M26
Open cluster in Scutum

10.1″ f/4.5, Mallincam DS432cTEC with 0.5 focal reducer and Astronomik UHC filter
Exposure = 5 sec, Live Stacked frames = 30, Gain = 41 of 250

M26 is a small compact cluster consisting of a couple dozen brighter stars of magnitude 9 to 12, measuring about 12 arcminutes across. The shape at the core is distinctly trapezoidal. Both O’Meara and Burnham Jr. report that there is a 2 to 3 arcminute “hole” at the center, inside the trapezoid, that has a couple of possible explanations: either it’s a dark nebula obscuring stars, or there are in fact less stars there – the question apparently has yet to be resolved.

M26 is 22 light years across and relatively distant for an open cluster at 5160 light years away.

North at 1 o’clock, East at 10 o’clock