There are three main types of galaxies: Elliptical, Spiral, and Irregular. Two of these three types are further divided and classified into a system that is now known the tuning fork diagram.Apr 18, 2000
Astronomer Edwin Hubble classified galaxies into four major types: spiral, barred spiral, elliptical and irregular. Most of the nearby, bright galaxies are spirals, barred spirals or ellipticals. Spiral galaxies have a bulge at the center and a flattened disk containing spiral arms.
This material will interact when the galaxies collide. ... There is also friction between the gas in the colliding galaxies, causing shock waves that can trigger some star formation in the galaxies. These processes can radically affect the galaxies. For example, two spiral galaxies can merge to form an elliptical galaxy.Jun 27, 2015