Editing Openai/6945b8b5-5788-8000-9352-d5062c255aa0 (section)

=== Assistant: The conclusion doesn’t follow — the Earth can rotate and both flights can still take the same time. ===
The conclusion doesn’t follow — the Earth can rotate and both flights can still take the same time. The missing piece is the atmosphere.

Here’s the key clarification, cleanly:

===== - Eastward (counterclockwise from the North Pole). =====
* The surface, oceans and the atmosphere rotate together.

===== A plane is moving within the rotating atmosphere, not through empty space while the Earth spins underneath it. =====
* When a plane takes off, it already has the Earth’s eastward rotational velocity.
* London, Las Vegas, the runway, the air — all share that motion.

So there is no “catching up” to a moving Earth.

===== If: =====
* Wind conditions are similar
* Jet streams don’t strongly favor one direction
* Aircraft speed relative to air is similar

Then:
* London → Las Vegas ≈ Las Vegas → London

This does not imply no rotation — it means the reference frame is shared.

===== When flight times differ, it’s mainly because of: =====
* Jet streams (fast eastward winds) - West → East flights are often faster - East → West flights often slower

This difference is because the Earth rotates, shaping global wind patterns — not because the plane is chasing the ground.

===== : =====

If you want, I can explain this using:
* A moving train analogy
* Pure physics (reference frames)
* Or actual speed numbers (Earth rotation vs aircraft speed)