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Hot off the presses, this week has been cool! Researchers have discovered the first room-temperature superconductor, and another group has created a type of paint that actually stays cooler than the environment around it!

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[♪ INTRO].

A new study published in the journal Nature has announced the discovery of the first room-temperature superconductor! I know, this is big news!

Every other superconductor we know of requires subzero temperatures. If we had superconductors that worked just like, all the time, not only would electricity be super cheap, we could all be zipping around on levitating trains; even have legit hoverboards! Of course, as you probably expect, there is one big caveat to this new material, which is why it’s not quite ready for everyday use.

But I’ll get there. A superconductor is a substance that conducts electricity with no resistance. That means an electric current can flow through it without losing energy along the way.

And given how much electricity we all use, I mean like, you’re using some right this very second just to watch this video, well, you can imagine how useful it would be to have super energy-efficient electricity. Plus, superconductors do much more, because they allow us to make very powerful magnetic fields. So, think better particle accelerators, smaller and less expensive MRI machines, super-efficient magnetically levitated trains.

But, the superconductors we know and love all have one catch: they only work at extremely low temperatures. The first, discovered in 1911, only super-conducted when it was near absolute zero, or −273.15 degrees Celsius. And while researchers have now found substances that can handle things a bit warmer than that, no superconductor has ever worked reliably above freezing until now.

The details of this study sound like something straight out of an Iron Man movie. They squeezed together powdered carbon and sulfur at extremely high pressures, exposed them to hydrogen gas, and then shot the whole thing with a laser. And, after a series of adjustments to the laser and pressure conditions, they witnessed the formation of a transparent crystal substance that conducts electricity with zero resistance: a superconductor!

Amazingly, this superconductor works at temperatures as high as 287 Kelvin, or about 15 degrees Celsius. Now, that might not be quite as warm as some of us like our rooms, but it’s warm enough to count as room temperature, and it’s a lot better than freezing! Now, before we get too excited about a whole new technological era here, there are some caveats.

Well, there’s one big caveat, really. This material only superconducts under pressures of about 267 gigapascals. That’s roughly two and a half million times the pressure we normally experience under the atmosphere, so it’s not exactly ready for household use.

The next big step is for the researchers to figure out exactly what they’ve created. Because they actually don’t know. All they know is what it’s composed of.

The fact that it only exists under extreme pressure makes it hard to determine its molecular structure. But once they figure that out, they will be a big step closer to creating better versions. And already, this study shows that one of the major limitations of practical superconductors, temperature, isn’t a guaranteed limitation.

Whoever discovers how to break down the other barriers will revolutionize how human society uses technology and electricity; so, you know, no pressure. Now, while those scientists were warming things up, the researchers behind another new study in Cell Reports Physical Science were busy keeping things cool. They created a new type of paint that actually stays cooler than the environment around it.

Now, this could be a big deal because we pump a lot of energy into cooling things down. And when we do, we contribute to the steady increase of global warmth, which just makes the problem worse. So for about 50 years now, scientists have been trying to develop paints that help with passive radiative cooling; basically, paints that are so good at reflecting the sun’s light and heat that they actually cool things down.

But while the paints created up until now were super reflective, they still weren’t able to reflect enough light to stay cooler than their surroundings in the hot summer sun. That’s likely because they’ve relied on metallic components like titanium dioxide, which do reflect a lot of light but tend to absorb really high-energy UV light. This paint is made of calcium carbonate instead; the same substance found in the shells of sea creatures and in rock formations around the world.

It’s normally a bit less reflective than those metals. But, the researchers created a bunch of differently-sized particles of the stuff and then packed them into an acrylic paint base. And because of the concentration and range of sizes, they ended up with a paint that reflects 95.5% of the sun’s radiation!

Other paints typically top out at 90%. But most importantly, when the researchers tested their paint outside, they found that even under the noon sun, it stayed almost 2 degrees Celsius cooler than ambient temperatures. So there’s maybe a joke here about watching paint dry, but this is actually exciting!

If we painted all of our buildings with this kind of cooling paint, specifically buildings with really large, large roofs, like warehouses and box stores, that could go a long way towards offsetting how much we rely on air conditioning, which would conserve energy and help protect the environment. And because it relies on such a common and inexpensive substance, this paint wouldn’t actually be super expensive to make, so it could be pretty affordable. Next up, these scientists want to do some longer-term tests to see how the paint will hold up over time when exposed to light, dust, water, differences in temperature, other outdoor complications.

Still, even if it turns out it needs to be refreshed often to stay effective, this paint is pretty cool. Thanks for watching this episode of SciShow News. I have one more piece of news for you this week:.

We have a new host joining the SciShow family! Normally, I would have Rose in the studio with me in person. But, since we’re social distancing, we can’t do that.

But we can do it through technology! So Hello Rose! Why don’t you introduce yourself? [Rose] Thanks Hank!

Hello! I’m Rose Bear Don’t Walk and I’m so excited to join the SciShow team to help bring you all kinds of weird science and hopefully inspire you to learn along with me. I was born right here in Montana, and I’m especially interested in the relationship between people, plants, and public health.

My ancestors, the Salish people, used to eat hundreds of native plants that aren't very popular anymore. So I want to learn more about our traditional foods and how they might help people live healthier lives. [Hank] I also heard that you are a blue belt in Brazilian jui-jitsu?! [Rose] Why, yes I am! I can show you the next time we’re in the studio together.

I know some great submission holds. [Hank] Ahh, it’s really a shame that that won’t be any time soon. Anyhow, Rose’s first video will be coming out next week, so keep an eye out for that! In the meantime, thanks for watching SciShow News! [♪ OUTRO].