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A private company has been approved to land on the moon!

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Hank: Your upcoming tour of the Moon just got a little bit closer. Because for the first time in history, a private company just got the go-ahead from the US government to land on the Moon. Moon Express, a company based in Florida, wants to land on the moon by the end of next year.

If they can get their lander to travel 500 meters and send photos and video back to Earth, they’ll win Google’s Lunar X-Prize, which comes with a $20 million reward. But Moon Express’s long-term goal is much more ambitious: they want to develop the resources on the Moon. That means mining for things like water — from ice — and helium-3, a type of helium that’s rare on Earth but more common on the Moon. Water is — well, it’s water.

If we’re going to live on the moon one day, it’s easier to dig it up there then to take it with us. And helium-3 is handy because it could be used as a source of safe and efficient nuclear power. So eventually, mining these resources could help establish a foothold on the moon for future colonies.

Technically, it is legal for a private company to go to the moon. An international treaty that governs outer space just says that if a private company wants to go to space, the appropriate government has to approve and supervise them. But no private company has ever left Earth’s orbit before, and the approval process for it simply didn’t exist.

It took Moon Express 15 months to get permission, but now that it has, it’ll probably be simpler for other private space missions to get approval in the future. That’s important, because Moon Express isn’t the only one with their eyes on the Lunar X-Prize. Some 16 teams want a piece of the action. Plus, SpaceX has plans to launch its Red Dragon mission to Mars as early as 2018. So this first step could lead to a lot more trips past Earth’s orbit.

380 light years farther from home, in the constellation Scorpius, astronomers have taken a second look at a star system called AR Scorpii. In a paper published this week in the journal Nature at the end of July, the researchers announced that this star system is like nothing they’ve ever seen before. When observers first discovered Scorpii 40 years ago, they found that it varied in brightness about every three and a half hours. They labeled it a standard variable star and moved on with their lives. The brightness of ordinary variable stars can change for all kinds of reasons — like if they grow or shrink.

Then, last year, a team of both professional and amateur astronomers went back for a closer look at Scorpii, and realized it wasn’t that simple. Within that 3.56 hour cycle, there was another level of variability happening on a much shorter time scale. The light could change by a factor of 4 within 30 seconds! This behavior is more consistent with a binary star system than a single star. But it gets even weirder.

AR Scorpii is made up of a red dwarf star and a white dwarf star, and one of them is sending particles zooming straight at the other. That white dwarf is about the same size as Earth, but 200,000 times more massive. The red dwarf is much less massive, at only a third the mass of our Sun.

That white dwarf star is spinning so fast that it completes a rotation in just under two minutes. That’s fast, but it’s slowing down over time, which leaves a whole lot of energy available to spew into space, including straight at its partner star. How this translates into bursts of light we can see from Earth isn’t clear yet.

The white dwarf seems to be accelerating electrons to nearly the speed of light. It’s not clear whether these electrons come from the red dwarf or the white dwarf, but they’re excited by the white dwarf’s magnetic field. Those electrons give off wavelengths of light we can detect, and when electrons bombard the surface of the red dwarf, they might be causing a flare of visible and UV light.

As the stars rotate and revolve around each other, the amount of light we can see from Earth changes -- rapidly, but predictably. And this is the first time we’ve seen stars behave like this. So it turns out that there’s a lot you can learn from the way one star system twinkles.

Thank you for watching this episode of SciShow, brought to you by our President of Space, Morgan, and The Big Try Hard. Morgan completed a bicycle trip across the U.S. raising money for YouTube channels he loves. Thank you, Morgan! You can catch up on his journey at If you want to help support this show, just go to And don’t forget to go to and subscribe!