Eli5: How come fire flames go upwards and why do the flames always “dance” around?

Question

Eli5: How come fire flames go upwards and why do the flames always “dance” around?

In: 285

Answer 1

They go up because hot gas is lighter than air, and therefore rises. For comparison, on a space station, flame doesn’t go up, it forms a sphere.

They “dance” because the burning is irregular, plus the moving particles cause turbulence. For comparison, a gas flame is very regular and barely “dances” at all.