I have stopped observing in Leo for this year, as it is getting into unfavourable skies for me. I am hoping to eventually observe all 364 NGC objects in the constellation, and in two seasons of observing I have managed to view 64 of them! Only 300 more left to see.
In the all-sky edition of Unranometria is a closeup chart of a galaxy-rich area in Leo. Chart A-11 is a pinpoint view of a tiny section of main chart 72, left page. Last year I only managed to view one galaxy within chart A-11, and it was just outside the Abell 1367 boundary. This year I completed observing the galaxies within the chart, viewing all of the NGC objects, as well as the lone IC galaxy. I even threw in a few UGC galaxies, as they were brighter than some of the NGC ones. It took several nights with exceptional skies.
Once you know your way around Abell 1367, you can view all of the objects easily in a very short time, kind of like a mini-Messier marathon. However, initially it takes a long time to properly identify which galaxy is which. Most are faint, and well beyond 12th mag. I consider anything with a visual mag. of 12.5 or brighter to be an easy object for a 12" scope in a good sky. 12.5 to mag. 13 is considered more difficult, but a reasonable target. Mag. 13 to 13.5 requires good seeing and some patience, as well as higher magnifications. 13.5 to 14 can be considered difficult objects, especially if somewhat large, or if edge-on. Below mag. 14 really requires an expert eye and pinpoint accuracy, and thus the close up chart becomes very valuable.
Tackling a project such as Abell 1367 is an excellent way to challenge yourself (with a 12"-14"), and offers a chance to spot very faint objects that might be harder to locate otherwise. If you have never had much success with very faint objects, this might be a good place to try some.
I will first discuss the objects that lie just outside the boundary of Abell 1367, and then proceed to the actual galaxy cluster itself. Once within the cluster, I always begin with a bright galaxy that is easy to identify, and then star and galaxy hop from there.
Uranometria 2000, Chart A-11, showing galaxies in and around A 1367 that I observed.
V.= Visual magnitude.
sb= surface brightness
eg 3805: 1'.4 x 1'.1: V. 12.7; sb 13.2: Preceding the main group, this was my first target and easy to spot. Quite dim. Viewed in 2013. All others viewed in 2014.
http://www.ngcicproject.org/dss/n/3/n3805.jpg
eg 3787: 0'.4 x 0'.3: V. 13.7; sb 12.1: Located at 200x, where it was round and tiny. Moon was up, too (5.5 days old!).
http://www.ngcicproject.org/dss/n/3/n3787.jpg
eg 3827: 0'.9 x 0'.8: V. 13.3; sb 12.6: Located at 60x, though faint. Image improves up to 200x. Averted vision shows a larger object than with direct; round with a bright middle.
http://www.ngcicproject.org/dss/n/3/n3787.jpg
UGC eg 6670: 2'.8 x 0'.8: V. 12.9; sb 13.6: Located at 100x, and viewed well up to 200x. Very oval, relatively bright and quite large. Within a bright star field, it lies between 2 stars, mag. 11 and 11.5.
eg 3883: 2'.8 x 2'.3: V. 12.6; sb 14.5: Don't let the 12.6 fool you--this one is quite dim. Located at 100x, it was large and slightly oval.
http://www.ngcicproject.org/dss/n/3/n3883.jpg
eg 3910: 1'.6 x 1'.2: V 13.1; sb 13.9: Spotted easily at 100x, it has a faint star very near, north. Up to 200x was used to see the oval shape. Quite bright overall, with a bright middle.
http://www.ngcicproject.org/dss/n/3/n3910.jpg
ABELL 1367
eg 3884: 2'.1 x 1'.4: V. 12.6; sb 13.7: Located at 100x, it was bright enough though dimmed by a nearby 7 mag. star. Very elliptical. 125x and 150x showed a bright center, sometimes appearing star-like.
http://www.ngcicproject.org/dss/n/3/n3884.jpg
UGC eg 6725: 1'.2 x 0'.7: V. 12.9; sb 12.6: Confirmed sighting at 125x, the galaxy had a stellar nucleus. Oval and much dimmer than 3884. Best with averted vision.
UGC eg 6719: 1'.1 0'.7: V. 13.6; sb 13.2: Located at 100x, it was much easier to see than U6725! Bright and oval at 125x.
eg 3886: 1'.2 x 0'.9: V. 13.2; sb 13.4: An easy object at 100x, and it remains bright up to 200x, even with direct vision. Oval shape unconfirmed. North preceding two faint stars, mag. 11.5 and 11, in a line with it.
http://www.ngcicproject.org/dss/n/3/n3886.jpg
eg 3861: 2'.4 x 1'.5: V. 12.7; sb 13.7: Seen at 100x, and on up to 200x. Not large, but elongation is easy to see. Best with averted vision, as there is a relatively bright star in the field.
http://www.ngcicproject.org/dss/n/3/n3861.jpg
eg 3873: 1'.1 x 1': V. 12.9; sb 13.7: These two galaxies became favourites of mine, and I
eg 3875: 1'.3 x 0'.3: V. 13.7; sb 12.3) observed them over many nights. Located at 100x, the very close pair at first appeared as one larger elongated haze. However, at 125x, 150x, 187x and 200x the object clearly showed two bright centers, especially with averted vision. 3873 was the brighter of the pair, and round. 3875 appeared fainter, smaller and noticeably elongated. Though definitely seen as two close galaxies, at times it did appear as one larger, unusual object.
http://www.ngcicproject.org/dss/n/3/n3873.jpg
eg 3860: 1'.3 x 0'.7: V. 13.4; sb 12.7: This object proved tricky at first, but posed no problem on a superior night. Oval, faint but not difficult. Lies opposite eg 3873 and 75, with a pair of 11 mag. stars between.
http://www.ngcicproject.org/dss/n/3/n3860.jpg
eg 3842: 1'.2 x 1': V. 11.8; sb 12.2: The brightest galaxy on the chart, and the home base for many other fainter galaxies. Makes a nice triplet with 3837 and 3841. Located easily just south preceding a mag. 11 star, one of 4 in a line running NE to SW. Just slightly oval at 200x, and still very bright.
http://www.ngcicproject.org/dss/n/3/n3842.jpg
eg 3841: 0'.9 x 0'.4: V. 13.8; sb 12.5: Much fainter than eg 3842, and elongated. Makes a close triangle with 3842 and the 11 mag. star. Shows well at 187x with 3842.
eg 3837: 1' x 0'.9: V. 13.3; sb 12.9: Easy to locate south following 3842, though not nearly as bright. 3841, 42 and 37 all fit nicely at 125x. Round. Near the 2nd star in a 4-star chain.
eg 3845: 0'.8 x 0'.3: V. 14.2; sb 12.5: A very faint slash was seen at 100x, and seen with averted vision up to 150x. Just north of 3842 and 3841, and north preceding that 11 mag. star.
eg 3844: 1'.7 x 0'.3: V. 14; sb 12.6: Large and oval, though occasionally glimpsed with averted vision as a long slash. Not that difficult!
http://www.ngcicproject.org/dss/n/3/n3844.jpg
eg 3840: 1'.2 x 0'.8: V. 13.7; sb 13.4: Actually quite small and nearly stellar. More difficult than it would seem. Round with averted vision.
eg 3851: 0'.3 x 0'.3: V. 14.7; sb 13.2: Located opposite the 11 mag. star in relation to 3841. Found at 100x, it was nearly stellar, round and fuzzy.
eg UGC 6697: 1'.5 x 0'.3: V. 13.6: sb 12.6: Located at 187x without much difficulty, just preceding 3842. Oval.
eg I. 2951: 1'.4 x 0'.7: V. 13.6; sb 13.7: Follow the line of 11 mag. stars from 3842 SW. Just south preceding the third star is this faint galaxy, nearly attached to an even fainter star. Very faint but not difficult. Possible stellar core at 200x.
eg 3862: 1'.6 x 1'.6: V. 12.7; sb 13.7: A large galaxy with a bright middle, much easier to locate
eg I. 2955: 0'.4 x 0'.3: V. 14.1; sb 13.7) than most other Abell 1367 objects. Noticed at 100x and also observed well at 125x and 150x. At 187x the galaxy began to appear suspicious, as if quite elongated! 200x and averted vision showed 2 galaxies! I. 2955 is almost adjacent, and not plotted on Uranometria. A fun discovery!
http://www.ngcicproject.org/dss/n/3/n3862.jpg
eg 3857: 1'.4 x 0'.7: V. 14.1; sb 13.4: Seen with averted vision at 100x and 125x. It appeared round. Mag. 8.5 star hampers the view.
eg 3859: 1'.2 x 0'.3: V. 14.1; sb 12.8: Though spotted at 100x and 125x, the same 8.5 mag star as in 3857 interferes with viewing. The star, 3857 and this galaxy make an equilateral triangle. At 150x and 187x, the galaxy is large and oval.
http://www.ngcicproject.org/dss/n/3/n3859.jpg
eg 3868: 0'.8 x 0'.3: V. 14.4; sb 12.7: 68 appeared pretty large, though faint. 68 and 67 are
eg 3867: 1'.5 x 0'.6: V. 13.3; sb 13) elliptical with averted vision. 200x shows both galaxies quite
eg 3864: 0'.9 x 0'.7: V. 14.8; sb 14.1) well. 64 is very faint and round, likely the most difficult member of the Abell 1367 NGC.
http://www.ngcicproject.org/dss/n/3/n3867.jpg
eg 3821: 1'.6 x 1'.4: V. 12.8; sb 13.3: Located at 100x and also viewed at 200x. Not difficult to locate. The center had two bright spots, likely a bright core and a foreground star.
http://www.ngcicproject.org/dss/n/3/n3821.jpg
eg 3816: 1'.9 x 1'.1: V. 12.5; sb 13.2: First located at 100x, but afterwards seen as a faint elongated slash at 60x. At 100x and 125x it was bright and quite elongated, with a bright middle and a large amount of fainter outer haze. Quite a decent object, one of the brightest members of Abell 1367.
http://www.ngcicproject.org/dss/n/3/n3816.jpg
There you have it! I really enjoyed my visit to this remarkable area, and will return to it next season for another long look.
Mapman Mike
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