s. However, former astronaut Buzz Aldrin thinks that a slightly later target date of 2040 is more realistic. In an interview in 2016, the Gemini 12 and Apollo 11 astronaut told Fox News that by 2040, astronauts could have visited Mars’ moon Phobos, which could serve as a sort of stepping stone to the Red Planet.
In November 2018, NASA announced that it has selected the location where its Mars 2020 rover will land on the Red Planet. The rover is expected to land on Mars Feb. 18, 2021.
Fox News’ Chris Ciaccia, Samuel Chamberlain and the Associated Press contributed to this article.
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