Category: emission

Elusive Continent

NGC 7000

NGC 7000 – The North America Nebula
By Rony De Laet

How many summer nights have I been looking to find this great nebula? I’ve tried with a 10cm f10 newton, a 20cm f10 dobson, an ETX 105 f14. But no result. This year I was armed with a widefield low budget SkyWatcher plus a 32mm Televue eyepiece and a Lumicon UHC filter. And there it was, a distinct glow with the shape of a continent! How beautiful, and finally I saw it in my sky. Here is the sketch. I also tried to render the effect of the UHC filter on brighter stars. Somehow this filter produces large halo’s around the brighter stars.

Date : September 15, 2007
Time : 21.30UT
Scope : Skywatcher 102/500
TV Plössl 32mm
Power : x16
FOV: 150′
Filter : Lumicon UHC
Seeing : 3.5/5
Transp. : 3/5
Nelm : 5.2
Sketch Orientation : N up, W right.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.

Note:
Rony De Laet discusses his sketching method here: About the Drawings
His gallery can be found here: My EXT-105 Project

Eta Carinae from Haleakala

Eta Carinae Complex and NGC 3293
By Jeremy Perez

Move mouse over image to see labels. Click for larger image.

The observing highlight of an evening atop the summit of Haleakala in Maui was gazing through my binoculars at the rich starscape in the vicinity of Eta Carinae. I had not done any homework on the area beforehand, so I approached it with unexpecting eyes. The mottled depths of the surrounding Milky Way, the smattering of intensely bright foreground stars, the abundance of open clusters of all shapes, sizes and intensities, and the stunning patches of glowing nebulosity made the whole region a delicious feast for the eyes. One incredible open cluster to the northeast, nearly took my breath away, but I did not have time to even attempt a sketch of it. Instead, I chose to render the region bracketed by the Eta Carinae complex and a much more manageable cluster, NGC 3293.

Eta Carinae was a brilliant orange star that surrounded itself in a plush comfort of nebulosity. This misty region ended abruptly to the south and then emerged again to surround a trio of bright stars. The observation and sketch were done more hastily than I would have liked and I know there was more detail to be extracted from this bright nebula, but I took what I could get. The northwest side of the view was punctuated by the small, bright open cluster, NGC 3293. Four bright stars announced themselves within its glowing boundary of unresolved starlight.

This section of the sky is still beckoning me, and I know I will have to return to it again with more time to spare. Even if I only have binoculars again the next time, it will still offer more than I can possibly absorb.

The sketch was created on Strathmore sketch paper with 2H and HB pencils. Nebulosity was shaded with a blending stump loaded with graphite. Color was added to Eta Carina in Photoshop.

Object Information

Eta Carinae is one of the most massive stars in the universe and is likely greater than 100 solar masses. It is about 4 million times more luminous than the sun, but radiates 99% of this energy in the infrared. Due to its extreme mass, it is expected to go supernova within the next few hundred thousand years. In the meantime, as it rapidly sheds matter, it goes through sporadic, violent outbursts. The most recent outburst peaked in 1843 when Eta Carinae became a magnitude -1 star, second only to Sirius. This eruption generated a rapidly expanding plume of gas that now forms a fascinating dumbell shape.

Messier’s Swan

M17
M17 – The Swan Nebula
By Jeremy Perez

Observation Notes:
From Anderson Mesa, this nebula appears much larger than the typical swan shape that I see from home. The back of the swan is the brightest portion with the neck second brightest. The head appears to have a crest, and fainter wings appear above the body. The tail flows out to the southeast and then in multiple flowing arcs to the northeast and back around to the northwest.

I chose the 25 mm Plössl eyepiece to capture the full extent of nebulosity in its 66 arc minute true field of view. There was a bright yellow-orange star to the northwest of the nebula as shown in the image. This sketch took 2 hours to complete, but the sky was clear and the experience was enjoyable. My only concern was that it would sink too far into the murk in the southwest before I finished. 172 stars are plotted in the sketch.

I used 2H and HB graphite leads to plot the stars, and a blending stump loaded with graphite to shade in the nebula. After scanning and inverting the sketch I used a soft, mostly transparent brush to add a bit of glare around the brighter stars and added color to the yellow-orange star on the northwest side of the view.

Object Information*:
M17 is a region of star formation that shines by excited emission of light from radiant young stars within. The stars that heat and illuminate this nebula aren’t readily visible, but are hidden within. It is estimated that a small cluster of about 35 of these stars are imbedded in the nebulosity.

Photographically, the color of the Swan Nebula is reddish. This color comes from the hot hydrogen gas excited to shine by the hottest stars which have just formed within the nebula. However, the brightest region is actually a white color. This white color isn’t just a photographic overexposure as I had thought, but is apparently a result of a mixture of red emission light, together with reflections of the bright star light from the dust in that region. The nebula also contains a large amount of dark obscuring dust, which is responsible for giving it its distinctive shape. However, even this dark dust is glowing brightly in the infrared spectrum, heated by hidden young stars.

The bright portion of the nebula extends roughly 15 light years, but the total cloud seems to extend at least 40 light years. The amount of matter in the cloud is estimated at about 800 times that of the Sun, which makes it more massive than the fantastic Orion Nebula (M42). It’s estimated that M17 is 5,000 to 6,000 light years away. It was discovered by Philippe Loys de Chéseaux in 1745-46, but wasn’t widely known, and so rediscovered by Charles Messier in 1764. Under very favorable conditions, M17 is just visible to the naked eye.

This object is known by a number of common names: Swan, Checkmark, Horseshoe, Omega. It is also catalogued as: Cr 377, Lund 827, LBN 60, Sh2-45, h 2008, GC 4403, OCL 44.

*Source: SEDS; ngcic.org

Starry Nursery

M42 

M42 and it’s close neighbor M43 are a delight to observe through any size telescope.
I captured these beauties on a clear August morning in 2006. This sketch was
rendered on Strathmore Windpower Sketch paper with a General’s Extra Black Layout
Pencil. Post processing and color added with MGI Photosuite III.

Jason Aldridge
North Port, FL

Spider or Demonic Face?

Tarantula Nebula 

Medium: graphite pencil and ink on white paper. 20inch f/5 Dobsonian at
Warrumbungles Mountain Lodge, New South Wales, Australia during the Deep South Texas Star Party (this is actually held in Australia) in March 2007. Some, obviously, see
a spider in this incredible deep sky object – I on the other hand see a Hollywood
demonic face snarling at us! Rather fun really when looked at from the safety of 170
klyrs away! Magnification was 212x and actual field of view 0.4 deg.

Rob Esson
Australia

A fine and Royal bird

Swan Nebula 

 The window of opportunity to explore the treasures of Sagittarius
is fairly brief from my 52 degree latitude observatory. This
coupled with the fact that my southern horizon  looks towards the
closest town 2 miles away with the sprawl of London starting just
25miles further on make for challenging observing especially of
diffuse objects.
  
  M17 the Swan or Check Mark nebula is one of the objects which I can get good views
of and one that visitors to my optics agree matches well with its name.

  Last week I caught up with this fine and Royal bird swimming on its stellar river.
The view prompted me to dig out this sketch from a couple of seasons back to share
with others.
  
  Scope used 14″ F5 Newtonian at 77x UHC Lumicon filter.HB pencil & blending stump
on white cartridge paper, scanned and saved as a negative with no enhancement.
From the Chippingdale Observatory, Hertfordshire, England.
  
  Clear Skies, Dale

Sparkling Lagoon

M8 

14th June, 2007., around 21:00 UT
Petrova gora, Croatia

Last night I had another opportunity to observe. But this time, we went
to the Petrova gora, mountain maybe 1000 ft high, about 40 miles South
from the Zagreb and 20 miles South-East from the Karlovac (pop: 60 000).
Light pollution is still evident on northern horizon but to the South,
skies are beautiful. NELM near zenith was 6.10, not much difference from
the best night in my backyard (NELM 5.80) but big difference is that
there is no glare from street lamps and glow from nearby populated
places so sky is much darker. Watching MW composed from many clouds,
with few bright spots (M24, M8, M25), seeing M7 by naked eye is
wonderful feeling. Statement that there is no substitute for dark skies
hold very well. Of course, I used this opportunity to make more
sketches. I hope you will like results.

My process of creating sketches goes like this:
First, I observe and draw field sketch, full of notes, corrections and
other helpful stuff. After returning to house, I redraw all sketches to
include missing details, remove errors and to get better contrast under
white light. Next step is scanning of sketches. Afters scanning, I do
further adjustments of contrast in the Photoshop and add circle
representing that represents FOV. Last thing is description and saving
sketch in .tff and .jpg format.

I’m sketching on plain A4 paper with graphite pencils of different
hardness.

Vedran Vrhovac

Terrific Trifid

M20 

Emission Nebula M20

14th June, 2007., around 21:30 UT
Petrova gora, Croatia

Last night I had another opportunity to observe. But this time, we went
to the Petrova gora, mountain maybe 1000 ft high, about 40 miles South
from the Zagreb and 20 miles South-East from the Karlovac (pop: 60 000).
Light pollution is still evident on northern horizon but to the South,
skies are beautiful. NELM near zenith was 6.10, not much difference from
the best night in my backyard (NELM 5.80) but big difference is that
there is no glare from street lamps and glow from nearby populated
places so sky is much darker. Watching MW composed from many clouds,
with few bright spots (M24, M8, M25), seeing M7 by naked eye is
wonderful feeling. Statement that there is no substitute for dark skies
hold very well. Of course, I used this opportunity to make more
sketches. I hope you will like results.

My process of creating sketches goes like this:
First, I observe and draw field sketch, full of notes, corrections and
other helpful stuff. After returning to house, I redraw all sketches to
include missing details, remove errors and to get better contrast under
white light. Next step is scanning of sketches. Afters scanning, I do
further adjustments of contrast in the Photoshop and add circle
representing that represents FOV. Last thing is description and saving
sketch in .tff and .jpg format.

I’m sketching on plain A4 paper with graphite pencils of different
hardness.

Vedran Vrhovac

A work in progress

M42 

The Orion nebula may be one of the most challenging objects in the sky to observe.
The amount of  subtle detail it displays is astonishing and it is perhaps one of the
most difficult nebula to sketch.

Edward Holden’s monograph on the central area of M42 (Central Parts of the Nebula of
Orion, Washington Astronomical Observations for 1878, Appendix I) inspired me to
attempt to follow the footsteps of great visual observers of the the past — the
Herschels, Lassell, Rosse, Bond, etc.– and try to capture the wealth of details
seen in my 18″ reflector. I might add that my sketch is a composite drawing made
with apertures ranging from 70mm to a 20″ reflector. A separate drawing was made on
each evening of observing and combined into a single rendering. The Dearborn
Observatory star maps (claimed to go down to the 18th magnitude) were used to insure
the proper “placing” of the details noted with the various telescopes. The
(unfinished) drawing is still a work in progress after two years of observing.
Magnifications on my 18″ reflector ranged from ~60X (40 mm Pentax) to ~460X (5mm
Radian). The lowest power used: 12X with my Pronto 70mm refractor!

I settled on using a graphite pencil after experimenting with charcoal and soft
lead pencils. Nothing fancy here — just graphite on regular (economy) typing
paper from Office Depot. The drawing was color-inverted using my HP scanner and
tinted with the Paint program.

An extended observing session revealed details I hadn’t noticed before. The
remarkable D’Arrest “comets” were visible only when the transparency was good. The
prominent dark “globule” W1 was seen so well through a 24″ reflector one evening
that my first impression was that there was a bit of dirt on the field lens of my
eyepiece!

I hope that in another two years I can finish the drawing.

Dave Riddle

The winter King

M42 

Sketch of M42 drawn with graphite pencil on white paper, hand made directly
looking throught the 12 x 80 binoculars sitting in a quiet place in the
centre of Guadalajara country.

The night was very clear and transparent, without clouds and no pollution. I
was drawing it looking with both eyes, it was wonderful because the nebula
was very bright, three nebula regions were visible surounding star clusters
(north and south of M42)

I scanned the sketch and changed to negative only. This is my first M42, I
remember the night was very cold and the pain in my fingers while drawing
it. The image through the binoculars was esplendid, impresionant, very
bright, impossible to draw all the stars in the field.

I hope you enjoy it.

Leonor Ana