Seven Glittering Sisters by Joe Bonner
Seven Glittering Sisters (Joe Bonner)

Seven Glittering Sisters by Joe Bonner

Photo of the Week for January 12, 2018 Of the many open clusters scattered across the celestial sphere, […]

Photo of the Week for January 12, 2018

Of the many open clusters scattered across the celestial sphere, few are as eye-catching as the Pleiades, also known as the Seven Sisters. Although the Pleiades are an obvious naked-eye sight, Charles Messier listed the cluster as M45 in his famous catalogue of non-comets. How could such a splendid collection of stars be mistaken for a comet? Consider a time when most comet discoveries were made without optical aid. Picture the Pleiades rising at dawn through a thick layer of atmospheric haze, and you can probably imagine how the cluster might be mistaken for a visitor from the cold, outer reaches of our solar system.

Seven Glittering Sisters by Joe Bonner
Seven Glittering Sisters (Joe Bonner)

This lovely portrait of the Seven Sisters was captured last September by Ottawa astrophotographer, Joe Bonner. He digitally stacked 17, 7-minute frames acquired with a Canon EOS 6D DSLR camera (set to ISO 800) and an Orion ED80 80mm, f/7.5 refractor telescope to produce the finished image.