M94 (NGC 4736)
M94 (NGC 4736) is an unusual spiral galaxy (type Sab) in
the constellation Canes Venatici. The bright
inner region of M94 is surrounded by a ring in which active star
formation is taking place as indicated by the presence of luminous,
blue clusters. Exterior to this is another, much fainter, ring comprised
of an older yellowish stellar population. In the outskirts, this region
ends again in a ring with moderate star formation activity, so that M94
is one of a relatively rare class of galaxies in which two waves of star
formation are evident. In long exposures, a further very faint ring, about
15 arc minutes across, can be seen. According to one theory, the outward
moving rings and bursts of star formation are generated by a rotating bar
of stars in the galaxy's nucleus.1
|M94. Image credit: NOAO/AURA/NSF
M94 was discovered by Pierre Méchain in
1781. It is part of the M94 group of galaxies, which is also known as the Canes Venatici I group.
||11' × 9'
||15 million light-years
(4.5 million pc)
||R.A. 12h 50m 53s,
Dec. +41° 07' 12"
||UGC 7996, PGC 43495
- C. Muñoz-Tuñón, N. Caon, J. Aguerri, L. Alfonso. "The Inner Ring of
NGC 4736: Star Formation on a Resonant Pattern." Astronomical Journal, 127, 58-74 (2004).