Aquila lacks a Messier object, or any first rate object in general. There are many fine objects, just none that compare to showpieces in many other constellations. Thus on July 21st I tackled the best object in Aquila, in my humble opinion.
oc 6709 ( 15'; V. 6.7 mag.; Br. * 9 mag.; 111 *s) is arguably the finest cluster in Aquila, and likely its finest object (in a 12" scope). I have fond memories of it from Lake Penage with the old Edmund 8" scope, and indeed it looks great in Deb's 6" reflector and in our Edmund Astroscan (4 1/4"). In the 12" it is a minor showpiece, especially to the experienced observer's eye. Two orange stars lie amidst the group, and at higher powers they become double. At 43x and 60x the cluster reminds me of a dreidel. There is a definite "Y" shape to it. I went up to 83x, then on to 100x, 125x, 150x, 187x, and finally 200x, before returning to 60x again. The first orange double precedes the second one, and has a very close, faint companion. The second pair is orange and blue. There is a third, fainter and very close pair sitting very near the second. The cluster has some dense knots, but all is resolved at 200x. I spent a long time here, and also came back several times.
Oc 6724 (3'; V. 10 mag.; Br. * 12 mag.; 10 *s) was new for me. It is a disappointing NGC object, especially after viewing 6709 right next door. 200x shows 8 stars in a tight group, preceding a brighter star. Following that star is yet another faint group. Nothing too special is here.
On the other hand, oc Poole J1855.0+1047 (6'; 40 *s) is marginally better viewing than 6724. It was seen at 60x as a small, very dense knot of somewhat bright stars. It is just north following 6709, and north preceding 6724. It lies just north of a bright triangle of stars that includes V913. Fifteen stars were counted in a small, tight group as viewed at 250x.
NGC oc 6738 (15' V. 8.3 mag.;) appears bright and straggly at 60x, located north preceding a bright double star, and within a triangle of bright stars. This was a new one for me. 100x and 125x show the main group as somewhat circular. Forty stars were counted here, and there is a very faint group following. The many bright stars, including several not part of the cluster make this a decent group to view.
On the night of July 24th, iIt was time for another stellar-like planetary nebula.
I. 4846 (11"; V. 11.9 mag.; Cent. * 15.1 mag.) was confirmed after some searching. I used my Skyglow filter and 250x to do so. It is immediately north of a somewhat bright star, a double with faint companion. Grayish-blue in colour the nebula resembles a very faint star with a tiny surrounding ring of haze. Nothing to see here, folks. It's interesting to note that the second IC catalogue (#1530 onward) was discovered photographically.
It comes as a surprise to some viewers that summer constellations contains galaxies. Last summer I viewed all of the ones in Lyra and Cygnus, a significant number. Galaxies near the brighter portion of the Milky Way are difficult to observe, as they are nearly always placed within a bright star field.
However, eg 6814 (3' x 2'.8: V. 11.2 mag.; SB 13.4 mag.) was easily spotted at 100x, being large and round. It bore magnification well, and I used up to 200x with good results. The central area was bright and large, showing well with the aperture stopped down to 8". Using full aperture, a wide, much fainter haze surrounded it. No central core was visible, though several faint stars are involved. We even saw the galaxy very faintly in the 6" scope. If you are going to see only one galaxy in Aquila, it should be this one. Good luck!
Gc Palomar 11 (10'; V. 9.8) is a bit of a challenge, but not too bad for a 12" in a good sky. It was seen at 60x and observed through 187x. It is essentially a fairly large area of very, very faint stars resolving in behind brighter ones in the foreground. Located south of a magnitude 8.5 star, to me it is like a larger Berkeley cluster. Don't expect to see a "globular cluster."
NGC eg 6821 (1'.1 x 1'.1: V. and SB 13.1) is one of those rare galaxies where the surface brightness and visual magnitude are equal. Located at 100x, it was clearly round, faint, pretty big, and seen best with averted vision. At -7 degrees I was happy to find this one so easily. A very faint star is following.
Two planetary nebulae were next on my observing list.
Pn 6772 (86"; V. 12.7 mag.; Cent. * 18.6 mag.) was a ghostly apparition, spotted at 60x using the Skyglow filter. It was large, possible appearing even larger than M57! I used up to 200x tonight, which shows the nebula to be of uniform brightness and shape (round). Though far from being a showpiece, it was fun to observe this in the 12". Next was:
pn 6778 (37"; V. 12.3; Cent. * 16.9). Less than half the size of nearby 6772, it is considerably brighter and much easier to see. It is medium in size and noted well at 120x with the filter. Very good views were had at 250x, also with the filter. Here it began to appear oval, and 2 brighter knots were glimpsed within. It had a bright, distinct middle section and a small, much fainter outer area. Up to 375x was used here successfully. This is virtually my highest usable magnification. This object is worth a stopover.
The final object in Part 2 (there will be a Part 3) is oc 6775 (13'; 10 *s). While its standing as an actual cluster may be in some doubt, this object does offer an interesting field surrounding it. A small, tight group of stars is noted here. 12 stars were counted at 200x in an area no more than 3' or 4'. Preceding this is a more open group of stars with similar brightness to the first group. Both together make up 6775. Twenty more stars are in the wider group. The cluster can be seen well at 150x. A brighter circlet of stars lies just north.
To be continued...
Mapman Mike
oc 6709 ( 15'; V. 6.7 mag.; Br. * 9 mag.; 111 *s) is arguably the finest cluster in Aquila, and likely its finest object (in a 12" scope). I have fond memories of it from Lake Penage with the old Edmund 8" scope, and indeed it looks great in Deb's 6" reflector and in our Edmund Astroscan (4 1/4"). In the 12" it is a minor showpiece, especially to the experienced observer's eye. Two orange stars lie amidst the group, and at higher powers they become double. At 43x and 60x the cluster reminds me of a dreidel. There is a definite "Y" shape to it. I went up to 83x, then on to 100x, 125x, 150x, 187x, and finally 200x, before returning to 60x again. The first orange double precedes the second one, and has a very close, faint companion. The second pair is orange and blue. There is a third, fainter and very close pair sitting very near the second. The cluster has some dense knots, but all is resolved at 200x. I spent a long time here, and also came back several times.
Oc 6724 (3'; V. 10 mag.; Br. * 12 mag.; 10 *s) was new for me. It is a disappointing NGC object, especially after viewing 6709 right next door. 200x shows 8 stars in a tight group, preceding a brighter star. Following that star is yet another faint group. Nothing too special is here.
On the other hand, oc Poole J1855.0+1047 (6'; 40 *s) is marginally better viewing than 6724. It was seen at 60x as a small, very dense knot of somewhat bright stars. It is just north following 6709, and north preceding 6724. It lies just north of a bright triangle of stars that includes V913. Fifteen stars were counted in a small, tight group as viewed at 250x.
NGC oc 6738 (15' V. 8.3 mag.;) appears bright and straggly at 60x, located north preceding a bright double star, and within a triangle of bright stars. This was a new one for me. 100x and 125x show the main group as somewhat circular. Forty stars were counted here, and there is a very faint group following. The many bright stars, including several not part of the cluster make this a decent group to view.
On the night of July 24th, iIt was time for another stellar-like planetary nebula.
I. 4846 (11"; V. 11.9 mag.; Cent. * 15.1 mag.) was confirmed after some searching. I used my Skyglow filter and 250x to do so. It is immediately north of a somewhat bright star, a double with faint companion. Grayish-blue in colour the nebula resembles a very faint star with a tiny surrounding ring of haze. Nothing to see here, folks. It's interesting to note that the second IC catalogue (#1530 onward) was discovered photographically.
It comes as a surprise to some viewers that summer constellations contains galaxies. Last summer I viewed all of the ones in Lyra and Cygnus, a significant number. Galaxies near the brighter portion of the Milky Way are difficult to observe, as they are nearly always placed within a bright star field.
However, eg 6814 (3' x 2'.8: V. 11.2 mag.; SB 13.4 mag.) was easily spotted at 100x, being large and round. It bore magnification well, and I used up to 200x with good results. The central area was bright and large, showing well with the aperture stopped down to 8". Using full aperture, a wide, much fainter haze surrounded it. No central core was visible, though several faint stars are involved. We even saw the galaxy very faintly in the 6" scope. If you are going to see only one galaxy in Aquila, it should be this one. Good luck!
Gc Palomar 11 (10'; V. 9.8) is a bit of a challenge, but not too bad for a 12" in a good sky. It was seen at 60x and observed through 187x. It is essentially a fairly large area of very, very faint stars resolving in behind brighter ones in the foreground. Located south of a magnitude 8.5 star, to me it is like a larger Berkeley cluster. Don't expect to see a "globular cluster."
NGC eg 6821 (1'.1 x 1'.1: V. and SB 13.1) is one of those rare galaxies where the surface brightness and visual magnitude are equal. Located at 100x, it was clearly round, faint, pretty big, and seen best with averted vision. At -7 degrees I was happy to find this one so easily. A very faint star is following.
Two planetary nebulae were next on my observing list.
Pn 6772 (86"; V. 12.7 mag.; Cent. * 18.6 mag.) was a ghostly apparition, spotted at 60x using the Skyglow filter. It was large, possible appearing even larger than M57! I used up to 200x tonight, which shows the nebula to be of uniform brightness and shape (round). Though far from being a showpiece, it was fun to observe this in the 12". Next was:
pn 6778 (37"; V. 12.3; Cent. * 16.9). Less than half the size of nearby 6772, it is considerably brighter and much easier to see. It is medium in size and noted well at 120x with the filter. Very good views were had at 250x, also with the filter. Here it began to appear oval, and 2 brighter knots were glimpsed within. It had a bright, distinct middle section and a small, much fainter outer area. Up to 375x was used here successfully. This is virtually my highest usable magnification. This object is worth a stopover.
The final object in Part 2 (there will be a Part 3) is oc 6775 (13'; 10 *s). While its standing as an actual cluster may be in some doubt, this object does offer an interesting field surrounding it. A small, tight group of stars is noted here. 12 stars were counted at 200x in an area no more than 3' or 4'. Preceding this is a more open group of stars with similar brightness to the first group. Both together make up 6775. Twenty more stars are in the wider group. The cluster can be seen well at 150x. A brighter circlet of stars lies just north.
To be continued...
Mapman Mike
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