The moving image is a 3D-rendering of the Gaia DR1 star locations.
The image is interactive. With a mouse you can zoom in and out, pressing the left and right buttons.
On a phone or tablet, zoom by pinching, orbit with a one-finger swipe, and pan with a two-finger swipe.
With a keyboard you can zoom with the W and S keys, and pan with the arrow keys (or with A, D, F, and R).
Click "Open Controls" at the top of the image to display a menu to change the rotation speed or point size, and zoom in and out.