system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Gases in space, do they form little spheres like tiny planets or move like earth clouds. How do they keep themselves together?
gpt
The short answer is gravity. Gravity exists between any two objects but it is weak unless there is a lot of mass. In the absence of any other forces a gas, or any other material for that matter, will form a sphere because of those gravitational forces.

If the cloud is small enough it will be subject to other forces and won't be really spherical, but with enough size it will keep its shape more. Jupiter would be a good example of that.