What is the main difference between elliptical galaxies and spiral galaxies

like our own galaxy, fall into several classes depending on their shape and the relative size of the bulge: ordinary spirals are labelled either Sa-d,m while those which have developed a bar in the interior region of the spiral arms are SBa-d,m. Spiral galaxies are characterized by the presence of gas in the disk which means star formation remains active at the present time, hence the younger population of stars. Spirals are usually found in the low density galactic field where their delicate shape can avoid disruption by tidal forces from neighbouring galaxies.

are placed in the categories E0-7 depending on their degree of ellipticity. They have a uniform luminosity and are similar to the bulge in a spiral galaxy, but with no disk. The stars are old and there is no gas present. Ellipticals are usually found in the high density field, at the centre of clusters.

this is what i have found online, hope i helped :)

c. is the correct answer

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