sentence: Luminosity diminishes  with distance from the centre.
sentences_before: Unlike a disk-shaped spiral galaxy, Messier 87 has no distinctive dust lanes. It has an almost featureless, ellipsoidal shape.
sentences_after: At the core is a supermassive black hole. This is a strong source of multiwavelength radiation, particularly radio waves.
concept_name: luminosity
headings: Messier 87
categories: Elliptical galaxies