SpaceX seems like they’re always in the news, whether it’s for landing rockets or exploding rockets or planning to send people to the Moon.

But this week, they accomplished another first in the history of spaceflight: They’re the first private company to ever reuse a rocket big enough to send things into orbit. And if they can keep doing it, the cost of getting to space could drop by a lot over the next few decades.

It costs tens of thousands of dollars for every kilogram you send into space. But a lot of that price tag doesn’t go toward fuel, like you might expect. Building rockets is expensive, and each flight generally gets a brand-new one.

The only program to reuse orbital-strength rockets was the Space Shuttle, and it still didn’t reuse all of its parts — it needed a new one of those giant orange external tanks for every flight. But back in 2015, SpaceX started trying to land rockets’ first stages, the biggest and most expensive part of the rocket, on drone ships out in the ocean. There were a couple of early failures, but since then, they’ve had a pretty solid track record of landing rockets exactly where they want to — whether that’s on a ship out in the ocean, or on a launch pad on land.

They still don’t land every part of the rocket, but they can recover far more than any other company has before. And last week, after months of repairs and safety checks, they refilled a rocket that landed last April, strapped a communications satellite to the top, and sent it back into space. No company’s ever reused an orbital-strength rocket before, and they did it less than a year after the first launch.

In typical SpaceX fashion, they also landed the reused rocket, although they won’t be using it a third time — they’re just planning to put it on display. Again, no one had ever landed a rocket like this before SpaceX did it in 2015, and now it’s becoming this normal, routine thing. The mission didn’t go completely perfectly, though.

For the first time, SpaceX also tried to recover the $6 million payload fairing — the cone at the top of the rocket where the satellite sits on its way up. They attached a parachute and some thrusters to help stabilize it on the way down, but they only got half of it back intact. Still, not bad for a first try!

SpaceX founder Elon Musk says the next goal is to go from landing to relaunch in less than 24 hours. Like a lot of what he says, it’s a pretty ambitious target. But the guy’s basically Tony Stark, so I wouldn’t doubt him just yet.

SpaceX eventually wants to send humans all the way to Mars. But even though we’ve never sent people there, we have sent lots of robotic explorers. And one of them, the Mars Reconnaissance Orbiter, or MRO, just completed its fifty thousandth orbit around the Red Planet.

And it’s still going strong! The MRO has accomplished some pretty remarkable things since arriving at Mars back in 2006. It’s photographed over 99 percent of the Martian surface, including high-resolution shots of about 3 percent.

All those pictures have created incredibly detailed maps that scientists use to watch for environmental changes over time and to find safe landing targets for rovers like Curiosity. The high-resolution photos also showed why the Phoenix lander stopped working back in 2010. It might not look too impressive in an image like this, until you remember that the lander was less than 6 meters across and these pictures were taken from orbit.

Scientists saw that the lander’s solar panels were damaged by the Martian winter and fell off -- something they might never have known for sure without the MRO’s eye in the sky. And speaking of landers and rovers: We wouldn’t have heard nearly as much from them without the MRO. It can process and transmit data ten times faster than anything else around Mars, so it acts like a booster for signals between Earth and the rovers and landers all around Mars.

Ever marvelled at data sent back by a rover like Curiosity or Opportunity? You probably have the MRO to thank for it. And then there are all of the MRO’s other scientific instruments, which have revealed just how diverse Mars’s surface is, and how watery it used to be a couple billion years ago.

Because of the MRO, we also discovered that Mars still isn’t completely dry: Back in 2015, MRO was the first spacecraft to detect direct evidence of water flowing on the Martian surface. And with its instruments working as well as ever, the MRO shows no signs of slowing down. Just last month, the MRO measured the age of one of Mars’s biggest volcanoes, sent back stunning pictures of a canyon longer than the United States, and watched a pair of dust storms sweep across the planet.

So 50,000 orbits in, the MRO is still teaching us more about our planetary neighborhood every day. Can’t wait to see what we learn in the next 50,000! Thanks for watching this episode of SciShow Space News, and thanks especially to our patrons on Patreon who help make this show possible.

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