Liquid sand
Liquid sand iStock

Have you ever thought how it feels to swim in sand? If not, you don't seem to be the only one. But a NASA scientist decided to check what it would be like and managed to create a liquid sand that you can actually swim in.

It all began when Mark Rober, an NASA scientist, read in an old book that they'd managed to create liquid sand in the 1960s and 70s. Rober, like a real scientist, was curious to see how it felt - and went straight to try to create the sand himself. Although the old illustrations showed that thin pipes should be used to connect a gas balloon to a sandbox, they didn't show how to do it exactly. After dozens of failed attempts, Rober managed to connect the balloon correctly using thin pipes perforated with small holes at right angles at the tube's sides.

Rober explains that the gas prevents the sand grains from sticking to each other and creates a liquid surface that one can literally sink into. However, all this works only when the gas is connected; once the gas stops flowing into the sand - it immediately returns to its normal, solid state.

And how can liquid sand be used? There isn't really a clear answer. Apart from the pleasure of swimming in sand, one can envision creating a gigantic sand barrier that when infiltrators from neighboring countries try to pass it will start to flow and sink everyone into the sand.

So, the next time you're at the beach, remember that if you just plug in a gas balloon big enough under the sand - you might be able to sink all the sunglasses ice cream sellers into the sand. And if you have other uses for liquid sand - you're welcome to tell us in comments.