Changes

==Environment and Structure==

==Environment and Structure==

The Whirlpool galaxy has a diameter of 60,000 [[light year]]s and an estimated mass of 160 billion solar masses.<ref>[https://www.nasa.gov/multimedia/imagegallery/image_feature_2457.html The Whirlpool galaxy] from nasa.gov</ref><ref name=constellation-guide/> This is around 35% the size of the [[Milky Way]]. The distance across both galaxies is about 75,000 light years. The smaller galaxy, NGC 5195 is a dwarf galaxy and classified as an [[irregular galaxy]].

The Whirlpool galaxy has a diameter of 60,000 [[light year]]s and an estimated mass of 160 billion solar masses.<ref name=constellation-guide/><ref>[https://www.nasa.gov/multimedia/imagegallery/image_feature_2457.html The Whirlpool galaxy] from nasa.gov</ref> This is around 35% the size of the [[Milky Way]]. The distance across both galaxies is about 75,000 light years. The smaller galaxy, NGC 5195 is a dwarf galaxy and classified as an [[irregular galaxy]].

The galaxy is believed to have a supermassive [[black hole]] at its centre. The galactic core is fairly active, meaning it is a Seyfert galaxy spcefically, type 2.5.<ref>[http://space-facts.com/whirlpool-galaxy/ Whirlpool galaxy] from space.com</ref><ref>[http://www.messier.seds.org/m/m051.html M51] from messier.seds.org</ref>

The galaxy is believed to have a supermassive [[black hole]] at its centre. The galactic core is fairly active, meaning it is a Seyfert galaxy spcefically, type 2.5.<ref>[http://space-facts.com/whirlpool-galaxy/ Whirlpool galaxy] from space.com</ref><ref>[http://www.messier.seds.org/m/m051.html M51] from messier.seds.org</ref>