These are the two galaxies NGC4725 and its weaker neighbour NGC4712,situated far north (for Chilenian observers!) in the constellation of Coma Berenices.
Sized about 11 arcminutes,NGC4725 shines at a visual magnitude of about 10mag and so is an easily observable object even for smaller telescopes.
Classified as a SAB(r)ab-typed galaxy,it only has one spiral arm,in opposite to the normal case of posessing two or even more arms,as the other galaxxy NGC4712 shows.
NGC4725 lies about 50mio. light-years away.Some supernovas have been observed in the past: SN 1940B (type-IIP), SN 1969H (type-I), SN 1987E and SN 1999gs (type-Ia).
It was first seen by William Herschel in 1785.
position (epoch 2000):
RA.: 12h 50m 26,6s
Decl.: +25° 30′ 03″
image data:
LRGB image with L = 15x1200s, RGB = 6x1200s each,a total of 11.0 hours
80cm f/7 AstroOptik Keller corrected cassegrain FLI Proline 16803 Astrodon LRGB Gen-II filters
Prompt 7 CTIO/UNC Chile,remote controlled
image processing: Bernd Flach-Wilken
here you see NGC4725 to the left and NGC4712 to the right in a 22.2arcmin.-sized FOV.North is up.
To get full resolution: click here
here you have a more deatailed look to NGC4725 (filed-size 14´x14´)
with the Spitzer-IR-satellite you can see the brigt starburst-regions of this galaxy:click here