When astronauts are out in space, their day is often filled with doing experiments, and conducting checks on their spacecraft. They do, however, have some time to play, and with zero gravity on hand, they can do some pretty cool things. In a new video released by NASA, a group of astronauts on the International Space Station (ISS) showcase the effects of zero gravity on liquids. The video has also been recorded using a RED 4K UHD camera.

The astronauts take a few millilitres of water, which in zero gravity, form a floating liquid ball. They then drop different coloured dye onto it, and it changes colour accordingly. This is followed up, most intriguingly of all, by an effervescent tablet, as we then see the liquid bubble fizz and move in the air. As such, it is probably the coolest way to take Cal-c-vita that we've ever seen.

Click on the video below and see how astronauts like to pass the time in space.