Russell Croman Astrophotography  



Galaxy Cluster Abell 194

About This Photograph

Abell 194 is a cluster of galaxies in the constellation of Cetus. It consists of over 100 members at a distance of approximately 265 million light years. This is roughly the same distance to another galaxy cluster, the Perseus Cluster.

The brightest members of Abell 194 appear in the upper right of the photograph. The close pair in the extreme upper right are designated NGC 547 (upper) and NGC 545 (lower). Below and to the left of these is the rather round elliptical galaxy, NGC 541. Note the common "envelope" of hot gas surrounding these three, clearly indicating that they are gravitationally interacting.

The small blue object to the upper right of NGC 541 is called "Minkowski's object," an irregular dwarf galaxy with an unusually high rate of star formation. Dwarf galaxies usually consist of older, yellow stars with very few blue (young) stars. The current theory of Minkowski's object is that it is being blasted by a jet of hot gas from the nearby NGC 541, triggering the burst of star formation observed.


Technical Details

Optics:20" f/8 RCOS Ritchey-Chr├ętien Cassegrain w/ RCOS Field Corrector
Camera:SBIG STL-11000M, FLI CFW-7
Mount:Software Bisque Paramount ME
Filters:SBIG Standard LRGB
Dates/Times:21-27 November 2005
Location:Dimension Point Observatory, Mayhill, New Mexico
Exposure Details:LRGB = 480:180:75:180 minutes
Acquisition:MaxIm DL/CCD 4, TheSky6, CCDAutoPilot2
Processing:CCDStack, Photoshop CS2, GradientXTerminator