Russell Croman Astrophotography  



Spiral Galaxy M74

About This Photograph

M74 is often cited as a prototypical "grand design" spiral galaxy. Winding out from the central core of older yellow suns, its graceful arms trace the wave of formation of new stars in the disk of the galaxy. The magenta patches are clouds of energized gas where new stars are just being born, similar to our own galaxy's Orion Nebula. Once they dissipate, these clouds leave behind bluish clusters of hot, young stars, also visible in this photograph.

Apparently spiral arms such as these are transient phenomena, and do not rotate along with the rest of the material in the galaxy's disk. Rather, they are compression waves traveling through the disk, triggering star formation as they propagate.


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:4-27 October 2005
Location:Dimension Point Observatory, Mayhill, New Mexico
Exposure Details:LRGB = 270:210:85:150 minutes
Acquisition:MaxIm DL/CCD 4, TheSky6, CCDAutoPilot2
Processing:MaxIm DL/CCD 4, Photoshop CS2, GradientXTerminator