an open cluster in Perseus constellation. It is very large, having an apparent
diameter of 35’, and also bright, as it is visible also with naked eye under a
dark sky (the apparent magnitude is 5.5).
It is composed by at least 100 stars
and its estimated age is about 190 million years, so it is a very young clusters.
Its distance is 1500 light years.
In the image are visible many faint specks: they are in reality very far galaxies, and I was quite surprised to be able to catch them in spite of the very short total integration time
and poor quality of the sky due to severe light pollution.
Very near on the upper edge of the image is visible a small bluish disk: it is the planetary nebula PK144-15.1, also known as Abell 4.
Technical data Optic Tecnosky Apo refractor LT 130-910 with Riccardi reducer 0.75x (focal lenght 692mm, f/5.3)
Mount Skywatcher EQ8
Camera Atik 4000 with Starlight Xpress external filter
wheel 5 positions
Filters Baader 50mm
Guiding system Artesky Ultraguide 70mm
Exposure details R 20x300" bin1 -25C
G 20x300" bin1 -25C
B 20x300" bin1 -25C
Total integration 5h
Acquisition Voyager, PHD2
Processing Pixinsight 1.8,
Location Rescaldina (Italy), home terrace
Date 12/13 January 2021