I began official studies of Sagittarius on the night of July 23rd, 2014, and capped it off on September 15th, 2015! I had observed it in detail with the Edmund 8", but this time around I was after ALL of the NGC within my reach. There are a few southern galaxies that I could not reach; they will have to wait for a more southerly viewing location. This constellation is stacked with fabulous objects, including many Messier objects. It is particularly rich in open and globular clusters, as well as nebula. I will discuss each NGC object in some detail, using my notes as reference. The objects may not appear in numerical order at first--hopefully they will when this massive blogging project about Sagittarius is done.
These are my observations from summer of 2014:
These are my observations from summer of 2014:
gc 6440: 4'.4; Vis. mag. 9.3; Br. * mag. 16.7: Spotted easily at 60x, this bright globular had a very bright center, with a large area of surrounding haze. Like 6760 in Aquila, it seemed to glow like a lamp, though no stars resolved here. The first of 21 NGC globular clusters that I observed in Sagittarius.
http://www.ngcicproject.org/dss/n/6/n6440.jpg
pn 6445: 44"; Vis. mag. 11.2; Cent. * mag. 19: Nick named "Little Gem," it was spotted at 60x, though seen much better with the Skyglow filter. It was large and faint. Though close to a bright 7.5 mag. star, a very faint one lay just north. This end of the nebula seems brighter, almost as if another very faint star were here.
pn 6445, "Little Gem"
http://www.lex.sk.ca/astro/DeepSky/NGC6445_220.jpg
oc 6469: 8'; Vis. mag. 7.6; Br. * Mag. 9; 60 *s: Located at 60x, this is a widely scattered group with two bright stars in the middle. Both are doubles, with the brightest being a wider pair seen well at 125x, and the other with a much closer and fainter companion. 25-30 stars were brighter ones, with several fainter stars also in attendance. There are also two faint groups just preceding the main group.
http://www.ngcicproject.org/dss/n/6/n6469.jpg
oc 6476: 20': Now listed as a star cloud, it was not unlike a large, loose Collinder cluster. 60x gave the best view, showing more than 50 stars, bright, with an unresolved milky cloud in behind. The entire area is rich for casual sweeping.
http://www.ngcicproject.org/dss/n/6/n6476.jpg
oc 6494--Messier 23: 25'; Vis. 5.5; Br. * mag. 10; 150 *s: I don't know what I was expecting, but it wasn't this cluster, certainly one of the finest in the heavens and a major showpiece! Observed mainly at 43x (2" eyepiece), 60x and 83x, there are many bright stars, seemingly in loose chains, crescents and lines curved and straight. There are too many stars to count in a 12" mirror. There is a dense knot following, and a bright white star north preceding (mag. 6.5). A line of stars connects the cluster to this star! Best for me at 83x, where it fully resolves and just fits into the field. At least 100 stars appear to be bright ones, with nearly as many being much fainter. It resembles a city seen at night from an aircraft. Highly recommended! I returned on many occasions for another look.
http://www.ngcicproject.org/dss/n/6/n6494.jpg
oc 6507: 15'; Vis. 9.9; Br. * mag. 12; 35*s: Lying just north of Messier 23, this was a new cluster for me. It was spotted in a somewhat milky sky at 60x. WX is a 9.6 mag. star lying near the center. 100x and 125x show a large sprinkling of faint stars, with many of them following WX, which is yellow. About 30 stars were counted tonight, and I used up to 187x with success. I also observed it at 100x with the mirror stopped down to 8". Here, the stars were very faint. However, it is a pretty decent object in a 12" mirror.
http://www.ngcicproject.org/dss/n/6/n6507.jpg
oc 6520: 5'; Vis. 7.6; Br. * mag. 9; 60*s: The cluster is small, but lovely and intense at 60x. A bright orange star sits in the very center, and 9 more relatively bright stars are seen. Resolution of fainter members is good at 100x. It was viewed up to 200x, where 20 faint stars immediately circling the center star were noted. About 30 others surrounded this inner group. A recommended object, this is a favourite of mine, especially when combined with the amazing Barnard 86 dark nebula right next door!
oc 6520 and Barnard 86
http://coldspringobservatory.org
gc 6522: 9'.4; vis. 9.9; Br. * 14.1: 60x shows the globular very well, along with nearby gc 6528. The pair make a fine contrast, with 6522 much larger and brighter. 100x shows it with a bright core surrounded by a much larger amount of fainter haze. One star resolves, closely following the core. Up to 200x resolves half a dozen stars, with the core shrinking and becoming lumpy. More resolution might occur if the object was viewed earlier in the evening, or earlier in the season. (Sept. 14th/14 observation).
gc 6528: 5'; Vis. 9.6; Br. * mag. 15.5: Viewed early tonight (Sept. 16th/14), it and 6522 were both seen much better! Though similar in size to its companion, the core here is dimmer. One star lies near the core, but about 8 stars resolve at 125x-200x. The core shows no detail, unlike 6522,which seems to have a dark break in the center. Only outlier stars resolved tonight.
gc 6540: 1'.5; Vis. 14.6: An oddball globular, called an open cluster on my push-to screen. Spotted at 60x, it was very faint at 8" of aperture. It is an easy hop from oc 6520, with a lovely orange and blue double star between. 100x resolves a few very faint stars amidst a slightly arcing linear haze. Up to 300x was used to resolve about 10 stars, with haze and or nebula in behind. Reminiscent of what a very faint M 71 would look like.
pn 6565: 14"; Vis. 11.6; Cent. * mag. 18.5: Located at
100x and confirmed at 120x with the Skyglow filter. It was tiny and
round, but really bright. 250x gave satisfactory views, showing it
clearly amongst a group of 4 very faint stars.
pn 6567: 12"; Vis. 11; Cent. * mag. 14.3: Virtually stellar, even at 250x, where some fuzziness shows, and a grayish-blue colour. It was very bright, though.
gn 6589: 5' x 3'; Reflection: Both objects are within the confines of oc Cr. 371 (see separate page
oc 6603: 4'; Vis. 11.1; Br. * mag. 14; 100 *s: At 43x the cluster is hazy, bright, and pretty big. It looks so much like a comet that I wonder if this is the true M 24 (see IC 4715 on the IC page). However, even at 43x it begins to resolve. We also resolved some of it in the 6" Star Blaster at 125x. At 60x it is still bright, and just beginning to resolve. At 100x there is some resolution all across it, like a globular. A bright line of haze runs through the middle, NE to SW. 125x gives good resolution, with that central bar of haze narrowing. The cluster is fully resolved at 250x, including the bar, now seen as a line of faint stars. There are dark patches on either side of this line, as well as myriad stars. A real beauty in a 12"!
pn 6620: 8"; Vis. 12.7; Cent. * mag. 19.6: Even at 250x with the filter on, this object was just beyond the "Stellar" category. Unmistakable though, and near a star of similar magnitude.
gc 6626--M 28: 13'.8; Vis. 6.9; Br. * mag. 12: Viewed quite late in the evening (Sept. 17th/14), this globular cluster is a veritable lighthouse at 60x. It was granular until 100x, when it began to resolve nicely. 125x resolves stars into the core. I had leisurely views at 187x, 200x, and especially 250x, where an uncountable number of stars resolved. The core breaks up at this power, with a few tiny points of light resolving. A showpiece object in a 12" mirror!
pn 6629: 16"; Vis. 11.3; Cent. * mag. 12.9: Confirmed at 120x with the Skyglow filter. It is small, round, bright and quite easy to i.d. 250x shows a compact, round haze surrounding a mag. 13 star.
gc 6638: 7'.3; Vis. 9.2; Br. * mag. 14.2: Big and bright at 60x, and at 100x a few outliers are resolved. At 150x the blazing core appears lumpy. At 187x the core is flaring outwards. At 200x-250x fair resolution is obtained, with a few stars noticed very close to the core. About a dozen stars were resolved.
gc 6642: 5'.8; Vis. 8.9: At 60x the cluster is decently large, and medium bright. A bright star is just north. To my surprise a few outliers resolve. Resolution becomes fair at 125x, and at 150x it becomes good, with a few stars resolving to the core! A pair of double stars north preceding are split at 187x. Each primary star has a very faint, close companion some distance away (30" to 35"?). there is good resolution at 187x, 200x and 250x, where two stars resolve in the very center. A nice warm-up for what was to follow (gc 6656--M22).
pn 6644: 12" Vis. 10.7; Cent. * mag. 15.6: Very bright object, but nearly stellar, even at 250x with the filter. It was seen as a very slight blue fuzz, round.
gc 6656--Messier 22: 32'; Vis. 5.2; Br. * mag. 10.7: At 60x this monstrously sized globular cluster is already resolving all across its face, and the core is large and extremely bright. 100x gives a dazzling view, and the core has dark cracks running through it. Though there is still plenty of unresolved haze, there are already over 100 stars showing. 125x begins to show deep into the cluster, with stars popping everywhere. From 187x and up it is like a fireworks explosion! At 200x a small, dense knot of stars resolves just following the center. 250x, 300x and 375x all resolve more and more stars, with less and less haze. The effect is overwhelming in a 12" mirror!
pn I. 4673: 15"; Vis. 13; Cent. * mag. 17.6: The nebula was ghostly and round at 187x with the Skyglow filter. 200x with no filter also showed it distinctly. It was best at 250x with the filter; however, more faint stars were seen without it.
oc I. 4715--Messier 24: 120': My 2" eyepiece at 43x was the best tool for the job! I began my sweep with a field of 6 bright stars, arrow-shaped, immediately south of oc 6603 (see above). This seems to be the most splendid and rich area, and appears to be the heart of the star cloud. The sweeping is especially fine, wonderfully so south preceding V4387. This yellow star leads south to another incredible area of nearly infinite numbers and layers of stars. Back at the original arrowhead, the star just south of oc 6603 is deep orange. South following is a bright double star, yellow and blue, which make a fine pair. Take some time and just drive around.
oc I. 4725--Messier 25: 26'; Vis. 4.6; Br. * mag. 8; 600 *s: This is an eye-popping cluster in the 12", rich in bright stars beyond counting. Mostly resolved at 60x, but also stunning at 83x and 100x. There seems to be a fair number of orange stars, including U, V3508, and another bright one immediately following U. Though there is density to the central area as well as a few other conspicuous pockets, the cluster is widely scattered for the most part. Because of the several colourful stars and so many bright ones, M 25 is suitable for any size aperture. There are lines and patterns galore. I spent a long time observing here. The cluster is surrounded by impressive Milky Way star fields, with an especially interesting dense knot just following. A cluster to return to often!
pn I. 4732: 13"; Vis. 12.1; Cent. * mag. 16.2: I am becoming more skilled at identifying very small planetaries. There were several again tonight (Sept. 22/14). At 60x with a Skyglow filter it was bluish, fuzzy and bright. 250x with the filter showed it as small, round, and still quite bright. Up to 375x was applied, and while bright, it was still just beyond stellar.
Observations from the summer of 2015 will appear in Part 2. Clear skies!
Mapman Mike
http://www.ngcicproject.org/dss/n/6/n6522.jpg
gc 6528: 5'; Vis. 9.6; Br. * mag. 15.5: Viewed early tonight (Sept. 16th/14), it and 6522 were both seen much better! Though similar in size to its companion, the core here is dimmer. One star lies near the core, but about 8 stars resolve at 125x-200x. The core shows no detail, unlike 6522,which seems to have a dark break in the center. Only outlier stars resolved tonight.
http://www.ngcicproject.org/dss/n/6/n6528.jpg
gc 6540: 1'.5; Vis. 14.6: An oddball globular, called an open cluster on my push-to screen. Spotted at 60x, it was very faint at 8" of aperture. It is an easy hop from oc 6520, with a lovely orange and blue double star between. 100x resolves a few very faint stars amidst a slightly arcing linear haze. Up to 300x was used to resolve about 10 stars, with haze and or nebula in behind. Reminiscent of what a very faint M 71 would look like.
gc 6540
http://spider.seds.org/spider/MWGC/Dss/n6540d15.jpg
http://www.ngcicproject.org/dss/n/6/n6565.jpg
pn 6567: 12"; Vis. 11; Cent. * mag. 14.3: Virtually stellar, even at 250x, where some fuzziness shows, and a grayish-blue colour. It was very bright, though.
http://www.ngcicproject.org/dss/n/6/n6567.jpg
gn 6590: 4' x 3'; Reflection: on "Objects from Other Catalogues"), in the south preceding quadrant. However, most of the cluster is closer to a
bright star in the north section. 6589 is fainter than 6590, seen as a
hazy patch following a bright star, which has a very faint companion.
6590 is impressive even at higher powers, seen as a bright hazy patch
involved with a pair of faint stars. The Skyglow filter actually helped
a bit, probably by dimming the brighter stars. Along with the
Collinder cluster, this makes a fun little stopover with a 12".
pn 6589, bottom; pn 6590, top
http://www.anysllum.com/Seleccioweb20130615/NGC_6590_NGC_6589_50secX12_20130615.jpg
oc 6603: 4'; Vis. 11.1; Br. * mag. 14; 100 *s: At 43x the cluster is hazy, bright, and pretty big. It looks so much like a comet that I wonder if this is the true M 24 (see IC 4715 on the IC page). However, even at 43x it begins to resolve. We also resolved some of it in the 6" Star Blaster at 125x. At 60x it is still bright, and just beginning to resolve. At 100x there is some resolution all across it, like a globular. A bright line of haze runs through the middle, NE to SW. 125x gives good resolution, with that central bar of haze narrowing. The cluster is fully resolved at 250x, including the bar, now seen as a line of faint stars. There are dark patches on either side of this line, as well as myriad stars. A real beauty in a 12"!
oc 6603, deep within M 24
https://sunnymeade.files.wordpress.com/2015/04/ngc-6603-cropped.jpg
pn 6620: 8"; Vis. 12.7; Cent. * mag. 19.6: Even at 250x with the filter on, this object was just beyond the "Stellar" category. Unmistakable though, and near a star of similar magnitude.
http://www.ngcicproject.org/dss/n/6/n6620.jpg
gc 6626--M 28: 13'.8; Vis. 6.9; Br. * mag. 12: Viewed quite late in the evening (Sept. 17th/14), this globular cluster is a veritable lighthouse at 60x. It was granular until 100x, when it began to resolve nicely. 125x resolves stars into the core. I had leisurely views at 187x, 200x, and especially 250x, where an uncountable number of stars resolved. The core breaks up at this power, with a few tiny points of light resolving. A showpiece object in a 12" mirror!
http://www.ngcicproject.org/dss/n/6/n6626.jpg
pn 6629: 16"; Vis. 11.3; Cent. * mag. 12.9: Confirmed at 120x with the Skyglow filter. It is small, round, bright and quite easy to i.d. 250x shows a compact, round haze surrounding a mag. 13 star.
http://www.ngcicproject.org/dss/n/6/n6629.jpg
gc 6638: 7'.3; Vis. 9.2; Br. * mag. 14.2: Big and bright at 60x, and at 100x a few outliers are resolved. At 150x the blazing core appears lumpy. At 187x the core is flaring outwards. At 200x-250x fair resolution is obtained, with a few stars noticed very close to the core. About a dozen stars were resolved.
http://www.ngcicproject.org/dss/n/6/n6638.jpg
gc 6642: 5'.8; Vis. 8.9: At 60x the cluster is decently large, and medium bright. A bright star is just north. To my surprise a few outliers resolve. Resolution becomes fair at 125x, and at 150x it becomes good, with a few stars resolving to the core! A pair of double stars north preceding are split at 187x. Each primary star has a very faint, close companion some distance away (30" to 35"?). there is good resolution at 187x, 200x and 250x, where two stars resolve in the very center. A nice warm-up for what was to follow (gc 6656--M22).
http://www.ngcicproject.org/dss/n/6/n6642.jpg
pn 6644: 12" Vis. 10.7; Cent. * mag. 15.6: Very bright object, but nearly stellar, even at 250x with the filter. It was seen as a very slight blue fuzz, round.
http://www.ngcicproject.org/dss/n/6/n6644.jpg
gc 6656--Messier 22: 32'; Vis. 5.2; Br. * mag. 10.7: At 60x this monstrously sized globular cluster is already resolving all across its face, and the core is large and extremely bright. 100x gives a dazzling view, and the core has dark cracks running through it. Though there is still plenty of unresolved haze, there are already over 100 stars showing. 125x begins to show deep into the cluster, with stars popping everywhere. From 187x and up it is like a fireworks explosion! At 200x a small, dense knot of stars resolves just following the center. 250x, 300x and 375x all resolve more and more stars, with less and less haze. The effect is overwhelming in a 12" mirror!
http://www.ngcicproject.org/dss/n/6/n6656.jpg
pn I. 4673: 15"; Vis. 13; Cent. * mag. 17.6: The nebula was ghostly and round at 187x with the Skyglow filter. 200x with no filter also showed it distinctly. It was best at 250x with the filter; however, more faint stars were seen without it.
http://cseligman.com/text/atlas/ic46a.htm#ic4673
http://cseligman.com/text/atlas/ic47.htm#ic4715
oc I. 4725--Messier 25: 26'; Vis. 4.6; Br. * mag. 8; 600 *s: This is an eye-popping cluster in the 12", rich in bright stars beyond counting. Mostly resolved at 60x, but also stunning at 83x and 100x. There seems to be a fair number of orange stars, including U, V3508, and another bright one immediately following U. Though there is density to the central area as well as a few other conspicuous pockets, the cluster is widely scattered for the most part. Because of the several colourful stars and so many bright ones, M 25 is suitable for any size aperture. There are lines and patterns galore. I spent a long time observing here. The cluster is surrounded by impressive Milky Way star fields, with an especially interesting dense knot just following. A cluster to return to often!
http://cseligman.com/text/atlas/ic47.htm#ic4715
pn I. 4732: 13"; Vis. 12.1; Cent. * mag. 16.2: I am becoming more skilled at identifying very small planetaries. There were several again tonight (Sept. 22/14). At 60x with a Skyglow filter it was bluish, fuzzy and bright. 250x with the filter showed it as small, round, and still quite bright. Up to 375x was applied, and while bright, it was still just beyond stellar.
http://cseligman.com/text/atlas/ic47.htm#ic4715
Observations from the summer of 2015 will appear in Part 2. Clear skies!
Mapman Mike
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