Inspect a stellar disk, central bulge and transparent halo while tracer stars rotate at radius-dependent angular speeds. A radial probe connects the 3D structure to a rotation curve. Vary luminous mass and halo strength to compare their contributions.
• A real-time 3D scene with 5 inspectable parts (Stellar disk, Central stellar bulge, Extended halo, Radial measurement probe, Rotation-curve comparison), with home view, focus-selected-part, auto-rotate, expand, instrument-cover and hide-labels scene tools, plus a model response curve beneath the scene. • Experiment controls: Bulge mass (0.1-3 10¹⁰ solar masses); Disk mass (1-12 10¹⁰ solar masses); Halo asymptotic speed (0-260 km/s); Halo core radius (1-8 kpc); Probe radius (0.5-25 kpc); Million years per animation second (1-60 Myr/s); pause/resume, 0.1 s and 1 s single-step buttons, four playback speeds and a restart button. • Live readouts: Probe radius; Total circular speed; Luminous-only speed; Halo contribution; Probe orbital period; Elapsed model time. • A Geometry & measurements tab with a parameter-comparison chart, a live-measurements chart, the model equations and snapshot readouts. • An Experiments tab with 3 guided presets (No halo; Strong extended halo; Large core) and a Model verification bench that runs independent fresh models, plus a timestamped event log and a copyable trial report. • A Learn & assess tab with guided lessons, a knowledge-check quiz with reset and a written model-scope statement linking to a technical reference.
G=4.30091×10^-6 kpc(km/s)²/M☉ vbulge²=GMb r/(r+0.7)² vdisk²=GMd r²/(r²+3²)^(3/2) (Kuzmin disk midplane) vhalo²=v0² r²/(r²+rc²) vtotal²=Σvi²; period=2πr/v ×977.792 Myr
Axisymmetric circular test-particle dynamics in analytic bulge, thin-disk and halo potentials. Initial spiral placement is a visual tracer pattern, not self-consistent spiral density waves. No star formation, gas hydrodynamics, collisions, central black-hole dynamics or fit to a specific galaxy. Halo surface is illustrative; logarithmic halo is not truncated in the model.
No. Squared speeds add because radial gravitational accelerations add.
No. It is a visual guide to an assumed gravitational component.
Axisymmetric circular test-particle dynamics in analytic bulge, thin-disk and halo potentials. Initial spiral placement is a visual tracer pattern, not self-consistent spiral density waves. No star formation, gas hydrodynamics, collisions, central black-hole dynamics or fit to a specific galaxy. Halo surface is illustrative; logarithmic halo is not truncated in the model.