this is ferrofluid. It's made of tiny particles of iron-containing compounds suspended in oil. The particles are so small that normal Brownian motion (the jiggling of atoms and molecules) keeps the particles suspended in the oil, never settling. When you expose ferrofluid to a magnetic field, it forms spikes like a porcupine. These spikes form in order to align with the magnetic field lines. It takes less energy to form these spikes than to lay flat. This is the same reason why when you put these steel coins on a magnet, they don't want to lay flat but they want to stand up straight. Now, these spikes on the ferrofluid used to be just a fun novelty, but scientists at Michigan Tech want to use these spikes for something a little more useful, like space propulsion. Normally, we use combustion to propel objects and satellites into space, but for smaller devices, it's very difficult to make tiny rockets that work well. So, we have to think of different ways to propel something forward. Combustion works well because it can

make extreme pressures that send hot gases out the nozzle in One Direction, while the spacecraft moves the opposite direction. The faster you can Propel the gas in the opposite direction, the more momentum you have to move your spacecraft. But combustion produces large forces, and it works well for getting an object moving fast enough to orbit Earth or leave Earth, but it doesn't work very well for tiny little adjustments. You need micro thrusters for that. One way to propel something at very high speeds is with the electrostatic force. For example, I can charge this needle with oil in it up to thousands of volts and then aim it at this aluminum foil that has the opposite charge. I put my oil in, turn on my charge. Watch What Happens. There it goes. Look at the fine spray. The reason this is happening is because on pointy edges on things that are charged to high voltages, there's an extremely large electric field right at the tip. This causes all of the oil that's at the tip to have the same charge and be repelled from the other

oil around it so it forms tiny micro droplets of oil that fly away from the tip of the needle at high speeds. So there's a slight force on the needle, pushing it in the opposite direction. So to make this design be useful for propulsion, you can design it where there are drops accelerated through a Charged hole and then shoot out the other end while the spacecraft moves the opposite direction. But this design still uses needles, which aren't very scalable when you want to make small little spacecrafts like this one. This is called a cubesat; it's a miniature satellite. Now over 4,000 of these tiny spacecrafts and others like this have been launched into space and are orbiting us right now. They're very small, and the designs are getting even smaller, so there needs to be a way to make these propulsion systems tiny with less parts. So scientists at Mission can Tech have come up with a design that uses ferrofluid that can self-assemble into needles that can then be used as the propulsion.

material. Let me show you. So, I just have a magnet taped under my table here to create the magnetic field. You can already see it assembling into these needle structures. So, we already know that ferrofluid can make spikes when a magnetic field is applied. Now, watch what happens when I put a charged plate above these spikes. They actually shoot off tiny micro droplets of ferrofluid. You can't see the droplets flying off, but you can see it saturate this paper towel right above where each spike is. It works the same as or better than a needle, and you can manipulate the direction just by changing the magnetic field. This is so cool. The closer I move the electrode to it, the more it becomes a continuous stream. Even if I charge my fingers, it shoots up to my fingers. Look at those needle projections coming off each of them. Thank you. Oh, that is so weird. [Music] It looks like it's alive with like hair growing out of it. Now, the ferrofluid they use is a little different than I'm using here. Theirs is

an ionic liquid, as opposed to just an oil suspension that I have here. But if they can get this to work, it could be one of the coolest space propulsion techniques out there that has the ability to scale down very easily. So in the future, our skies could be filled with tiny satellites using ferrofluid propulsion. And thanks for watching another episode of the action lab. I hope you enjoyed it. If you did, don't forget to subscribe to my channel if you haven't yet. And you can also hit the Bell so that you get notified when I release my latest videos. And thanks for watching. We'll see you next time. [Music]

Ferrofluid Could Be The Future of Space Propulsion

The Action Lab is a channel dedicated to performing exciting experiments and answering questions you never thought to ask! I'll put things in my hydraulic press, vacuum chamber and perform countless other experiments just to watch cool phenomenon. I experiment on the world and objects around me. You'll be so amazed that you'll forget you are even learning anything! Please enjoy as I continually answer the "what would happen if..." questions you have. Feel free to comment with any scientific questions you have about anything. I have made my career as a PhD in Chemical Engineer and now I want to share how awesome science and experimentation can be! 

Visit my Facebook Page:
https://www.facebook.com/TheActionLabOfficial