M45 - The Pleiades Cluster

The Pleiades, also known as the "Seven Sisters", is the most famous of all star clusters in the night sky. This cluster, which is an easy naked eye object even under urban skies, is located approximately 375 light years from Earth and is estimated to be 100 million years old. Visible in this image is the blue reflection nebula which is associated with the brighter members of the cluster. This nebulosity can be detected visually under good conditions. This star cluster also serves as a test for visual acuity and observing conditions. The test involves determining the number of Pleiads visible to the naked eye. Most observers under reasonably good conditions can identify at least six, while those with extremely good eyesight have claimed to identify up to 16.

Image Specifications:

     •  Instrument:  Canon EF 200mm f/2.8L @ f3.5
     •  Camera:  Canon 20Da
     •  Filters:  Hutech IDAS LPS (Light Pollution)
     •  Mount:  Losmandy GM-8 Equatorial
     •  Guiding:  SBIG STV Autoguider with Vixen 400mm Guidescope
     •  Time / Date :  November 24, 2006, 9:00PM EDT
     •  Location:  Coyle Field, NJ
     •  Weather:  Clear, 40degF
     •  Primary Exposure :  9 x 90sec, ISO 1600, RAW, average combined
     •  Calibration Frames:  15 x 90sec, ISO 1600, RAW, average combined
     •  Image Processing :  Images Plus, PixInsightLE, Photoshop CS2, NoiseNinja