Galaxies that can't be classified as either spiral or elliptical are called irregular galaxies. Every irregular galaxy is unique. It doesn't look like any other galaxy. It just isn't a spiral or an elliptical.
Irr I galaxies have lots of young stars, gas, and dust, but do not have spiral arms.
Irr II galaxies look strange. It seems likely that Irr II galaxies have been distorted by collisions with other galxies at some time in their history.
South of the Equator, it is possible to see the Large and Small Magellanic Clouds, the two irregular galaxies closest to our own Milkey Way Galaxy. Astronomers predict that they will eventually collide with the Milkey Way and be incorporated into our own galaxy.
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