Elliptical Galaxy Simulator

Elliptical galaxies are among the oldest and most massive structures in the universe: smooth, featureless spheroids of old stars with almost none of the gas and dust that fuels new star formation in spirals. This simulator builds one from thousands of individually colored stars distributed on a centrally concentrated radial profile, then lets you reshape it — flatten it from a near-round E0 into an elongated E7, dial in the simplified v ∝ r rotation law that mergers are thought to leave behind, and shift the mix between old red Population II stars and the rarer young blue ones. Orbit the camera to see how ellipticity and rotation together produce the uniform, structureless light distribution that sets ellipticals apart from spiral galaxies.