Astronomy

Stars cross the spiral arms

Follow a marked star through a rotating spiral pattern. Move the corotation radius and see where the star overtakes the arms.

By Mykhailo Makarov

Actual application image

The model and its limits

Prescribed logarithmic density wave and circular test-star orbits with a flat rotation curve. Spiral-wave formation and self-gravity are not solved.

Equations used in the module

Equations
Ω(r)=v_c/r; φ_arm = ln(r/r₀)/tan i + Ω_p t; r_cor = v_c/Ω_p

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