To get a quick look at what Sagitta has to offer, see my blog entry for July 27th, 2014. All objects listed there are covered here in detail, except for double stars. I covered about half of the objects on the night of September 22nd. The constellation highlight is M 71, a globular cluster that resolves well in a 12" mirror. However, there are a few minor gems, too.
pn 6886 (10"; V. 11.4 mag.; Cent. * 18 mag.) was identified at 120x with a Skyglow filter. 200x and 250x show it as bluish in color, and bright, with a very small circular disc. It is accompanied by two bright stars, each one a double with a faint companion in opposing position angles.
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pn I. 4997 (13"; V. 10.5 mag.; Cent. * 14.4 mag.) was also identified at 120x with the filter. It was the northernmost of two bright stars. It was slightly bluish. It was very bright at 250x. The central star could not be seen clearly due to the brightness of the nebula, which is slightly larger than stellar.
pn 6879 (9"; V. 12.5; Cent. * 14.8) was identified at 120x using the Skyglow filter. At 200x and 250x it shows a tiny, fairly bright disc. The central star is seen steadily at 250x without difficulty.
http://www.ngcicproject.org
oc 6839 (4'; 12 *s) was new for me. It is listed as an asterism (a chance lining up of stars). Even so, I saw 15 stars at 100x, preceding a lovely bright star chain. The brightest four members resemble an asterism, but some are double. Adding on a faint group in the south end adds up to an open cluster in my estimation, though a minor one.
http://www.ngcicproject.org
oc Harvard 20 (8'; V. 7.7; Br. * 8.9 mag.; 28 *s) is mostly resolved at 60x. It was quite lovely at 100x, with two bright stars involved. At 125x 35 stars were counted, several very faint. Members are fairly scattered. It appears in a low power field with M 71.
gc 6838--Messier 71 (7'.2; V. 8.4; Br. * 12.1) already is resolving well at 43x. Oc Harvard 20 is in the same field, south. At 60x the globular cluster's center seems offset, south preceding. 100x shows resolution all across the object, plus some core detail. At 125x the south preceding side is brighter, with the north following side darker (though still busy with stars). 187x shows dozens of stars, along with plenty of core detail. The cluster now appears elongated. I went as high as 375x, almost resolving the entire cluster! Only a tiny bit of core haze remains! This is a great object in a 12" mirror, and it appeared outstanding at all magnification ranges.
I completed work in Sagitta on September 24th. I was unable to locate gc Pal 10. Four small clusters finished up my work here.
oc Ro 1 (3'; 15*s) was located at 60x. 100x shows three bright stars leading into a hazy center. At 150x the 3-star chain expands to 6, several of them double. 187x shows 15 stars in a very tight group.
oc Ro 3 (5'; 20*s) was a circlet of 9 stars at first, including four in a tight knot. Only two stars could be seen in the dark center. 187x shows about 25 stars, including faint companions to a few of the brighter members. The north one is multiple.
oc Be 44 (2'; Br. * 16 mag.; 30*s) was located at 125x. It was a small, faint hazy patch preceding two very faint stars. There is not much to see here in a 12" mirror.
oc Be 47 (3'; Br. * 16 mag.; 20*s) was observed at 200x as a tiny, faint haze near a triangle of faint stars, all preceding a bright star (mag. 9.5).
These six recent blog entries describe my major summer work in Aquila, Delphinus and Sagitta. Last year I completed work in Lyra and Cygnus. Work in Sagittarius has begun, but may take all of next summer to complete. I am also working in Pegasus, Perseus, Cetus, Cepheus, Lepus, Monoceros, Leo and Bootes. When each is completed, I shall report my findings here. Cassiopeia was recently concluded, and will likely form the next major segment of the blog. Cepheus is nearly done; two good nights in November should see me complete studies there.
Mapman Mike
http://www.ngcicproject.org
I completed work in Sagitta on September 24th. I was unable to locate gc Pal 10. Four small clusters finished up my work here.
oc Ro 1 (3'; 15*s) was located at 60x. 100x shows three bright stars leading into a hazy center. At 150x the 3-star chain expands to 6, several of them double. 187x shows 15 stars in a very tight group.
oc Ro 3 (5'; 20*s) was a circlet of 9 stars at first, including four in a tight knot. Only two stars could be seen in the dark center. 187x shows about 25 stars, including faint companions to a few of the brighter members. The north one is multiple.
oc Be 44 (2'; Br. * 16 mag.; 30*s) was located at 125x. It was a small, faint hazy patch preceding two very faint stars. There is not much to see here in a 12" mirror.
oc Be 47 (3'; Br. * 16 mag.; 20*s) was observed at 200x as a tiny, faint haze near a triangle of faint stars, all preceding a bright star (mag. 9.5).
These six recent blog entries describe my major summer work in Aquila, Delphinus and Sagitta. Last year I completed work in Lyra and Cygnus. Work in Sagittarius has begun, but may take all of next summer to complete. I am also working in Pegasus, Perseus, Cetus, Cepheus, Lepus, Monoceros, Leo and Bootes. When each is completed, I shall report my findings here. Cassiopeia was recently concluded, and will likely form the next major segment of the blog. Cepheus is nearly done; two good nights in November should see me complete studies there.
Mapman Mike
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