[ intro ] 2020 marks two decades of  people living and working aboard the International Space Station.

And in those twenty years, they’ve been busy! The scientists aboard the ISS have done   thousands of experiments.

And some of  the things they’re studying up there — well, they’re not what you might  picture astronauts thinking about. Because they’re not just  studying stars and galaxies:. They’re also making fireballs,  solving mysteries about lightning, and even growing parts that could  power the next generation of computers.

Let’s start with fireballs. Because  I know what you’re thinking: Fire in an enclosed area that’s whipping around  the Earth at almost eight kilometers per second… is a bad idea. And normally, it is!

But if we’re  serious about preventing fires in space, we need to know what fire  acts like in microgravity — because it’s pretty unique. On the ground, a fire gets most  of its new oxygen from convection. That’s where warmer, lighter air  rises in the middle of a flame and makes a gap for cool air  to flow in from the sides.

But in orbit, there’s no concept of  weight, so warmer air isn’t lighter. That means it doesn’t rise,  so there’s no convection. Instead, oxygen reaches the  flames through diffusion, where new gas slowly works its way from the  outside of the flame ball to the center.

And yeah, I said “flame ball!” Because  without the moving air from convection, fires in space are also spherical. We’ve known about all this for  decades, thanks to various experiments. But having a permanent lab in the ISS has  let us learn how to apply this knowledge.

Since 2011, researchers on the  Station have been working on the. Burning and Suppression of Solids investigation. In it, researchers put a test material in  the fireproof Microgravity Science Glovebox.

Then, they light it on fire,   let it burn, and eventually blast  some fire suppressant into the box. It’s simple, but it’s taught us a lot. Like, these tests have shown  that without convection, heat doesn’t move away from materials  as fast as it does on Earth.

So some things can be more flammable in space — including some cotton-based fabrics! That’s the sort of thing we want to  know as we’re planning what clothing and equipment to bring on future missions. So, by making a few  carefully-controlled fires now, we’re preventing surprise fires in the future.

Next, being in orbit also gives the ISS an  unmatched view of pretty much everything, including thunderstorms. And that’s great, because even though  thousands of storms happen every day, there’s a lot we don’t know about them. For instance, we’ve known for years that  storms make gamma rays in what are called TGFs, or terrestrial gamma-ray flashes.

Theoretically, we could use these flashes  to make more robust weather predictions. But first, we had to figure out  where they actually came from. And that didn’t happen until 2019,  thanks to instruments on the Space  .

Station’s Atmosphere-Space Interactions Monitor. It was added to the Station in 2018, and it lets us study how lightning’s energy  spreads through the upper atmosphere. It’s also able to look at lightning and  TGFs at the same time, which was new for us.

And that helped us figure out  where these lights come from. According to work presented at an  international geophysics conference,. TGFs form in front of a lightning bolt.

Based on data from the Interactions Monitor, the researchers concluded that as an  electric field goes through the air, it interacts with molecules in the atmosphere and  causes them to shoot out a bunch of electrons. And we see those electrons as gamma-ray flashes! Now, the next step is to figure out if we really  can use TGFs to better predict the weather.

But for now, just knowing more about where those  lights come from has given us a big head start. It will take time for research into fires and  lightning to directly impact life on the ground. But ISS experiments with crystals   could have a direct impact on how  you’re able to watch this video.

A crystal is a solid with a regular,  repeated arrangement of atoms. And they’re useful in building all kinds of tech,  including the chips used in semiconductors — which are super common in electronics. The trouble is, growing  crystals is a delicate process.

Generally, it either involves  letting a liquid freeze, or letting solids suspended in  a liquid build up on a surface. And even something as simple  as heat can mess that up. Like, if one part of a liquid  gets cooler than another, it can start sinking and disrupt everything.

That’s convection at work again,   and it’s the opposite of how  warmer, lighter air rises in flames. In this case, it’s just  cooler, denser liquid sinking. And here, that sinking can lead  to lumps and bumps in the crystal, or it can make the atoms more neatly-arranged  in one direction than another.

Right now, that means chips often have minor  imperfections that slow the machine down. But space research could help with that. Researchers have been studying the crystals  in semiconductors on the ISS since 2002, as part of the SUBSA program.

The tests involve watching how crystals form and change in microgravity with different  temperatures, time limits, and more. And they’ve shown us that crystals  grow so much better up there. Since there’s no sense of weight and no convection  in orbit, crystals can grow perfectly uniformly.

And now, scientists think we can harness that  information to build better chips on Earth. Others are even imagining a whole new  industry of chips grown in orbit for the world’s best computers and instruments. So, 20 years ago, we had high hopes  for the International Space Station.

But having a permanent laboratory in orbit  has deepened our understanding of the world in ways probably no one could have predicted. If you want to keep celebrating the Station’s  twentieth anniversary with us, good news! For our November pin of the  month, we made ISS pins!

They’re shiny and lovely, and only  available this month. Starting in December, we’ll have a brand-new design. If you want to get one for yourself,  you can head over to DFTBA.comSciShow. [ outro ].