OPEN STAR CLUSTERS
M-11 (NGC-6705): An exceptional galactic open cluster, located in the constellation of Scutum. This rich
cluster contains 400 stars brighter than 14th magnitude. Its visual size is approximately 12 minutes of arc,
which at its accepted distance of 5500 light years translates to a diameter of approximately 20 light years.
NOTE:  This image was captured on 8/17/2012 and is an integration of fifteen 50 second exposures through
the 11-inch Celestron at f/2 using HyperStar and the SXVR-H694C color CCD imager. Captured and
combined using Maxim DL 5 Pro. Post-processed using Photoshop CS, levels, curves, Astro-tools and
Gradient X-terminator. Noise filtered andconverted to JPEG format using NoiseWare.
(CLICK ON THUMBNAIL IMAGE FOR FULL-SIZE VIEW)
M-71 (NGC-6838): Located in the constellation Sagitta, approximately midway between the stars Delta and Gamma
Sagittae. It lies approximately 12,000 light years from Earth and is about 27 light years across. It was long thought to be
an extremely dense open cluster because it lacked the dense central compression found in globulars and lacked the
RR Lyrae type variable stars usually found in globulars. However, modern photometric research has detected a short
"horizontal branch" in the H-R diagram of stars in M-71, lending credibility to the fact that it MIGHT, in fact, be a loose
globular cluster.
NOTE: This image was captured on 8/11/2013, and is an integration of fifteen 60 second exposures through the
11-inch Celestron at f/2 using HyperStar and the Starlight Express SXVR-H694C 1-shot color imager. Captured and
combined using Maxim DL Pro v. 5.2. Post-processed using Photoshop CS, levels, curves, color balance & saturation,
and Gradient X-terminator and Astro-Tools.
NGC-7789: Located in the constellation of Cassiopeia, between the stars Rho and SigmaCassiopeiae. A very rich
galactic open star cluster. It contains almost 1,000 stars, and its visual size is approximately 20 minutes of arc, which
translates to an actual diameter of about 50 light years, given its accepted distance of 6,000 light years. Spectroscopic
study reveals this cluster to be much older than most open clusters.
NOTE: This image was captured on 9/1/06, and is an integration of ten 90 second exposures through the 80mm f/7.5 ED
Apochromatic Refractor. The images were combined and processed in Maxim DL Essentials, with additional
post-processing in Photoshop CS.
M-46 (NGC-2437): Located in the constellation of Puppis, about 14 degrees east of the brilliant star Sirius (Alpha
Canis Majoris). Discovered by Charles Messier in 1771. It contains about 200 stars ranging from 10th magnitude
down to 14th magnitude and has a visual size of approximately 25 minutes of arc. The brightest members are
blue giants of spectral class AO, each having a true luminosity of over 100 times that of the sun. This cluster lies
at a distance of about 5400 light years from earth. A curious feature of this cluster is the presence of the small
planetary nebula NGC-2438, located approximately 7 arcminutes north of the center of the cluster. It shows up in
this CCD image just to the upper right of the center of the cluster. It is believed that the nebula is not actually a
member of M-46, as its radial velocity indicates that it is probably 3300 light years from earth. This means that it is
an "optical" or "line of sight" member of the cluster.
NOTE: This image was captured on 3/14/2013 and is an integration of six 240-second exposures
through the C-11 at f/2 using HyperStar and the SXVR-H694C camera. Captured and combined using
Maxim DL 5. Post processed in Photoshop, levels, curves, gradient X-terminator and NoiseWare.
M-36 (NGC-1960): Located in the constellation of Auriga. A bright open star cluster con-
taining about 60 stars ranging in magnitudes from 9 to 14. Most of the brighter members are all B-type
blue-white stars. This is one of the younger open clusters in the milky way. It lies at a distance of
approximately 4100 light years from earth. At this distance, the angular size of the cluster, 12 arcminutes,
translates to an actual diameter of about 14 light years.
NOTE: This image was captured on the evening of October 30, 2008, and is an integration of twenty-five
25 second exposures through an 80mm APO refractor at f/3.75. The image were captured and combined  
usingMaxim DL Essentials, with additional post-processing using Photoshop CS and Astro-Tools.  Noise
filtered and converted to JPEG format using NoiseWare.
M-37 (NGC-2099):_A superbly rich open cluster in Auriga, considered one of the finest of the three Messier
open clusters in that constellation. M-37 contains over 150 stars ranging in magnitude from 9 to 12.5. The
stellar population of this cluster is very different from M-36, and suggests that the cluster is much older. It
also contains several red giants, which stand out like rubys in a field of white diamonds. M-37 lies at a
distance of 4700 light years and is approximately 25 light years in diameter.
NOTE: This image was captured on the evening of December 27,2013, and is an integration of four 240
second exposures through the 11-inch Celestron at f/2 using the SXVR-H694C imager. Captured and
combined using Maxim DL 5 Pro. Post-processed using Photoshop CS levels,curves & Gradient X-terminstor.
M-38 (NGC- 1912) and NGC-1907 (to the right - west): M-38 is a large bright open cluster in Auriga,
located about 2.3 degrees NW of M-36. It is a scattered group of irregular form,oriented NW to SE. It is
approximately 20 arcminutes in diameter, which at its calculated distance of 4200 light years corresponds
to an actual diameter of about 25 light years. The smaller, more compact open cluster NGC-1907 lies just
at the west edge of the field of this image.
NOTE: This image captured on October 30, 2008. It is an integration of twenty-five 25 second exposures
through the 80mm APO refractor at f/3.75. Combined and processed inMaxim DL Essentials, with
post-processing using Photoshop CS and Noiseware.
M-35 (NGC-2168) and NGC-2158: M-35 is a beautiful open star cluster in the constellation of Gemini.
First cataloged by de Cheseaux in 1745 and cataloged by Messier in 1764 as the 35th object on his list.
Visually, M-35 is about 30 arcminutes in diameter when viewed through modest  sized telescopes. It lies at
a distance of approximately 2200 light years from earth. It containsabout 120 stars ranging from B3 to G0
in the main sequence. Most of the members are 8th to10th magnitude. About 1/2 degree SW (upper right
in the image) from M-35 is the very rich and distant cluster
NGC-2158. This cluster is actually the same
physical size as M-35, but lies over 8 times further away than M-35. Modern measurements place its
distance at over 18,000 light years. Through 8 to 12 inch telescopes, NGC-2158 appears as a very rich
compressed cluster,somewhat triangular in shape, with a misty, granular texture.
NOTE: This image was captured on 3/14/2013 and is an integration of five 240 second exposures through
the C-11 at f/2 using HyperStar and the Starlight Express SXVR-H694C color imager. Captured and
combined using Maxim DL 5 Pro v. 5.2. Post processed in Photoshop CS, levels, curves, Astro-tools,
Gradient X-terminator and NoiseWare.
M-52 (NGC-7654): The brightest open cluster in the constellation Cassiopiea, located on the western edge of the
constellation. M-52 is a large, rich, fairly compressed cluster, which contains almost 120 stars from 9th to 12th
magnitude. It lies approximately 3000 light years from earth and is about 15 light years in diameter. The two
brightest members of the cluster are yellow giants of spectral class F9 and shine at 7.8 and 8.2 magnitude.
NOTE: This image was captured on the evening of 11/5/2010, and is an integration of twenty-four 30-second
exposures through the 11-inch Celestron at f/2, using the HyperStar system. Captured in Maxim DL Essentials,
processed in Nebulosity v.2.2.8, post-processed in Photoshop CS, levels, curves & color balance. Noise filtered
using NoiseWare.  
M-21 (NGC-6531): An open star cluster located in western Sagittarius, just north of the Trifid Nebula (M-20).
It is a relatively young cluster, being less than 5 million years old. It consists of
57 stars, many of which are blue-white giants. It lies at a distance of approximatley 2500 to 4000
light years from Earth.
NOTE: This image captured on the evening of July 14, 2012 and is an integration of ten 90-second
exposures through the Celestron 11-inch at f/2, using the HyperStar 3 imaging system and the
Starlight Express SXVR-H694C 1-shot color CCD camera. Captured and combined using Maxim DL
5 Pro. Post-processed using Photoshop CS, levels, curves, star reduction and Gradient Exterminator.
NGC-6791: A very rich open star cluster located in the constellation of Lyra, the Lyre. This cluster is thought to be one
of the very oldest open clusters in our galaxy. Based on the heavy metal content of its member stars, which contain
over twice the amount of iron as our sun, NGC-6791 is estimated to be almost 8 billion years old. Because of this as
well as its density, it is one of the most studied open clusters in our galaxy.
NOTE: This image was captured on August 10th, 2012 and is an integration of fifteen 60 second exposures through the
11-inch Celestron at f/2 using the HyperStar 3 imaging system and the Starlight Express SXVR-H694C 6 megapixel
camera. Captured and combined in Maxim DL 5 Pro. Post-processed using Photoshop, levels & curves, AstroTools,
and NoiseWare.
M-6 (NGC-6405): One of the brightest galactic star clusters, and one of the nicest to observe
using a small telescope. Located 5 degrees north of the "tail" of Scorpius the Scorpion. It is an
oblong cluster of approximately 50 stars ranging from 6th down to 10.5 magnitude. Due to its shape it is
sometimes called "The Butterfly Cluster". It lies approximately 1500 light years from Earth:
NOTE: This image was captured on the evening of September 10, 2012 and is an integration
of fifteen 50-second exposures through the 11-inch Celestron at f/2 using HyperStar and the
SXVR-H649C color CCD imager. Captured and combined using Maxim DL 5 Pro. Post
processed using Photoshop CS, levels, curves, and Gradient X-terminator. Noise filtered and
converted to JPEG format using NoiseWare.
M-45, The Pleiades Cluster: Located in Taurus, The Bull, this is one of the nearest open
clusters, being only 400 light years from Earth. It is a very young cluster, only 100 million years
old, and is dominated by hot, extremely luminous blue-white stars. The cluster is enveloped in
a cloud of interstellar dust which is not related to the formation of the cluster, but which the
main stars are currently passing through. The most famous part of the dust cloud is the
reflection nebula surrounding the star Merope, seen at the right center of the image.
NOTE: This image was captured on November 8, 2013, and is a composite of eight 6-minute
sub-exposures through the 11-inch Celestron at f/2 using HyperStar and the Starlight Express
SXVR-H694C CCD Camera. The images were captured using Maxim DL 5 Pro. Post-processed
using Photoshop CS, levels, curves, color balance & saturation, and Gradient X-Terminator.
M-93 (NGC-2447)  A bright open cluster located in the constellation of Puppis. Discovered by Charles Messier in 1782.
It is located approximately 3600 Light Years from Earth and is approximately 12 light years in extent. It is a relatively young
cluster, about 100 million years old. The brightest members of the cluster are blue giants of the type B9.
NOTE: This image was taken on December 28th, 2013, and is an integration of nine 4-minute exposures through the
11-inch Celestron at f/2 using the HyperStar system and the Starlight Express SXVR-H694C color CCD imager. Captured
and combined using Maxim DL 5 Pro. Post-processed using Photoshop CS, levels & curves, color saturation, and Gradient
X-terminator.