This page contains a video of something every science student has imagined, but very few see: the demonstration that, in a vacuum, all objects fall at the same speed. Usually you learn of this demonstration and are left to imagine it, since setting it up is somewhat complicated. On rare occasions, this demonstration is actually carried out with an evacuated cylinder of glass containing a feather and a bullet or some other dense object. I’ve never seen such a demonstration, and I’ve certainly never seen it carried out on the scale documented in this video.

Related: how on Earth do they pump the air out of that chamber?