Attracting an Extragalactic Visitor

M79

Messier M79 in Lepus
By Rony De Laet

Here is an observation of M79. From my location, the object rises only 15° above the horizon. 15° sounds like a solid number, but it is not when tried out in the field. I was surprised to find M79 easy at low power. The sketch is made at 63x. The core appears almost stellar. One faint star was visible with averted vision N of the globular.

Date : February 5, 2008
Time : around 20.30UT
Scope : Skywatcher 102/500
Eyepiece : Hyperion Zoom at 8mm
Power : x63
FOV: 65′
Filter : none
Seeing : 2,5/5
Transp. : 2,5/5
Nelm : 4,8
Sketch Orientation : N up, W right.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.

A Mighty Globular in a Small Scope

M3 globular cluster

Messier 3 Globular Cluster
By Rony De Laet

Hello folks,

Summer is approaching, the nights have become grey. But I do not stop observing. Here is an impression of M3. I had fun teasing out as much detail as possible. Globulars are difficult to render. The mind might see patterns that aren’t there. I tried to remain objective. Lots of faint stars were present in the outer region of the halo. I noticed some dark lanes in the halo, and the core looked elongated too. I hope you like the view.

Date : June 5, 2007
Time : 22.30UT
Scope : ETX 105/1470
Meade 25mm and 15mm SP
Power : x66 to x100
FOV: 35′
Filter : none
Seeing : 2.5/5
Transp. : 2/5
Nelm : 4.9
Sketch Orientation : N up, W right.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.
 

M22 from Anderson Mesa

M22

Messier 22 from Anderson Mesa on July 12, 2007
By Jeremy Perez

I was feeling pretty worn out when I made the trip to Anderson Mesa and wasn’t sure that I wanted to tackle a monster observation like M22. But I’m glad now that I did. It really called for a lot more detail than my previous observation and sketch gave it. This globular cluster really is huge. At 120X, it occupies a large portion of the view, and I would estimate its visible dimensions at roughly 11 arcminutes in diameter. It is resolved all the way across its surface. Clumpy structure can be seen in its brighter core, and ribbons of light and dark can be seen running across its grainy outer halo–most prominently on its southwest side. A bright orange star marked the northeast edge of the field. The sketch took about an hour and twenty minutes to complete at the eyepiece, and another twenty minutes refining the stippling indoors later.

Object Information:

At 10,400 light years distant, M22 is one of the nearer globular clusters. Its angular diameter is slightly larger than the full moon and works out to 97 light years in diameter. It is receding from us at about 149 km/sec. Recent Hubble Space Telescope investigations have led to the discovery of a number of planet-sized objects that appear to float through the cluster. They have masses of only 80 times that of Earth and were discovered from the gravitational lensing of light from the numerous background stars they pass in front of. M22 was most likely first discovered by Johann Abraham Ihle in 1665, and later cataloged by Charles Messier in 1764.

This cluster is also catalogued as ESO 523-SC004, GCL 99, h 2015, h 3753, GC 4424.

Subject M22 / NGC 6656
Classification Globular Cluster (7)
Position Sagittarius [RA: 18:36:24.1 / Dec: -23:54:12]*
Size* 24′
Brightness* 5.2 vMag
Date/Time July 11, 2007 – 10:00 PM MST (July 12, 2007 – 05:00 UT)
Observing Loc. Anderson Mesa, AZ
Instrument Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag. 10 mm Sirius Plössl(120X)
Conditions Mostly clear, calm
Seeing 5/10 Pickering
Transparency ~ Mag 6.8 NELM
* Based on published data.

A Stellar Swarm in Pegasus

M15

M15
By Barry Chase

Perhaps the most dense of the Milky Way’s globular clusters, M15 lies about 33,600 light years away and is about 175 light years in diameter. It has undergone a core collapse and half the mass of the cluster resides within a 10 light year radius of its center. It is not clear whether this dense concentration is due to the gravitational interactions of the clusters stars, or if it is due to the influence of a supermassive object–a black hole–at its core. M15 is also the first globular cluster in which a planetary nebula was found. (This planetary nebula, Pease 1, is a considered a challenging target for amateur astronomers with large telescopes, dark steady skies, and lots of patience.)

Source: SEDS

Oddly Fascinating

M56 

Now here is a Globular that struck me as fascinating and odd at the same time. Although the stars resolved quite well, it also appeared very dim for as well as it resolved…strange.

The digital sketch based on my original pencil drawing took a little time to depict accurately. I was either getting it too bright or too dim, and getting to the point of making the digital sketch appear as it looked to me through the EP was a task. I believe I had 5 or 6 dufferent layers with differing opacities and Guassian Blurs applied before I got it to resemble the actual EP view.

This Globular is framed nicely by background stars of varying brightness, and set off this Globular quite nicely. Here is how it appeared to me through the EP, I hope you enjoy it.

Wade V. Corbei

One Hundred Thousand Strong

M5

I find Messier 5 to be one of the most beautiful globular clusters in the catalog.
Individual stars resolved nicely around a bright core at medium magnification.
This sketch was rendered on standard copy paper with a .5mm mechanical pencil. Post
processing was done with MGI Photosuite III.

Jason Aldridge
North Port, FL

Sphere of Influence

M13 

M13 – Globular Cluster

This was both a tough one and a fun one that presented some unique challenges. At
one time, I had a total of 21 layers and two separate documents in PhotoShop just to
get this thing looking halfway decent. My first challenge was, of course, the
Globular itself. I took notes to share some of the steps involved in digitizing this
sketch to share with others here.

Globular:

I started with a copy of my scanned image and reduced the opacity to 30 percent.
This allowed me to see the sketched image while making it transparent enough to see
the black background of the background layer.

I then created another layer behind the sketched image layer, chose the elliptical
selection tool and made a circle approximately ¾ the diameter of the globular
cluster, and filled it with 100 percent white. I then made a copy of this layer and
hid it for the time being. I then applied a Gaussian Blur of 9.7 to the first white
circle to soften it and create a glow. The opacity of the layer was then reduced to
30 percent to achieve a bright but subtle glow. I then used the blur tool with a
brush size of approximately 150, centered it over the blurred white circle, and
blurred the image a couple of times to get the proper effect.

I then made the copied white circle layer visible and applied a series of splatter
brush strokes to fill in the center of the globular. I’d make a brush stroke, copy
the layer, and rotated it 90°. I then applied another splatter brush; copied and
rotated until I got the star-scatter that closely resembled my original sketch. I
used the eraser tool quite a bit to get rid of stray or out-of-place stars.

I then created another layer and, using the paintbrush tool, used a variety of brush
sizes from 1-4 to add the stars immediately surrounding the Globular. The opacity
was changed from anywhere to 25 percent to 50 percent depending on the particular
stars or series of stars I was recreating and to create a bright, but not too bright
look to the stars.

I copied the above layer and set the opacity to 60 percent and set the layer mode to
difference. This softened the edges while maintaining a bright core to the stars.

Background Stars:

This is where the fun (and time) began. As many of the fainter stars were seen with
diverted (averted) vision, I had to create a way to try and make the stars appear as
I actually saw them. A weird combination of bright, but not so bright as to be
blinding, yet dim enough that it takes a second look to see them.

Once again, I started with the paintbrush tool set to a diameter of between 1 and 3,
and placed the stars as they appear in my original sketch. (Remember, the original
sketch is still visible on its own layer, just at a reduced opacity) The opacity of
these background stars never exceeded 60 percent. I tried to increase the opacity,
but then the stars started to look artificial.and definitely not how I actually saw
them.

I actually created 3 separate layers for this. One for a brush size of 1, another
for a brush size of 2, and the last for the brush size of 3. This way I could
control the opacity of the separate size/dimness of the stars separately without
effecting the entire digital star-field.

Once I had all my background stars in place, I linked the 3 layers, merged them
together, and made a copy. This made them stand out a little more, but still a
little too artificial, so I set the layer to overlay mode, and reduced the opacity
to 56 percent. I then merged all the background star layers, the globular layer, and
the blurred layer together. I then made a copy of this master layer.

I opened a new document in PhotoShop, and pasted the copied layer. I reversed the
image to a negative. Using the color picker, I removed all the white background,
leaving me with just the black reversed stars and Globular.

I then dragged and dropped this layer back into my original document. A quick Ctrl
+A+X+V cut and centered this negative image exactly over the original image. I then
moved the negative image behind the original, and applied a Gaussian Blur of 2.5.
This helped to darken the area behind the original stars and created a warm glow.

At this time, all layers except the black background layer were merged. I then used
the blur tool to soften those stars that still appeared too bright, as well as
utilizing the Burn and Dodge tools to adjust brightness as needed.

The result of all this is my digitized version of M13 based on my original sketch.
The original sketch took me about 30 minutes, and the digitized reproduction took me
roughly 30+ minutes. This has so far proven to be my most involved sketch and
digitized reproduction.
I hope it is acceptable.

Wade V. Corbeil

Sweet stellar spoonful

M15

Dear Skycombers,
   
  Messier 15 is a splendid globular cluster, granulation is fine when compared to
Messier 13 and Messier 5 ‘Salt rather than Sugar’. It is, I hope you agree a
beguiling spectacle, a veritable stellar cornucopia no less.
  
  Drawn with graphite pencil on white cartridge paper and converted to negative post
scanning without enhancement.
  
  7.9.2007,  22:40UT
   Location: Chippingdale observatory, Nr Buntingford, Hertfordshire, UK
  14″ F5 Newtonian at 118x giving a 0’35” FOV
  Seeing Ant 11-111 transparency was good.
  
  Dale Holt

Ancient stellar city

M92 

M92 is near the top of the list for me when it comes to globular clusters. It takes
magnification extremely well, and many individual stars are clearly resolved around
a bright core. M92 would probably get more attention were it not for it’s
spectacular neighbor, M13.

This sketch was rendered on standard copy paper with a .5mm mechanical pencil. Post
processing was done with MGI Photosuite III.

Jason Aldridge
North Port, FL

Distant Globular in Hercules

NGC 6229

  Large globular clusters are always rewarding targets to hunt down from less than
ideal sky locations. In a 10” telescope from urban/suburban locations only the 9th
magnitude glow of this globular is clearly visible. Upon closer inspection the
core can be seen to brighten significantly. The angular size of this cluster looks
to be about 1.5 minutes of arc in the eyepiece. It is easy to see why 18th and
19th century observers thought this globular to be a planetary and on at least one
occasion it was reported to be a comet. At almost 100,000 light years distant, it
is challenging to resolve stars in this globular without at least 13 inches of
aperture. I could not resolve any stars of the cluster with the 10” scope. The
brightest stars in this globular cluster are about magnitude 15.5. Adding to the
eyepiece view are two well spaced 8th magnitude stars to the west listed in the
Henry Draper catalog as HD151689 and HD 151651.
  
  Sketching Date and Time: 8-12-2007, 2:30-2:50 UT
  Telescope 10” f / 5.7 Dobsonian 21mm eyepiece 69x
  8”x12” white sketching paper, B and 4B graphite pencils, a blending stump, scanned
  and inverted
  Seeing: Pickering 7/10
  Transparency: average 2.5/5
  NELM 4.1
  
  Frank McCabe