IC 2574 dwarf irregular galaxy in Ursa Major
Luminance 26 x 900 sec. + 12 x 600 sec. R, 15 X 600 sec. G, 15 x 600 sec. B all bin 1×1 (LRGB Baader filters) with FLI PL-6303e camera and CDK-12.5″
Guided with Orion AO at 6Hz. Fwhm aprox 2.2″~2.5″
All calibrated and processed with PixInsight 1.7. You can see the background filled with small galaxies, some near 25mag!
IC 2574 is commonly known as Coddington’s Nebula after the American astronomer Edwin Coddington, who discovered it in 1898. Astronomers classify IC 2574 as a dwarf irregular galaxy due to its relatively small size and lack of organisation or structure. These galaxies are thought to resemble some of the earliest that formed in the Universe. Dwarf irregular galaxies thus serve as useful “living fossils” for studying the evolution of more complex galaxy types such as our home, the Milky Way, with its central bar and spiral arms. The expanding shells in IC 2574 are of particular interest to astronomers as they reveal how supernova-driven explosions ignite round after round of star formation (Pasquali,Leroy et al.,2008 , Walter & Brinks,1999 , read more…).
Color composite of IC 2574 obtained with the LBT LBC Blue camera in the Bessel U (in blue), B (in green) and V (in red)
filters, during the Science Demonstration Time of February 2007. North is up and East to the left. The size of the image is 14’ × 11’, and
corresponds to the central one fourth of the LBC field of view. Pasquali,Leroy et al.,2008
A broadband photometric study of IC 2574 has indicated that 90% of its mass is in the form of dark matter, a figure in keeping with that of larger systems and with some other dwarf galaxies.
Contours image created with Aladin v.7 showing the boundary limits of the galaxy (aprox), and rotated North on top, East on left, coordinates J2000.
The constellation containing IC 2574 is Ursa Major (The Great Bear). IC 2574 is located about 12 million light-years away, belonging to the Messier 81 group of galaxies. This group is named after the most prominent galaxy in its midst, the big, bright and accordingly well-studied spiral galaxy Messier 81.Llegeix més "IC 2574"