M45 The Pleiades

M45. The Pleiades, Messier 45

M45 The Pleiades

Distance: 440 Light Years                            Telescope: Televue NP101

Magnitude: 1.6                                                Camera: QSI 683

Size:  110 Arc-minutes                                 Mount: AP 900

Age: Approx. 100 Million Years                 Exposures: L 20×600, R 20×600, G 20×600 B 20×600

M45, also known as the Pleiades, is a bright open cluster with reflection nebula in the constellation of Taurus. There are several hot and bright blue stars in the cluster along with about 1000 other stars and they are thought to be about 100 million years old. The reflection nebula was once thought to be gas remnants from the star formation but it is now thought that the cluster of stars is moving through space and happened to cross through a neighboring dust cloud on its current path towards the constellation of Orion. The evidence for this is that the star cluster is moving at a different speed than the dust which shows as the reflection nebula.

Also known as the Seven Sisters from Greek Mythology, this open cluster is easily seen with the naked eye and is similar in shape to the Big Dipper. The nine brightest stars which are commonly seen are Sterope, Merope, Electra, Maya, Taygeta, Alcyone, and Celaeno all of which are named for the Seven Sisters and are daughters of Atlas (father) and Pleione (mother) the other two brightest stars. There are a few nebulous regions around some of the stars. The Maia nebula, NGC 1432 surrounds the star Maia and consists of stringy, hair like nebulosity. In between Maia and Merope lays two fairly bright horizontal lines that almost appear like a scratch across the lens. It is thought that these streaky lines are shaped by the magnetic alignment of the dust particles in the area.  The Tempels nebula, NGC 1435 is below Merope and is slightly different in color from the rest of the area.

There is a small galaxy to the right of Electra that I have never noticed before. It is marked as PGC 13696 and I made an annotated image so you can see it here.

M45. The Pleiades, Messier 45

M45 Annotated

2 Responses to M45 The Pleiades

  • Hi John,
    Sorry it has taken me until now to get back to you and thank you for a great day spent with you and Larry. The tutoring was excellent and again I thank you. I was going through your photos of your equipment out at Anza I believe. Question- Do you ever bring the AP900 to the desert or is that permanent at home. I have the same NP101 and QSI 683 and love them to death. My next purchase will be a Paramount MX+ but it will be a while. Need to win the lottery. Again thanks for the good time and a great web site.


    • Hi Dick, I love the NP101 and QSI683 combo. You should also try the Televue .8 reducer for this scope as it gets you to F4.3 at 432mm FL. This is a great combo for wide field imaging.

      I do bring the AP900 to the desert and it is actually easier to move than my old CGEM or G11. The heads for these two mounts are one piece but the AP900 mount can be easily disassembled in two pieces with two knobs.

      Let me know if you are ever out this way again.


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