What happens when you push a balloon full of air into a body of water, that's in space?
What happens when you push a balloon full of air into a body of water, that's in space?
My 8-year-old son asked this question and i couldn't give him a definite answer. So he's wondering if it would do the same thing as a balloon pushed underwater in the bathtub (which kind of makes sense to me, due to the density differences, not just gravity alone).
But I told him I'd ask those more knowledgeable than me.
The weight of the water compresses a balloon on earth.
In space, since everything is falling together, the balloon wouldn't compress, it would expand because the atmosphere and water isn't compressing it. The surface tension of the water would allow it to envelop the balloon, so long as there is enough water to allow it to do so, otherwise it would want to gather into a spheroid because there aren't enough large surface defects on a balloon to "hold" the water. If the surface of the balloon was covered in sand glued to it, just enough water would film across the surface of the balloon.
Water gathering on a rough surface means you could drown in space if you had a drinking tube leak into your helmet and you couldn't drink the water fast enough to breathe.
This assumes you have relatively normal air temperature and pressure.
Things change quite a bit if you interpret space to mean "open vacuum of space"
Then you have to decide if you mean orbit exposed to solar radiation, or interstellar exposed to galactic radiation. Or just in null gravity with null radiation.
This question can have a lot of answers depending on context.
Here is a video of an astronaut blowing air into a water bubble on the ISS. https://youtu.be/H_qPWZbxFl8?si=NLtNI9YPRUKHAeth
Link without site tracking: https://youtube.com/watch?v=H_qPWZbxFl8
Push a balloon under water and ignore what's happening in the vertical direction, just pay attention to how the two interact in the perpendicular to gravity plane.
The other answer is the balloon would pop and the water would evaporate but I'm assuming you mean just a 0 gravity environment and not a vacuum
There is a YouTube channel called Action Lab that asks and tests all kinds of questions like that. I don't know if this specific one was answered, but you and your son would probably enjoy a lot of the videos on there.