Barred spiral galaxy Messier 91 (M91) lies in the constellation of constellation of Coma Berenices. The galaxy’s bar stands out quite noticeably. The galaxy represents the faintest object in Charles Messier’s catalog, and he discovered it in 1781.
Notably, a rare error by Messier caused the galaxy to go “missing” for centuries, until amateur astronomer William C. Williams determined NGC 4548 (catalogued by William Herschel in 1784) was M91 in 1969.
Image obtained January-March 2014 by Adam Block and participants of the March 2014 “Astrophotography with Adam” courses.
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