Can you blow bubbles in space?
Bubbles are pretty neat, aren't they? You can blow bubbles from a special little wand and watch them float around in the air until... *POP* ...they're gone! What happened?
When you blow a bubble, you are pushing air onto the bubble's soapy surface. The pushing of air in scientific terms is known as 'pressure.' Near the surface of the Earth, there are a lot of air molecules pushing on each other. So the pressure near the surface is high. As you go higher in the atmosphere, there are less and less air molecules, so the pressure gets lower.
When you blow a bubble, you are exerting a high amount of pressure into the bubble. The bubble is being pushed on the inside by air from your breath, but is also being pushed on the outside by air in the atmosphere. When the bubble leaves the wand, the air inside the bubble has the same amount of pressure as the air outside the bubble.
The bubble may float for a while, as the air outside the bubble tries to stay the same as the air inside. Eventually, however, the bubble will pop. If the bubble floats too high in the atmosphere, the pressure inside the bubble will become too great, and the bubble will explode in a big *POP*. If the bubble sinks too close to the ground. The pressure inside the bubble becomes lower than the pressure outside and the bubble will implode. We still hear it as a *POP*.
In space, there is no pressure. There are no air molecules in space to
push anything. So if you try to
blow a bubble in space nothing will happen. The air molecules inside the
bubble have nothing to push against so the bubble
will pop before it starts to form. The bubble can only exist when there
is equal pressure inside and out.
Submitted by Will (age 18, Kentucky, USA)
(November 3, 1997)