Why did the flag wave on the moon?


Why did the flag wave on the moon?

In: Physics

The action of planting the flag gave it movement. The pole wasn’t just a pole but also had a horizontal bar to hold the flag outstreched.

Mythbusters had a bit on it where they made a scale model of the flag for the moon landing and moved it in a vacuum chamber to see if the flag would move the same way it does in the moon landing footage

They spun the flag while planting it. That gives initial angular momentum for the flag. When they stopped doing it, the the horizontal bar that hold the flag stopped. The flag, however, continued to move due to its inertia, resulting in a wavy motion. On Earth this also happens, but the motion quickly dies out due to large air drag. Since there is no air on the moon, the motion lasts much longer.

So there are a couple of points as why the flag “waves” on the moon and some misunderstandings as well. I’m on mobile so please excuse any formatting issues etc.

1) there is a vertical pole for the flag, as per normal. But also a horizontal one as well that displays the stars and stripes clearly. If there was no horizontal pole then the flag would just hang down by the vertical one, not very clearly the flag of the USA and it would not look as good. The horizontal pole shows the stars and strips in all its glory.

2). In putting up the flag and the poles movement was imparted onto the flag causing the flag to move. The flag is actually moving at this point.

3) as the flag is in a vacuum there is no damping effect of he air slowing down its movement so the flag moves after being touched, as described in 2, for a lot longer than one would expect.

It didn’t wave. It had an arm which held it out. The ripples in the flag were wrinkles. It did move when the astronauts took off from the moon due to the rocket exhaust. Buzz Aldrin said it got knocked over. Later landings planted it further away.