A Cosmic Pinwheel

The journey through the constellation of Ursa Major (Big Dipper) takes us to a face-on galaxy located some 21 million light years away from Earth. Meet the Pinwheel Galaxy, which is catalogued as Messier 101 or M101. Messier 101 can be located by forming somewhat of an equilateral triangle to the south of the bright stars Alkaid and Mizar in the handle of the Big Dipper (see video). It was discovered by Pierre MΓ©chain in 1781, and has a relatively large magnitude in the night sky with a radius measuring around 85,000 lights across.

The rise of Ursa Major and M101

Gear: Omegon RC6, AA Hypercam 26c, iOptron HEM27, Svbony 120mm guide scope + ZWO ASI120mc.

Exif: 33 x 5-min lights; Gain 200, Offset 3, TEC @ 10 degrees; 20 darks, 20 flats, 20 dark flats

SharpCap, PHD2; AstroPixelProcessor, PixInsight; Photoshop


  1. Nice image of this amazing face-on spiral. I wish It appeared in my sky!

    I liked the video. Short and sweet but illustrating the motion of the stars.

  2. Very nice! There is your quintessential spiral galaxy in all it’s face-on glory!
    The music goes great with the video also! πŸ‘πŸ’―πŸ”­πŸ˜ƒπŸ˜Ž

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