The horizontal motion of a rising smoke occurs due to the horizontal motion of air relative to the object releasing the object. If the air is stationary relative to the object releasing the smoke, then the smoke will rise straight upward.
Flat-Earthers claim the motion of smoke rising straight up “proves” Earth is stationary. In reality, the horizontal motion of smoke is caused by the motion of surrounding air, relative to the object releasing the smoke, not the motion of the object itself.
Earth’s atmosphere is stationary relative to the surface. In other words, the atmosphere is rotating at the same speed as the rest of the Earth. Thus, we often see smoke rising straight upward if it is windless.
From the standpoint of a moving steam locomotive, the surrounding air is felt moving toward the back. Therefore, smoke emitted by the locomotive will move toward the back. Unlike Earth’s atmosphere, the surrounding air is not moving at the same speed as the steam locomotive.
- Smoke – Wikipedia