Missing mass
Galaxies spin too fast for what we can see. This renders the mass we can't.
Placeholder study — replace with your own.
Input: published galaxy rotation-curve data — how fast stars orbit at each distance from the center, versus how fast they should orbit based on visible matter.
Process: Niagara particle galaxy driven by the real rotation speeds. The gap between observed and expected speed becomes a faint halo of dark particles, and a post-process pass bends the background stars around it like gravitational lensing.
What we noticed: the invisible part is most of the picture — the halo is several times bigger than the galaxy.