M91 (NGC 4548) is a barred spiral galaxy located within the constellation Coma Berenices in the Virgo Cluster of galaxies.
M91 is best viewed during late spring, is magnitude 11.5*, and can be viewed with small telescope. It is 5.4 x 4.4' in size. For reference, the full moon is 30' (arc minutes) in size.
* The naked eye can see up to magnitude 8 objects under ideal dark sky conditions.
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