tycho crater: 3D!

on the moon, theres a large crater named tycho. it's the big one toward the southwest, with ejecta shooting out in every direction.


here's an amazing three dimensional video of its structure... here. 3D glasses: use 'em if you gottem! (the video is much much better in the high-res version).



the crater's shape is created from the impact of an object falling to the ground and splashing up material all around. you can sort of visualize the process from this excellent video of a water droplet falling into sand.



of course the structure of the sand after the impact quickly fades away, but you can still see the ring of material shot out in every direction and then one lingering mound of stuff right in the middle at the impact location.