Reach For The Stars

Preceding the arrival of what is for many astronomers the highlight of the year, the Orion constellation and all it’s objects, is the appearance of the majestic Pleiades open star cluster (Messier 45) in the constellation of Taurus.  The so-called Seven Sisters consists of hot blue luminous stars that formed during the past 100 million years, which are expected to last another 250 million years and can be easily observed with the naked eye even here at Fairvale Observatory (Bortle 5/6).  

I have imaged this exciting star cluster before but with astrophotography and especially iconic objects such as the Pleiades, one is always drawn back for another try.  Now armed with Chroma filters and a growing list of PixInsight skills acquired since last imaged late in 2018, I wanted to tease out more details of the fine wispy dust cloud through which the Sisters are passing and forms the signature of all good Pleiades’ images.  Furthermore, with longer exposures and total integration time greater than before, maybe I could also capture something of the abundant interstellar dust that is present across the wider background?  

I am therefore very pleased that the final image (top of the page + cropped version above) which has more than achieved these objectives and marks a significant improvement on my previous attempts – it’s always worth trying that little bit more.

	IMAGING DETAILS
Object	M45 The Pleiades AKA Seven Sisters
Constellation	Taurus
Distance	444 light-years
Size	110’
Apparent Magnitude	+1.6
Scope	William Optics GT81 + Focal Reducer FL 382mm  f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 guide camera & PHD2 control
Camera	ZWO1600MM-Cool (mono)   CMOS sensor
	FOV 2.65o x 2.0o Resolution 2.05”/pix  Max. image size 4,656 x 3,520 pix
EFW	ZWO x8 EFW & Chroma 31mm LRGB filters
Capture & Processing	Astro Photography Tool + Deep Sky Stacker PixInsight v 1.8.8-11,  Photoshop CS3, Topaz AI Denoise
Image Location & Orientation	Centre: RA 03:47:03  DEC 24:03:08  Top = North   Right = West
Exposures	12 x 300 sec LRGB   Total time: 4 hours
	@ 139 Gain   21  Offset @ -20oC
Calibration	5 x 300 sec Darks  15 x Flats & Dark Flats LRGB    @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time	6th  December 2021 @ +19.15h
Weather & Moon	Approx. <=4oC      RH >=85%          🌙 New Moon