Is it a bird? Is it plane? No, it’s a…mouse?
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Scientists used to make mice float by making them smell cheese. Illustrated by Mike McRae |
Magicians are known to pull the occasional rabbit from a hat and make their assistant float high above the stage. But, do you want to know a secret? They’re all tricks! They rely on wires, trap doors and clever distractions. Researchers working for NASA have managed to weave a bit of magic themselves, using little more than the power of magnets.
If you’ve ever played with a magnet, you’d know it will stick to some things, like iron and nickel, but not to others, like copper, wood or your little sister’s head. However, scientists have long known that strong magnetic fields can still have an influence on other materials. In fact, magnetic resonance imagery (MRI) scans use the effect powerful magnets have on water to peek inside your body.
Water molecules are ‘diamagnetic’, meaning when inside a magnetic field, they create their own ‘opposite’ field, pushing them away from the magnet.
So if we’re made up of about 70 per cent water, and magnets can push around water molecules, it makes sense that we should be able to use them to make a person float off the ground. While it might be possible in the future, scientists have started with something a little bit smaller.
Several years ago, Dutch researchers used superconductors to create a magnetic field that lifted up a strawberry, a frog and a grasshopper. Now, researchers at the Jet Propulsion Laboratory in California have made an adult mouse float about inside its container.
Given they are mammals like us, making mice levitate could help us understand a bit more about the effect space travel has on our own bodies. In time, it might even prove to be a useful way of creating artificial gravity for astronauts.
Scientists are still yet to figure out how to make a rabbit appear spontaneously inside of a hat, however, which is good news for those magicians eagre to hold onto at least some of their best tricks.