Why does a candle flame point up?
For grown-ups: the science
A candle flame points up because its hot air rises and carries the flame upward.
Combustion heats the surrounding gases, lowering their density relative to cooler air. In gravity, buoyancy drives the hot gases upward while cooler air flows in to replace them, creating a convection flow that elongates the flame. In microgravity, buoyant convection is greatly reduced and flames tend to be more spherical and can burn differently.
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Transcript
Look at a candle burning on a table. Why does its bright flame point up?
The flame heats the air around it. Warm air spreads out and becomes lighter than cooler air.
The lighter warm air rises, carrying glowing gases upward. Fresh, cooler air moves in from the sides.
This moving air makes the flame stretch toward the sky. Without gravity, a flame would look more like a round glow.
So a candle flame points up because hot air rises in gravity. The rising air gently pulls the flame along.