Supermassive black hole at the center of the Milky Way.
Mass ≈ 4×106 M☉ · Distance ≈ 27,000 ly
What this approximates: a real-time artistic view of a thin accretion disk with spiral structure, approximate gravitational lensing of the starfield, a photon-ring–like glow, and soft bloom. Not a general-relativity geodesic integrator or an Event Horizon Telescope reconstruction.
Works in desktop and mobile browsers with WebGL. Lower Quality reduces star detail and bloom for weaker GPUs.