M37 - Open Star Cluster in Auriga


Copyright 2007 Hap Griffin

M37 is the brightest of three bright open star clusters in the constellation of Auriga (the others being M36 and M38).  Consisting of around 500 members, it is estimated that its age is approximately 300 million years judging by the fact that it contains a number of red giant stars, indicating a fairly long period of evolution.  M37 lies at a distance of 4400 light years.  


Date/Location:    December 17, 2007     Griffin/Hunter II Observatory    Bethune, SC
Instrument:    Canon 40D (modified IR filtering) Digital SLR through 10" Newtonian w/MPCC 
Focal Ratio:   f/ 4.7
Guiding:    SBIG ST-237 through Orion ED80
Conditions:    Cold and clear
Weather:    30 F
Exposure: 25 minutes total (50 x 30 seconds @ ISO 800)
Filters:    Baader UV/IR block internal to camera
Processing:    Focused and captured,  RAW to TIFF conversion, flat frame calibration, Digital Development, resizing and JPEG conversion in ImagesPlus.  Final tweaking in Photoshop CS2.