'''[[File:AXgxzl.jpg|thumb|left|358px|An example of a spiral galaxy.]]Galaxies '''are enormous groups of stars, stellar remnants, dust and other structures. Not counting galaxy clusters and other large-scale cosmic structures, galaxies are the largest and most massive objects in the Universe, ranging from just a few hundred parsecs in diameter for the smallest and 100 kiloparsecs for the largest.
'''Galaxies '''are enormous groups of stars, stellar remnants, dust and other structures. Not counting galaxy clusters and other large-scale cosmic structures, galaxies are the largest and most massive objects in the Universe, ranging from just a few hundred parsecs in diameter for the smallest and 100 kiloparsecs for the largest.
Probably the most important parameter of a galaxy is it's type. Spiral and barred spiral galaxies appear to be the most common type of galaxy, elliptical galaxies coming in as a close second and irregular galaxies being the most uncommon. This classification determines the stellar composition of the galaxy, as well as the frequency of some types of nebulae and clusters.
Probably the most important parameter of a galaxy is it's type. Spiral and barred spiral galaxies appear to be the most common type of galaxy, elliptical galaxies coming in as a close second and irregular galaxies being the most uncommon. This classification determines the stellar composition of the galaxy, as well as the frequency of some types of nebulae and clusters.
Revision as of 03:49, 9 December 2015
An example of a spiral galaxy.
Galaxies
Galaxies are enormous groups of stars, stellar remnants, dust and other structures. Not counting galaxy clusters and other large-scale cosmic structures, galaxies are the largest and most massive objects in the Universe, ranging from just a few hundred parsecs in diameter for the smallest and 100 kiloparsecs for the largest.
Probably the most important parameter of a galaxy is it's type. Spiral and barred spiral galaxies appear to be the most common type of galaxy, elliptical galaxies coming in as a close second and irregular galaxies being the most uncommon. This classification determines the stellar composition of the galaxy, as well as the frequency of some types of nebulae and clusters.
