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It finally happened. Last week, after eight months of listening and hoping, NASA and the entire world had to say goodbye to the Opportunity rover on Mars. [sniff] I'm not crying; you're crying.

The end of the mission was thanks to a planet-wide dust storm that started last May and obscured the Sun for months. It blocked too much light for too long, which prevented Oppy's solar panels from charging its batteries and keeping its internal electronics warm enough to work. NASA first lost contact with the rover back in June, and despite sending it thousands of signals, and even accounting for the possibility of things like broken radios, they just never heard from it again.

So last Wednesday, the team decided it was officially time to put the rover to bed. Now, Opportunity stands as a monument to human achievement. But even though we've officially had to say goodbye, that hasn't stopped some people from wondering if we'd tried harder, could we have saved Oppy?

The short answer is not really, at least, not unless engineers had designed the rover differently from the beginning. Since Opportunity was mainly powered by solar panels, it was always at the mercy of giant dust storms like this. And since there aren't any other rovers nearby, it's not like we could have sent something over to brush it off.

So even from the start, engineers knew that a bunch of dust would be bad news. Now, if Oppy had been powered by nuclear energy, like the Curiosity rover, it would have survived, no problem. But back when Opportunity was designed, solar panels were really the only viable option.

Even today, the type of plutonium that Curiosity uses to charge its batteries is in super short supply, the majority of it actually came from making nuclear weapons during the Cold War. So back when Opportunity was being built, NASA primarily used it for deep-space missions, like the Voyagers or New Horizons. Opportunity was given a tiny bit of plutonium to generate heat, but that was mainly to help supplement the electrical heaters, which were powered by solar panels.

I mean, to be fair, Oppy was originally made for a 90-day mission, so it's not like it needed a bunch of plutonium. And really, even if this storm had never come along, the rover would have died eventually. Its batteries were slowly becoming less and less efficient, so even if the skies on Mars had stayed beautiful and clear, Opportunity would have eventually lost power.

So one way or another, our rover wasn't going to last forever. But that doesn't take away from the fact that it did amazing work during its 15 years of operation. Opportunity was the first rover to identify sedimentary rocks on another world, and it discovered what came to be called “blueberries”.

They're gray spheres of a mineral called hematite that formed from acidic groundwater. And speaking of water, Oppy also found veins of gypsum at the rim of a crater, which were likely deposited by water, along with clay minerals in the crater that suggest it could have been hospitable to life. And in the end, it sent us over 200,000 images that will produce even more science and inspire us for years to come.

Oh, and all of this was despite a lot of setbacks. While it was on Mars, Opportunity got trapped in a sand dune, survived another planet-wide dust storm, lost steering capabilities of its two front wheels, and also lost the ability to use its flash memory. So it's kind of poetic that its final resting place is near Mars's equator in a place called Perseverance Valley.

For more than a decade, Opportunity has been one of our best tools for understanding Mars, and the scientists who drove it and analyzed its data have made the best of a lot of tough situations. But the good news is, even while we're mourning the loss of Opportunity, we can still look to humanity's other efforts to understand the Red Planet, too. For example, the Curiosity rover is still ticking and making new observations all the time.

And NASA's InSight lander recently finished setting up its suite of instruments on Mars to study what's going on underneath the planet's surface. And there are two more rovers in the immediate works as well. The ESA's Rosalind Franklin will explore an area near the Martian equator after it arrives in 2021.

And that same year, NASA's currently-unnamed Mars 2020 rover is set to land a bit farther east. So even though the Opportunity rover is shut down for good, there's a lot to look forward to on Mars. And maybe one day, when we start sending humans to the Red Planet, we'll be able to brush off the dust and tell Oppy how it exceeded our expectations and did a good job right up until the very end.

If you want to keep up with all of these missions, and the discoveries we're going to make, follow along by subscribing at youtube.com/scishowspace. And as always, thanks for watching this episode of SciShow Space News! [♪ OUTRO].