The Lightest Solid on Earth (You won’t believe this exists)

The aerogel shatters into thousands of pieces and turns to dust. But what’s surprising is that if I take those aerogel dusts and apply it to any surface, like my body, it becomes 100% hydrophobic. It makes me completely waterproof. On top of that, this dust also forms new non-brittle foam-like aerogel composites, which can be utilized in extreme applications requiring protection. Aerogels can be in different shapes; given that they are 99% air, can you guess the kind of sound would an aerogel make? Very metallic.

• So aerogel is this really amazing material.

• It’s the lowest thermal conductive solid in existence or the best insulation in the universe.

• This is the same stuff NASA uses to insulate spacecraft like the Mars Rovers.

• What is it made of?

• It’s just 99% air. In this case, that other 1% or so, is amorphous silica. The pores are only a couple of nanometers in thickness. Oh, yeah, Aerogel’s insulation capabilities are not its only remarkable property. It also exhibits both hydrophilic and hydrophobic characteristics.

• How is it possible?

Now we’re gonna sprinkle some aerogel powder on the water. Notice how the aerogel doesn't sink. It’s literally floating on the surface, creating a barrier. I’ll put it in the water. It’s in the water now. Thanks to the aerogel’s super hydrophobic properties, the match is still dry and lit. Wow. It’s amazing. The spoon is completely submerged, but it’s completely dry. I’m going to put some particles on. I wonder what would happen if I apply it to my whole body, would I be waterproof?

• Wow.
• That’s pretty cool.
• That’s awesome.

These ball-shaped droplets are not actually touching my hand. There is a layer of aerogel powder between my skin and the water. Wow. It feels like magic.

• Yeah, it really is.
• But what we will see when I cover my whole body with these particles will blow our minds. Let’s start.

Oh my god, this one is half-burned already. As you see, this setup is much more effective in terms of protecting this hamburger. And this one is on smoke. You see the difference. If this insulation is really that good, and if you’re using it to insulate spacecraft, why isn't it used to insulate everything here on Earth, right? From buildings to apparel. Turns out it has one major problem.

• I love that, that’s beautiful.

The challenge with aerogel since the beginning of time has been that this stuff is super brittle.

• And that’s what we do at OrosLabs or SolarCore.

• How do you make it not brittle so that you can use it in whatever application?

• So this is the solution you came up with?

• That's correct.

So this is a closed-cell foam combined with aerogel. Closed-cell foams are made from silica substance with a structure consisting of tiny, sealed air pockets. Before moving to the flamethrower test and test it on my entire body, we’ll make one small trial with this foam.

• If that falls, I have to take my hand immediately.
• Yeah, I’m quick.

You ready?

• You can crank it up as much as you want.

So... You’re seeing the impact on it. So, it’s very cold here, I can touch it as much as I want. It melted, look. Look at the shape of it, it used to be flat.

• You ready?

• I’m ready.

• Wow, wow! I can feel some heat from the sides. But nothing from the center. Can you get closer to me?

• That’s as close as I want it to get.

For those unfamiliar, liquid nitrogen is extremely cold, at a temperature of about -196 degrees Celsius.

• It wouldn’t be great if it came in contact with your skin.
• It would freeze your skin.
• Then my hand would be shattered.

Let’s see what this liquid nitrogen can do to something that is not protected by aerogel for comparison. Our next item on the list: a bunch of parsley. But this time, instead of submerging it, we'll directly spray liquid nitrogen on it.

• Even the bones are shattered. This could be so dangerous then.
• That’s pretty dangerous.

Behind me, Mike is ready to spray the liquid nitrogen directly at me.

• Okay, you guys are ready?
• 5,4,3,2,1.

This is amazing. I don’t feel it. Just on my pants, because some droplets came to my pants but that’s alright. But my upper body I don’t feel anything. I’m going to apply particles of aerogel on my body and get in the water and stay dry.

• So no health problems, right?

• No.

• Okay, feeling okay today?

• Yeah.

• You’ve obviously been in the water before, cold water.

• Yeah.

• Okay, perfect. We have everything else set up just in case.

• Systolic pressure: one hundred and thirteen.

I have a bucket of powdered silica aerogel and I’m evenly covering my whole body with that. Let's see if it can keep me dry even underwater. I’m completely submerging my body now. I am dry, this is a miracle guys. Particles are blocking the water coming onto my skin. Still nothing, nothing. Look at my leg. It's been in the water for quite some time. And it's dry. There are droplets on my leg. Let's get these out of my leg. I don’t even feel cold. I don’t even need that.

I will get inside a pool now and you’ll see how it actually looks underwater. Aerogel particles cause a thin, gray layer because they trapped tiny air bubbles on my body. These air bubbles reflect skylight, giving my skin a shiny, silvery appearance. You can notice some of these air bubbles coming off my legs and rise to the water surface. Air on my skin makes me feel lighter in the water. Completely dry.

How is that possible? It’s raining heavily now, but I don't get wet. I might be the only person caught in the rain completely covered in hydrophobic aerogel particles. If you look at it carefully, there are rain droplets on the surface of the pool water. That means rainwater and the pool water never meet; there is a layer of aerogel between pool and the rainwater. The aerogel powder that I applied onto my body was hydrophobic, but this one is hydrophilic. Watch what happens when I drop water on this aerogel.

As this type of aerogel can absorb moisture from the air, they are used in museums to protect artifacts or to safely store medicines without exposing them to humidity. Last but not least, aerogel’s nanopores are even way smaller than the visible light. The visible light ranges from 380 nanometers to 750 nanometers while the aerogel’s pores are only between 20 to 40 nanometers wide. Shorter wavelength particles, blues, purples, UV light, get scattered when they hit aerogel. And that’s what causes aerogel to look blue, the same reason the sky looks blue. It’s called Rayleigh scattering.

When we expose an aerogel to ultraviolet light, which has the shortest wavelengths, it scatters the light better, making the aerogel appear opaque. Now, when we switch to infrared light, which has the longest wavelengths of all, it passes right through the aerogel, making it appear completely transparent. To pass through more easily, especially in bright sunlight.

Ruhi Çenet was here.