Probably the most well known and easiest to recognize asterism in the northern hemisphere.Most people will at least have heard the name big dipper,and there is no ambiguity about the name and the appearance of this one. Stars from left to right are Dubhe, Merak, Phekda or Phad, Megrez, Alioth, Mizar/Alcor(the horse and rider), and Alkaid. Interestingly they do seem to be a real star cluster, moving in the same general direction and at about 75 light years away from us.Unlike most other constellations which are just chance alignment. Dubhe and Merak are useful as they point the way north to Polaris the North star.
Image Data
Optics: Tamron 17-50mm f/2.8 set at 35mm f/2.8
Camera: Canon EOS X5 DSLR (unmodified)
Mount: Fixed Tripod
Exposure: 25 X 5seconds at ISO 1600 RAW
Calibration: Stacking,Flats,and Bias in DeepSkyStacker by Luc Coiffier
Processing: Gradient removal in Iris by Christian Buil, levels, curves, color in PS
Location: Quezon City, Philippines
Date Time: February 21, 2012. 11:00-11:03pm PHT
Conditions: 28C, 80RH, cloudless clear sky
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