Category: open clusters

Binocular Beehive – M44

M44

M44
Sketch and Commentary by Rony De Laet

M44 in Cancer is a typical binocular object. With a total magnitude of 3.1 the Beehive Cluster or Praesepe was known since antiquity. And indeed, at a distance of 520 lightyears, the cluster is faintly visible as a large nebulous patch to the naked eye. With a simple pair of binoculars the patch resolves into a beautiful V-shaped open cluster measuring more than 1° across. Several multiple stars are visible at low power. The binocular view is perfect for such a large object. Most telescopes don’t offer a wide enough view to show the cluster in it’s ‘natural environment’. While studying the object, I got the impression of a deeper darkness behind the cluster, compared to the overal background brightness. Could this be an optical effect created by the contrast between the cluster stars and the background? I don’t know if it shows in the sketch. The bright star in the lower left part of the sketch is Delta Cancri. The one in the upper left corner is Gamma Cancri.

Observing data:
Date : March 31, 2008
Time : around 20.30UT
Binoculars : Bresser 8×56
FOV: 5,9°
Filter : none
Mount : Trico Machine Sky Window
Seeing : 2,5/5
Transp. : 2,5/5
Nelm : 5,0
Sketch Orientation : N up, W right.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.

Orange Embers and Blue Ice in Messier 18

M18

M18
Sketch and Commentary by Wade Corbei

Here is an older sketch that has been hiding in the middle of my current sketch book. As the date indicates, this sketch was made back in October of ’07 when Sagittarius was still fairly prominant towards the south.

My notes also make note that I was a little more than 1 hour at the EP while plotting all the faint stars that surround this great open cluster, and that there was no Moon in the sky, which allowed for some great dark-sky observing.

I also noted that this cluster had a few stars of varying colors as well, a few that were slightly orange as well as a few almost ice-blue. The rich starfield of this region just adds to the overall experience of observing this large OC. This is indeed a fairly large OC as well. Although I tried several EP’s (15mm Expanse, 10mm, 6.3mm) I got my best over-all view of this OC with my 20mm.

A Cluster Between the Two Dogs

M47

M47
Sketch by Michael Vlasov

According to the fine folks at SEDS, M47 lies about 1600 light years away, contains around 50 stars, and spans 12 light years. Overall, the population of stars is similar to that of the Pleiades. It contains two orange K-type giants with masses about 200 times that of the sun. It is estimated to be 98 million years old and is receding from us at 9 km/sec. Charles Messier cataloged it in 1771, but due to an error in marking its position, it was not recognized as a Messier object and so re-discovered by William Herschel in 1785. In 1984, a book by Hodierna came to light in which he described the cluster as “a Nebulosa between the two dogs” in 1654, making him the original discoverer on record.

A Ring in the Bouquet

M46

M46 (NGC 2437) and NGC 2438
By Kiminori Ikebe

From Mr. Ikebe’s observing notes:

M46 (NGC 2437) Pup open cluster Difficulty level 1

NGC 2438 Pup planetary nebula Difficulty level 3

Date of observation: 1998/11/21 03:29
Observing site: Hoshinomura
Transparency/seeing/sky darkness: 1/4/3
Instruments: 32cm Dobsonian with Er32 at 50x
Width of field: 1 degree

This is a large and bright open cluster. Even at 50x it is almost completely resolved. This fine cluster is filled with numerous pin-points of faint stars and very difficult to draw. This sketch shows it as nebulosity. There are also many bright stars embedded in this cluster. The neighboring M47 makes a good contrast with M46. M47 has fewer stars with unequal brightness. M46 presents itself as a dainty cluster while M47 shows its coarseness. Another similarly contrasting pair is NGC 2451 and NGC 2477 in Puppis. They are more contrasting than the M46 and M47 pair.

At this magnification the planetary nebula NGC 2438 is clearly seen. Its image overlapping with the open cluster is mysterious and unreal. It is rather large as planetary nebulae go. Switching to high powers a ring structure becomes clearer. This nebula is interesting by itself but it is usually viewed in association with M46 playing second fiddle to it.

(Mr. Ikebe’s sketch gallery can be found here: Visual Observation of Deep Sky Objects)

NOTE TO OUR VISITORS: Please accept my apologies for the lapse in updates for the last three days. I returned from a trip out of town to hear that Rich Handy has come down with pneumonia. He is getting some much needed rest and antibiotics and sounds like he is slowly getting better. I’ll work on keeping the posts going until he is feeling well again. Your submissions are always appreciated!

Jeremy Perez

Splendid encounter

Moon and Pleiades 

Hello astronomy’s lovers, this is my last sketches of Moon and Pleiades.The sky was
clear, but strong windy make many difficult for made the drawings. I stay in my
observation site in front of my home with bino 16×80 on the heavy wood’s tripod and
inox column, all very steady fortunely!!I make the first sketch at 8,25p.m.,second at
8,50p.m., last at 10p.m. What fantastic vision!
Title:”Splendid encounter”
Instrument:Binocular 16×80.
Mount:Wood’s trypod,inox column and photographic head.
Seeing:Good
Temperature:cold and strong windy.
Location:Pergola,Marche,Italy.
Date:March 12,2008.

Giorgio Bonacorsi

Seven Sisters over Georgia

M45 

Seven Sisters Over Georgia
By Carlos E. Hernandez

I was able to view the Pleiades (M45, or Seven Sisters) under dark and clear skies using my 10 x 50 Oberwerk binoculars while visiting my son in Georgia on November 21, 2007 (01:30 U.T.). The view was spectacular as the cluster sparkled in the field of view with many fainter stars visible. I hope that you all like it.

A digital image produced in Corel Painter X.

Carlos

Home of the Seagull

IC 2177

IC 2177, Home of the Seagull
By Rony De Laet

IC 2177 is listed in the ‘Deep Sky Travel Guide (Ronald Stoyan, Oculum)’ as : very large, very faint. This description was a challenge to me. Would I be able to see it? From the 5th of February, we were blessed with exceptional clear skies for a whole week. Every night, I scanned the sky between Sirius and M50, in search of IC2177. It took me four nights to track down the location of IC2177. Four nights of trial and error. Each time I eliminated the suspected location from the drawings I made. In my mind, I builded myself a path through the vast and complex milkyway section South of M50. The trick is to find NGC 2353. From there, starhop to NGC 2343 and put it at the 10 o’clock position in a low power eyepiece (binocular orientation!). Now the scope is amed at IC 2177. It sounds easy, but it isn’t, at least not in my sky with my little refractor. The journey is joyfull and the destination is very rewarding. The question still is : did I see it? I noted a dark rift running through the fov from the 11 o’clock to the 5 o’clock position. East of the rift, the sky seems to brighten a bit more than West of the rift. Or is it unresolved starlight? I look forward to reports from other observers. Here is the sketch. (The little triangular cloud at the 10 o’clock position near the border of the fov is NGC 2343.)

Date : February 11, 2008
Time : around 22.00UT
Scope : Skywatcher 102/500
Eyepiece : Meade SP 26 mm
Power : x19
FOV: 150′
Filter : UHC
Seeing : 2,5/5
Transp. : 2,5/5
Nelm : 4,7
Sketch Orientation : N up, W right.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.

Tail of the Great Dog

NGC 2362

NGC 2362, The Tau Canis Majoris Cluster
By Rony De Laet

A few months ago, Mark (Novbabies) suggested me to put NGC 2362 on my observing list. The object was unknown to me. The fact that it concerned a rather small open cluster which culminated only a poor 13° above my southern horizon, didn’t excite me at that time. But how wrong was my assumption! The Tau Canis Majoris Cluster turned out to one of the most enjoyable vistas in the sky. The cluster puts the observer to the test. The bright Tau outshines the fainter cluster members nearby. It’s hard to maintain night vision with Tau in the picture. NGC 2362 is a scintillating mix of brighter and fainter stars that swirls around Tau. With averted vision, more spots of unresolved starlight lit up around the cluster. And that’s only my impression with the cluster near horizon. I can only imagine how magnificant the cluster must shine when higher in the sky. Reproducing the cluster on a sketch is another challenge. I’ve made several attemps to try to bring justice to the cluster, but I fell short. I tried to mimic the contrast between the bright Tau Canis Majoris and the swirling group of faint stars around it. I promised myself not to use too much glare on the sketch, but it’s hard to find the right balance. There’s nothing that beats the real thing! So if the sketch pleases you, do try to go out to see the cluster for yourself. You won’t be dissapointed. And thanks Mark for the suggestion in the first place.

Date : February 6, 2008
Time : around 21.30UT
Scope : Skywatcher 102/500
Eyepiece : Hyperion Zoom at 8 mm
Power : x63
FOV: 65′
Filter : none
Seeing : 3/5
Transp. : 2,5/5
Nelm : 4,8
Sketch Orientation : N up, W right.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.

In Search of IC 1318

IC 1318

The Gamma Cygni Starfield
By Rony De Laet

The Gamma Cygni Starfield, in search of IC 1318

Here is a sketch of a crowded milky way starfield. I waited for Gamma Cyngi to reach zenith, in an attempt to glimpse IC1318. I did not know what to expect and centered on Gamma Cygni. I was worried about the amount of stars that would be visible within the field of view. The UHC filter helped in reducing the number of faint stars to be drawn. I spent almost two hours behind the eyepiece. So here is my impression. I don’t know if I succeeded in observing IC 1318, I just represented the luminosity observed with the UHC filter.

Date : October 14, 2007
Time : 21.00UT
Scope : Skywatcher 102/500
TV Plössl 32mm
Power : x16
FOV: 192′
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.