And those gases have weights, they have, formally, atomic weights, just like the Nitrogen Oxygen atmosphere does.

Standard air air resists gravity when heated. It's why you can feel the strong vertical component to rising air over a car hood or a barbecue pit.

It's a matter of relative energies of the very same gas molecules and the effect lasts until energy levels drop, then it falls back to the surface, pulled down by gravity.

That's why fire tends to have a pronounced vertical streamer effect.

Standard air components don't escape the downward force of gravity at the energy level we're receiving from the sun.

That's why they're the standard components, and hydrogen and helium aren't.

Their differing

atomic

weights.

At typical energy levels here on Earth.

And those gases have weights, they have, formally, atomic weights, just like the Nitrogen Oxygen atmosphere does.

Standard air air resists gravity when heated. It's why you can feel the strong vertical component to rising air over a car hood or a barbecue pit.

It's a matter of relative energies of the very same gas molecules and the effect lasts until energy levels drop, then it falls back to the surface, pulled down by gravity.

That's why fire tends to have a pronounced vertical streamer effect.

Standard air components don't escape the downward force of gravity at the energy level we're receiving from the sun.

That's why they're the standard components and hydrogen and helium aren't.