This object is one of the most interesting galaxies in the entire sky, located only 13 million light years away in the southern constellation of Centaurus at a declination of -43 degrees. Its diameter is about 60,000 light years.
This is a bright (7.8 magnitude) and big (15 arc-minutes in apparent view) galaxy, but difficult for us in the northern hemisphere to see or image because of its southern declination and resulting low elevation in the sky. It peaks at about 16 degrees above the horizon for me. The distortion, poor seeing and poor tracking at this low elevation results in the soft stars and poor details that you see here, which are compensated for a bit by our excellent processing tools.
This galaxy is the 3rd
brightest galaxy in the entire sky. It has characteristics of both an elliptical galaxy (smooth, nearly featureless brightness profile) and a spiral galaxy (large bisecting dust lane), likely due to a collision and merger of two smaller galaxies.
This galaxy has a number of interesting and unique features. The elliptical nature of its broad shape is not spherical but is extended oblong in the axis perpendicular to its amazing dust lane. Unlike most galaxy dust lanes which appear 2-dimensional, this dust lane is clearly seen wrapping around the entire circumference of the galaxy and obscuring the bright core. This dust lane appears to overlap on the side of the galaxy facing us, where the dust band is twice as wide. Faint bluish star producing regions are seen along the edge of this dust lane, especially at the upper right and lower left.
One of its designated names, Centaurus A, is related to the fact that it is one of the closest and most prominent radio galaxies to Earth. The name dates back to the 1940s, when radio astronomy identified this galaxy as the strongest radio source ("A") within its constellation. The radio characteristics of galaxies such as this one are not seen in the visible spectrum.
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