M91 = NGC4548 ( 12h 35.4m +14°30´, 10.2 mag. ) This large barred spiral galaxy in Virgo was discovered by Bode in 1774. Messier found "nebula without a star" above M90 on March 18, 1781 but wrote down inaccurate coordinates.
Located in the constellation of Coma Berenices is a small, dim galaxy known as M91. Until recently, this galaxy had been missing. Messier's notes had given the wrong position for this object.
M91 (NGC 4548) is another spiral galaxy, but is a rather confusing object, sometimes being labelled M58.
think they know what the Milky Way galaxy would look like from outside it. They have long thought that it is a spiral galaxy, like the Andromeda Galaxy or the Whirlpool Galaxy. However, recent research indicates it may be a barred spiral, like M91.
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