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Odds n Ends

      Messier 103
       Open Cluster in Cassiopeia
           RA:01h 33m 02s  Dec: +60 42' 00" Distance - ~9500 ly Size- 10.41 ly

Location & Date
Backyard, Abbott Observatory- Long Island, NY,  September 2022
TMB130SS  910mm F/7 APO, Moonlite focuser, Losmandy G11 Gemini
Image scale 1.54 arcsec/pixel
Baader LRGB  filters
CCD temp -10°C
L-12x3m  Red-12x3m  Green-12x3m  Blue-12x3m Bin 1x1
Planning & Acquisition
Sequence Generator Pro

CCDStack -  Calibration, Debloom
Astro Pixel Processor - LRGB Frame processing, RGB combine
Adobe PS -  L + RGB blend,  JPEG conversion
RC-Astro Star XTerminator & NoiseXTerminator


Messier 103 (also known as M103, or NGC 581) is an open cluster where a few hundred, mainly very faint, stars figure in Cassiopeia. It was discovered in 1781 by Charles Messier's friend and collaborator Pierre Méchain. It is located between 8,000 to 9,500 light-years from the Solar System and ranging over about 15 light years. It holds about 40 certain-member stars, two of which have magnitudes 10.5, and a 10.8 red giant, which is the brightest within the cluster. A bright known foreground object is the star Struve 131, not a member of the cluster. The cluster may have 172 stars if including those down to 50% probability of a gravitational tie. M103 is about 22 million years old.

Click on image for full size

Messier 103 position shown relative to our location (Sun) in the Milky Way Galaxy
Galatic Longitude: 128.1
Galatic Latitude: -4.31
Distance from Galatic Plane:169 ly below the galatic plane

Above image and info provided by Our Galaxy 3D Atlas application and used with permission by Otherwise