Caption: This schematic diagram presents a hypothesis about the difference between star formation rate in ellipticals and spirals (FK-603).

It's probably true that this hypothesis is mostly wrong. It may be a true minority channel for the difference.

Nowadays, we believe most large ellipticals formed by galaxy mergers and that event somehow turned off star formation which caused galaxy quenching

Credit/Permission: © David Jeffery, 2003 / Own work.
Image link: Itself.
Local file: local link: galaxy_formation_wrong.html.
File: Galaxies file: galaxy_formation_wrong.html.