Helium symbol = He
If I’m holding a helium balloon in outer-space high above our Earth’s atmosphere which way will the He-balloon float?
Like all things helium gas obeys the laws of Earth’s physics, fresh water rises over salt water so will gases depending on their densities, He-gas will rise above Ozone but remain stationed below Hydrogen and as all of Earth’s gases layer themselves one over the other from the bottom up there comes a limit to where there will be a clear separation between the layers of these gases (atmosphere) and the void of space. And this limit does exit or we would lose all of Earth’s gases including our oxygen to the vast emptiness of space, so, these gases do respect the laws of Earth’s physics. This is how the Shuttle after plunging through the atmosphere falls back and hovers over the Earth and needs rocket engines to help break-thru the first layers of these gases until inside this invisible dome then shuts off the engines and glides to the surface of Earth.
Question remains, which way will this helium balloon float?