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How often are you overcome by a strong urge to levitate a frog? Your answer is most likely “not often.” However, this is just one of the many things science can achieve.

In addition to your frog, you’re going to need some magnets – the stronger the better. A magnetic coil of about 16 tesla should do the trick. Tesla is the unit used to measure how strong a magnetic field is. For reference, the Earth’s average magnetic field is a mere 0.00005 tesla. This means that you have a decently strong magnet on your hands. Apparently you can’t send these through NZ Post, so you’ll have to let me know how you got it. Now we’re ready to do some magnetic levitation!

Excitingly, magnetic levitation is exactly what it sounds like! It involves setting up magnetic fields so that objects can be suspended in mid-air. Suspending objects involves balancing forces that are trying to get the object to move in different directions. For example, the magnetic force your frog is experiencing is going to have to fight against the force of gravity.

Frogs don’t typically respond much when you hold a small magnet (like a fridge magnet) up to them. To see any action at all you need a magnet good enough to induce strong diamagnetism in a frog. Diamagnetism occurs when something creates its own magnetic field in the opposite direction, and in response to, an externally applied magnetic field. Then the two magnetic fields will repel each other. Usually this repulsion is not strong enough to be noticed, which is why you need such a strong magnet and why you can’t move frogs around with fridge magnets. If you are interested in who would actually attempt this, their names are Andre Geim and Michael Berry. They published a paper about it in the European Journal of Physics, titled “Of Flying Frogs and Levitrons.”

If you’re now thinking about levitating people, I regret to inform you that this hasn’t been achieved yet. Humans are heavier and so experience a greater gravitational force. A magnet strong enough to counteract this hasn’t been made. But magnetic levitation has applications beyond lifting frogs. You may have heard of incredibly fast maglev trains, which can reach speeds of up to 581 km/h. These use magnetism to accelerate the train in the desired direction. You might be feeling confused about why something as massive as a train can be propelled using magnetic levitation but you can’t (yet) levitate your best friend (or worst enemy). This is because the materials used to make these trains are more “magnetic” than a person is – they experience a greater magnetic force from a magnet of an equal strength. Another application can be found in what are called “magnetic bearings,” which use the principles of magnetic levitation to move parts of things like motors without physical contact.

Unfortunately, it is unlikely you will be levitating frogs or any other small animals anytime soon. Magnets strong enough to do this are expensive and you will need physics expertise to set up the magnetic field so that it is just right. But at least you now know you live in a world where this is possible. And that’s thanks to science, bitches!