M-45 (MELOTTE 22) commonly called the Pleiades or The Seven Sisters, is a bright, nake-eye star cluster located in the constellation of Taurus, the Bull. It is one of the nearest of star clusters to Earth, being only 440 light years distant. The cluster is dominated by hot, luminous blue-white stars that have formed within the last 100 million years. The reflection nebulosity surrounding the brightest stars in the cluster was one considered to be left over gas from their formation, but is now known to be an unrelated cloud of dust through which these stars are currently passing. Charles Messier measured the position of the cluster and included it as number 45 in his catalog of comet-like objects published in 1771. The cluster is 8 light years in diameter.
This image, acquired on December 18, 2017, is a 1 hour integration of 6 minute exposures through the Celestron C-11 at f/2, using the HyperStar III imaging system and the ZWO ASI 071MC color CMOS camera, operating at -10 degrees below ambient temperature and binned 1 X 1. Guided, captured and combined using Maxim DL5 Pro. Post processed using PhotoShop CS2, Gradient XTerminator, StarShrink, Carboni's Astro Tools, and NoiseWare.