The Pleiades, Messier 45, in Constellation Taurus

The Pleiades also known as the Seven Sisters, Messier 45, and other names by different cultures, is an asterism and an open star cluster containing middle-aged, hot B-type stars in the north-west of the constellation Taurus. At a distance of about 444 light years, it is among the nearest star clusters to Earth. It is the nearest Messier object to Earth, and is the most obvious cluster to the naked eye in the night sky.


Messier 45, the Pleiades, image data: f=430mm, f/3.3 50x180s Canon EOS 6Da ISO800

The cluster is dominated by hot blue luminous stars that have formed within the last 100 million years. Reflection nebulae around the brightest stars were once thought to be left over material from their formation, but are now considered likely to be an unrelated dust cloud in the interstellar medium through which the stars are currently passing. This dust cloud is estimated to be moving at a speed of approximately 18 km/s relative to the stars in the cluster.


Messier 45 with annotations

Exposure Data:
  • Telescope: Corrected Newton, f=430mm, f/3.3

  • Camera Canon EOS 60Da ISO800

  • Exposure Times
    • 50x180s

  • Total: 2h 30min

  • Date: 2024-01-10 Start about 20:35h UTC

  • Location: Bad Kreuznach / Germany

  • Mount Skywatcher EQ8R-pro / Pegasus Astro EQMod

  • Guiding and Exposure Control with INDI / PHD2 / CCDCiel running on XUbuntu Linux

  • Image Processing PixInsight and Darktable