This Messier object, also known as NGC 4736, is a magnitude 8.2 Seyfert spiral ring galaxy located 14 million light years away in the constellation of Canes Venatici at a declination of +41 degrees. This galaxy is the 16th brightest galaxy in the sky.
My image FOV does not cover the entire extended faint reaches of this galaxy.
My previous image of this object from 5 years ago shows the whole galaxy.
The bright blue starburst ring is the main feature of this beautiful object, with pink HII regions and blue star clouds. Note that this feature is not truly a continuous ring. It is more like the beginning arm structure of a barred spiral galaxy. The left starburst “arm” starts at 2 o’clock and extends counterclockwise to 8 o’clock, and the right one starts at 8 o’clock and extends counterclockwise to 2 o’clock.
Beyond the starburst ring, a diffuse disk extends out to about 35,000 light years. This outer region also contains a few isolated HII regions. Note that the main axis of this diffuse disk is not quite aligned with the axis of the starburst ring.
The dust lanes fascinate me. If you try to visually ignore the bright starburst ring, you will see that the dust lanes spiral continuously from core to outer diffuse disk edge. It surprises me that the dust lanes seem unaffected by the starburst ring. The dust lanes are much more visible at upper left, perhaps because that is the near side of the galaxy to us. The lower right side (far side?) may be obscured from our view by the faint galactic halo which likely exists above the galaxy disk.
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