Category: Star Clusters

Open & Globular Star Clusters

Globular Star Cluster M13 (NGC 6205)

M13 Globular Star Cluster in Hercules NGC 6205 TEC140 f/7 Canon 20d
Telescope / Lens TEC 140 f/7 980mm; TMB 80 f/6 manual guiding
Mount Type Astro-Physics 1200 mount
Camera Canon 20D & Angle C magnifier
 Filters N/A
 Film  Digital
 Exposure 5 minutes x 8 stacked
 Processing Photoshop CS2 Cropped; 2017 CS6 & CCDStack
 Date  9-11-2007
 Location June Mountain, South of Eagles Rest, Oregon
 Conditions 3232′ magnitude 6.2 Skies; Clear & Steady

The brightest globular cluster in the northern latitudes, the Globular Star Cluster in Hercules M13 (NGC 6205) shines at magnitude 5.8 and is visible to the naked eye from a dark sky site. It is approximately 20 arc-minutes in diameter with around 300,000 stars. Located in western edge of the Keystone in the constellation of Hercules. It takes an 11-12″ telescope to resolve the stars decently, like diamond dust on black velvet. Go to a 14″ or larger at a dark sky site and it is a real treasure! The Great Hercules Globular Cluster of stars lies 22,200 light years from earth. This is roughly one quarter the width of our Milky Way Galaxy.

The larger galaxy, upper right-hand corner is NGC 6207 at magnitude 12.2 , 3 x 1.2 arc-minutes and 45 million Light years distant, about the distance of the Virgo Galaxy Group . The smaller galaxy, just to the upper right of the globular cluster, in between M13 and NGC 6207. This galaxy is IC 4617 magnitude 15.5, 1.2′ x 22″, at 489 million light years away.  A visually challenging object through an eyepiece.

DSLR (Digital Single Lens Reflex)  cameras are really opening new doors in astrophotography and the Canon 20d and 20da really preform. Currently in 2018, the Canon 6d (full size) and 7d Mark II (APS) have really made monumental strides in Resolution, QE (Quantum Efficiency), Noise, etc.

New M13 Image 8/14/2022

M13 Globular Star Cluster
4/16/2021 1:22 AM PST Latitude: 33° 29′ 01.48″ North Longitude: 116° 43′ 19.24″ West Elevation: 4321 ft. Jupiter Ridge #4 Observatory; OCA site, near Anza, CA.

Additional data from imaging with TEC 140 f/4.55 f 637mm (APEX-L) SQM: 20.85. Telescopes / Optics: TEC 140mm f/4.55 RGB= 3 x 5 minute; L= 10x x 5 minute -20°c. Total LRGB= 95 minutes. This data was added to existing DSLR & CCD data to go deeper and improve resolution. FWHM: 1.56 average. Processed with CCDStack, Photoshop CS6, Pixel-Insight. Final image has approximately 3.5 hours of data. Several background galaxies are clearly visible.

The Pleiades Open Star Cluster M45

Pleiades Open Star Cluster M45
Pleiades Open Star Cluster M45 also know as Maia Nebula
Telescope / Lens300mm f/2.8  Lens;  420mm f/4 Lens DSLR
Mount TypePiggyback on G11 (Stepper)
CameraCanon F-1 ; Canon 20D
 Filters112mm UV
 Film Kodak E200 (Slide Film)  DSLR
 Exposure2 film exposures 45 min. ea; manual guiding FS/78; 10 DSLR
 ProcessingSlides scanned Nikon 5000 @ 4000dpi 16bit (130 MB files) 3 images stacked; processed in Photoshop CS5 AIP & CCDStack DSLR images stacked with film in CCDStack
 Date 7/25/2003 & 8/20/2004
 Location Oregon Star Party 120° 09′ W 44° 18′ N
Indian Trail Springs, Ochoco National Forest (Also Eagles Rest 25 miles SE of Dexter, Or.)
 Conditions5000′ magnitude 6.2 Skies; Clear & Steady

The Pleiades M45, is a well known naked eye Open Star Cluster in the constellation of Taurus (The Bull). The Pleiades (M45) is a young open cluster of stars enshrouded in gas and dust which is illuminated by several bright stars. Also know as the Seven Sisters covering an area of 2° and lying a mere 415-444 light years away. In fact through binoculars you can see nine prominent stars, two of which are the parents of the seven sisters. The stars are of varying brightness and distances from Earth. They vary from Magnitude 2.9 Alcyone 240 light years to Celaeno magnitude 5.5 and 590 light years distant.

The bright stars are middle aged hot B type Blue stars forming the closets star cluster to earth.  They formed approximately 100 million years ago. The nebula is not related to the stars and is just illuminated interstellar dust. 

This formation of stars (6) is know as Subaru in Japan (to unite).  It was chosen as Subaru brand of cars which united 5 companies into one thus the 6 stars depicted for their logo.