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M108 aka. NGC 3556
Magnitude: 10.7
Distance: Aprox: 45 million light-years
Constellation: Ursa Major
Diameter: 45.988 million light-years

Messier 108 is a barred spiral galaxy in the constellation Ursa Major. It was discovered by Pierre Méchain in 1781 or 1782. From the perspective of the Earth, this galaxy is seen almost edge-on.

This galaxy has an estimated mass of 125 billion times the mass of the Sun and includes about 290 ± 80 globular clusters. Examination of the distribution of neutral hydrogen in this galaxy shows shells of expanding gas extending for several kiloparsecs, known as H1 supershells. These may be driven by bursts of star formation activity, resulting in supernovae explosions. Alternatively they may result from an infall of gas from outside the galaxy or by radio jets.

Observations with the Chandra X-ray Observatory have identified 83 X-ray sources, including a source located at the nucleus. The brightest of these sources may be an intermediate-mass black hole that is accreting matter. The galaxy is also emitting a diffuse soft X-ray radiation within 10 kpc of the optical galaxy. The spectrum of the X-ray source at the core is consistent with an active galactic nucleus, but an examination with the Spitzer Space Telescope shows no indication of activity. The supermassive black hole at the core has an estimated mass equal to 24 million times the mass of the Sun.

Taken 2/18/18 in Chiefland Florida by Russell Kille on a CPC 1100 with Hyperstar @ F2 and ZWO ASI294MC Pro camera