There’s no need to look up to see the clouds in the sky when you can make a fun cloud of your own at home! Try this easy experiment to create a cloud in a bottle. The few supplies you will need are a two-litre transparent plastic bottle (with label removed), matches, and water.

The first step is to pour hot water into the bottle. You can use hot tap water, but not boiling water, as this might warp the plastic and the experiment will not work. The water should be about 60˚C.

Pour enough water to cover the bottom of the bottle by about two centimetres. Swirl the water around to warm up the sides of the bottle.

The next step is to strike a match, and blow it out after a few seconds. Make sure an adult is performing this step. Tilt the bottle with one hand and insert the head of the match into the top of the bottle. Do not throw the match into the bottle. Let the smoke from the match fill the bottle, and then discard the match. At this point, quickly screw the cap back on the bottle.

The last step is to squeeze the sides of the bottle hard. Do this three or four times. Wait a few seconds then squeeze the bottle again, this time holding the squeeze longer before releasing. You should see your very own cloud there!

So how does all this work? Putting pressure on the bottle’s sides forces the water particles to compress. Letting go of the sides causes air to expand, decreasing the temperature. When air cools, particles stick together more easily, causing clumps to form into tiny droplets around the smoke molecules, similarly to how clouds form in the sky.

For other variations on making clouds, visit www.wikihow.com/Make-a-Cloud-in-a-Bottle.