Balloon (aeronautics)

Type of aerostat that remains aloft due to its buoyancy

In aeronautics, a balloon is an unpowered aerostat, which remains aloft or floats due to its buoyancy. It may use hot air as a lifting gas, or it will use gas that is not air like hydrogen or helium. A balloon may be free, moving with the wind, or tethered to a fixed point.

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