Messier 94, also known as NGC 4736 is a spiral galaxy in the constellation Canes Venatici. It was discovered by Pierre Méchain in 1781, and catalogued by Charles Messier 2 days later.
The structure of M94 is characterized by three rings, an inner one with a diameter of 70 arcseconds, an intermediate one with a diameter of 600 arcseconds, and finally a very faint outer one with a diameter of 15 arcminutes, which has turned out to be in fact, according to a very recent investigation, spiral arms with a very high star formation, even more than in the inner disk.
Acquisition details:
Baader Blue (CMOS-Optimized) 36 mm: 25×300,″(2h 5′)
Baader Green (CMOS-Optimized) 36 mm: 25×300,″(2h 5′)
Baader Red (CMOS-Optimized) 36 mm: 25×300,″(2h 5′)
Baader UV/IR CUT Luminance (CMOS Optimized) 36 mm: 60×300,″(5h)
Time of integration:
11h 15′
It is part of a small group of galaxies that also includes M 64 and Ngc 5023 and its distance is not known exactly but is between 15 and 33 million light years.
It is in the first one where a great star formation activity is concentrated, to the point that this galaxy is sometimes considered a starburst galaxy, being caused by the presence of a central oval structure similar to that of a bar that transports gas to the first ring. In addition, there is evidence of a past starburst in its center a billion years ago, and other authors also consider it as a galaxy with an already evolved starburst. The innermost regions of this galaxy, in fact, are considered the brightest among normal galaxies.
Link Astrobin: https://www.astrobin.com/6ifpd0/