Category: open clusters

 

Original sketches are with a # 2 pencil, earser & rubbing stump on white paper

Originals are then scanned into PhotoShop and traced for accuracy of colors and
refinement.

All images have other pertinent information included.

Wade V. Corbei

 Object Name: NGC 6939 (H.VI.42)Object Type: Open Cluster

Constellation: Cepheus

Right Ascension (2000.0): 20h 31.4m

Declination (2000.0): +60° 38′

Magnitude: 7.8

Diameter: 8′

Trumpler Type: I 1 m

Telescope: Parks Astrolight EQ6 • 6″ f/6 Newtonian Reflector

Eyepiece: 7.5mm Parks Gold Series Plössl • 120x, 26′ FoV

Date & Time: 8 September 2007 • 03:30 UT

Seeing Conditions: NELM 6.3 • Pickering 8

Observing Location: Cuyamaca Mts., San Diego Co., California

Sketch Information: Digital rendition based on paper and pencil eyepiece sketch.

NGC 6939 is a subtle, yet beautiful open cluster in the southwestern reaches of
Cepheus, near the border with Cygnus.  NGC 6939 is famous for sharing a low-power
field of view with the spiral galaxy NGC 6946; this celestial odd-couple has been
the target of countless astrophotographs.  The juxtaposition of these two objects is
equally accessible to the visual observer with access to dark skies and a field of
view wide enough to accommodate the 38′ that separate the duo.

The most expeditious way for the star-hopper to locate this object is to center your
scope on 3rd magnitude Eta (η) Cephei and sweep about 1.5° east and just over 1°
south with your lowest-power, widest-field eyepiece.  At 30x, I see a fairly
conspicuous patch of nebulosity studded with a few dozen faint stars nestled in a
very rich patch of the Milky Way.  The spiral galaxy NGC 6946 glows feebly ½° away
to the southeast.

Zeroing in on this stellar concentration with higher magnifications brings out a
delicate array of faint stars ranging from magnitude 11 down to 14 and beyond.  The
soft, often glittering haze of unresolved stars persists in the background even at
high magnifications.  The stars seem to be arranged in strands stretching toward the
east like gleaming dewdrops in a broken spider’s web.  In that direction (east) it
is very difficult to discern where the cluster ends and the starry expanse of the
Milky Way begins.  The western edge of the cluster, in contrast is sharply defined,
particularly on the southwestern side.  This sudden drop-off in the stellar
population gives me the impression of an interposing finger of dark nebulosity
thrusting northwestward.

Sir William Herschel discovered NGC 6969 on September 9, 1798 with his 18.7-inch
reflector.  This cluster lies at a distance of about 4,000 light-years and is
believed to be 1.8 billion years old based on the Hertzsprung-Russell diagram of its
constituent stars.

Eric Graff

 

M 44, also called Praesepe or Beehive, is one of the greatest Open
Clusters of the night sky. Consisting of many bright stars, it is
already visible with the naked eye, the best view, however, is provided
by binoculars or a rich field telescope, which show M 44 in all her
magnificent beauty. The 1.5° FOV the Newtonian provided, when I sketched
this, was already way to small to show all the stars belonging to this
great cluster.

Date: December 24, 2006
Location: Steinwald, Bavaria, Germany
Instrument: Vixen Newtonian 4.5″ f/6 on Vixen GP
Constellation: Cancer
Seeing: Antoniadi II
NELM: 6m0
Bortle: 5
Magnification: 45x

Sebastian Lehner

 

Hi folks,

Here’s my first observation with the SkyWatcher. This rich field scope gives a whole
new perspective on deep-sky objects. With a SP 26mm EP, I get a whopping 2.7 degrees
field of view at a power of x19. I hope you like the view.

Date : March 8, 2007
Time : 20.30 UT
Seeing :2.5/5
Transp. 3/5

Digital sketch made with Photopaint, based on a raw pencil sketch made behind the EP.
N down, W left orientation.
Rony De Laet

http://www.geocities.com/rodelaet, my personal website.

 

Melotte 111

Hello sketchers,

What is called the second closest star cluster to our sun? Looking at it with a
scope is of little use, because the grouping covers about 5° of sky. Some of its
stars look so bright in a scope, as if one can almost touch them. So here it is, my
impression of this beautiful naked eye cluster. I used the lowest power available,
but even the fov of 3° is not large enough to cover the cluster. So the sketch is a
composite image of overlapping observations. Because of the low power, the sky-glow
washes out al stars fainter than mag 10.9. I hope you like my impression.

Date : May 5, 2007
Time : 22.00UT
Scope : SkyWatcher 102/500
TV SP 32mm eyepiece
Power : 15
FOV: 5°
Filter : none
Seeing : 2.5/5
Nelm : 5.1
Sketch Orientation : N up, W right.
Digital sketch made with a digital tablet and PhotoPaint, based on a raw pencil sketch.

Rony De Laet

http://www.geocities.com/rodelaet, my personal website.

 

Here is a lawn chair observation under the freezing Austrian sky at 800m asl. It is
a simple but pleasant sketch of the Bull’s face. I was surprised to notice 3 pairs
of stars. The sky was not perfect dark, so there should be more stars to be picked
out from the cluster. Anyway, scopeless stargazing can be fun ! No cooldown time
needed. My legs and hands cooled down anyway at -9°Celsius. (a solid fuel hand
warmer is a must have)

Location : Bischofshofen, Austria
Date:  Dec. 25, 2006 , 20.30UT
Seeing:  4 on a scale of 5, Transparency : 4
Air Temp.: -9° Celsius
Naked eye observation
Rony De Laet

http://www.geocities.com/rodelaet, my personal website.