Galaxy in Coma Berenices

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Messier 99 is a spiral galaxy with asymmetrical arms. One large arm extends to the right (west) in this image, and two smaller arms point to the left (east).

Messier 99 has the distinction of being only the second galaxy to have its spiral shape recognized (in 1846 by Britain's Lord Rosse, who also made the first observation of a spiral galaxy, Messier 51). Yet although Rosse was able to detect the spiral shape of these objects, neither he nor anyone else at the time knew what they were. It was not until the 1920s that these spirals were shown to be "island universes"--galaxies similar to our own Milky Way Galaxy, containing hundreds of billions of stars.

Magnitude 9.9
Apparent Size 5.4' x 4.7'
Distance (light yrs) 55 million
Right Ascension 12:18.8
Declination +14 25
Field of View 35' x 26'

Image details:  Exposure times of 60 minutes luminance and 30 minutes each of red, green and blue, taken with an SBIG ST-8300M imager and a 12" Meade telescope at f/5,6.

June 2013