(Intro)

On September 2nd, three astronauts launched to the International Space Station in a tiny Soyuz capsule. That's pretty normal; new crew members head to the station every few months. But there was something a little different about this launch. It took two days for the astronauts to get there instead of six hours, because the station had to move in order to dodge some space debris.

Even under normal conditions, docking with the ISS while it's moving along at more than 27,000 kilometers per hour is tricky. There's so little room for error that until 2013, the standard procedure was to take two days- or 34 orbits of the earth- for a Soyuz capsule to get precisely lined up with the station.

But then in 2013, engineers developed a plan that got the capsule to the dock in just six hours (or four orbits), as long as the launch was timed exactly right and the ISS was in the perfect position. Since then, most trips to the station have used that expedited plan with a two-day version as a fallback in case something went wrong, and wrong something went!

Back on July 25th, NASA's tracking system warned that one of the thousands of pieces of shrapnel from a satellite collision in 2009 would be coming within 50 kilometers of the station. So they did an engine burn on the ISS that took it 900 meters higher, throwing off the calculations that would let the astronauts launching on September 2nd take the six hour version of the trip.

But the new crew of three finally got there, bumping up the space station's current population to nine. Now in this case a couple days of extra time was only a minor inconvenience, but debris is a big problem for the space industry. All sorts of leftover pieces from accidental explosions, ditched rocket stages, even broken satellites, are floating around up there. At this point we're talking more than half a million objects bigger than a marble zipping along at thousands of kilometers an hour. Space agencies keep track of the biggest pieces, but it's tough to follow the smaller ones. At these speeds, even flecks of paint can be dangerous.

So scientists have been working on ways to get rid of some of that debris, and one tool that could be perfect for the job: space lasers. 'Cause if there's one thing that lasers are really good at- aside from pointing to your PowerPoint presentation- it's burning stuff.

And in a new paper published in the journal Acta Astronautica, a group of European scientists says they have figured out exactly what we need to get the job done. Lasers first of all shootout beams of radiation. Those beams can be really intense and do some serious damage, or they can just be like a lot of fun for your cat. We're talking about the serious damage kinds. But even that kind of laser would only burn off small bits of the junk, not enough to make the whole thing disappear.

Still it could be enough to knock a chunk of metal into a collision course with Earth's atmosphere, which would finish the job. Problem is, lots of governments are wary of having ground lasers that are powerful enough to burn things in space, so you'd have to send the lasers to orbit. And the full mission model proposed in the new study addresses a lot of the difficulties that would come with putting a big powerful laser in space.

The study looked at factors like how a laser's power changes its performance, and how much energy a space-based laser would need to get the job done. And it turns out that just one laser in orbit with a range of 20 kilometers could lower the density of space debris by a fifth within 10 years. With those numbers, the researchers say it's probably worth looking into a laser-based junk destroying mission to make our astronauts and space ships a little safer.

Also in the news of dangerous "burny" science, there's a partial solar eclipse coming up on September 13th. But you only get to see it if you live in Africa, south of Angola, in the southern half of Madagascar, or in the eastern part of Antarctica.

Solar eclipses happen when the moon passes in front of the Sun from our perspective, blocking it from view. This month's eclipse is partial, meaning that the moon won't be exactly centered on the Sun, so the Sun will look like a crescent instead of being entirely dark.

But if you happen to not be in the few places where the solar eclipse will be visible, you might get to see a different and rarer eclipse this month too, a lunar eclipse, where the Earth's shadow makes the moon look darker. For the first time since 1982 it will be a super moon eclipse, meaning the moon will be at its closest point to earth, so it'll brighter and about 14% bigger. You'll be able to see at least part of the lunar eclipse if you're anywhere east of Siberia and west of India, so if you're there take a look at the sky around 2:47 a.m. UTC on September 28th, because the next super moon eclipse won't happen until 2033.

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