Question

There is no gravity in space right..? Then how could neilarm strong put his keg on the moon...

Answer 1

no your ouestion is wrong gravity is every where in the space.and what do you mean by space you must know that space is evry where around you

Answer 2

The astronaut had to wiggle the flag pole to get it set into the ground properly.  That wiggle induced a wave in the flag, that without an atmosphere to dampen it, continued for quite a while.

There are also folds in the flag that are caused by the telescoping mechanism that ran along the top of the flag to keep it vertical. (Incidentally, the flag is a regular nylon flag ordered from a government supply company).

Put the two together and it looks like it is flapping.