Figure 19. NGC 4731, Type: E6, ρ = 0.5*tg(0.38*θ), Euler (18, 0, 0)

From

New Formulas and Mechanism for the Spiral Arm Formation of Galaxies

Hongjun Pan

International Journal of Physics. 2019, 7(3), 73-85 doi:10.12691/ijp-7-3-2