star or galaxy
Is this a star or a galaxy? How can I differentiate between star and galaxy.
by Budgieye moderator
Sometimes, it can be hard to tell.
Stars are round, are the same colour throughout its disk, and have edges, even if the edges are fuzzy. They can be red, bright orange, greenish, and blue.
Elliptical galaxies are oval with a small bright nucleus. They are often different shades of colour, white and yellow, yellow and orange or orange and red in our images. An elliptical viewed edgeon can be difficult to distinguish from a star.
For some images, see Alice and the Ellipticals, Galaxy Zoo to the Rescue! (Wed 26 Jun '13) http://talk.galaxyzoo.org/#/boards/BGZ0000001/discussions/DGZ00002kk