Over five nights this summer, I spent about 19 hours re-observing Lyra. This was my fourth in-depth visit since first encountering the constellation back in 1971. This time, equipped with a 12" Dob, I went really deep in an effort to view every single NGC object within its boundaries. I managed to snag 28 out of 30, likely requiring a darker sky or better eyes to nab the final two. In Part 1, I discussed my encounter with the clusters and nebula of Lyra, including 1 non-NGC object. This time I will discuss the NGC galaxies. There are 27 of them, of which 25 were successfully located and observed. Despite the wealth of double stars in Lyra, most of which I have observed, they will not be discussed at this time. I am now planning Part 3 to deal with them.
Before setting out on our exploration of faint galaxies, a few ground rules must be laid out. Before observing, I have the following information at hand in my field notes: size of object, including length and width, and the visual magnitude and surface brightness of the object (see my earlier essay on mag.). To simplify matters, I combine the visual magnitude with the surface brightness, thus: if a galaxy is assigned a visual mag. 11 and has a surface brightness of 13, then I list the apparent magnitude as 12, simply splitting the difference. This generally works pretty well in the field, and if not completely accurate at least it provides a basis for comparison between the galaxies. However, if things are the other way around (visual 13 and surface brightness 11), things don't work out quite so well. In this case, the true answer usually lies much closer to the visual side of things. While my 12" mirror barely showed some of these objects, perhaps in a very dark, dry sky a smaller mirror would accomplish just as much.
I will begin by listing and very briefly discussing the Lyra galaxies in order of brightness. Note that there are no showpiece galaxies here, though there are a few of significant interest. After the top 3, there are no more with a combined magnitude of less than 13!
6703: 2'.7 x 2'.5--Mag. 12.35: A veritable beacon of light compared to most other galaxies in Lyra! The only galaxy I saw previously, using my Edmund 8". In the same 150x field with 6702. Though bright, it is not all that interesting. In a lovely star field.
6702: 1.'9 x 1'.5--Mag. 12.9: Useful as a comparison with 6703, the 2nd brightest galaxy in Lyra is getting pretty faint! In the same field with 6703. More oval than 6703.
6675: 1'.8 x 1'.3--Mag. 12.9: I could also see this one with the mirror stopped down to 8".
6646: 1'.6 x 1'.3--Mag. 13: A significant number of the galaxies are within easy star hop of Vega. This was the first galaxy in Lyra I saw this year, thus it is one of my favourites. There are two IC galaxies very close by, one easy and one not.
6792: 2'.2 x 1'.3--Mag. 13: Takes high power well, and at 200x it was still pretty bright, quite large, and very elongated. Two 14 mag. stars at the N end.
6688: 1'.6 x 1'.3--Mag. 13.05: Also takes high power well. Stellar core. 3 faint stars beside it. First seen at 60x.
6692: 1' x 0'.7--Mag. 13.05: Spotted at 100x near a colourful, wide double. Very near a 9 mag star, so averted vision gives best views. 200x appropriate.
6671: 1'.5 x 1'.3--Mag. 13.1: Easily spotted at 60x, within a bright, rich star field, and directly amidst a short, curving string of stars. Stellar core and fainter halo obvious. Fine up to 250x. Faint star N.
I-1288: 1'.1 x 0'.7--Mag. 13.2: In the same 100x field with 6646, above. Smaller and fainter than that galaxy, but not difficult on a good night. Between two faint stars.
6606: 0'.9 x 0'.7--Mag. 13.25: Located at 60x. Good views up to 150x. Again, it is in a bright field of stars.
There you have the top ten galaxies, by brightness. Told you there was nothing special. Still, I enjoy the hunt, and also surprising others when you say that you are observing galaxies in Lyra (lots of them)! Here are the rest, in order of brightness. For some of these I wish I'd used the astronomy club's 14". For the two I did not locate, perhaps I will use it. The following galaxies were all seen best using averted vision.
6695: 1'.1 x 0'.7--Mag. 13.3: Located SF a string of 3 bright stars running N-S. Faint, oval.
6640: 1'.1 x 0'.8--Mag. 13.35: Observed at 120x and 150x. Not small, but faint.
6657: 1' x 0'.6--Mag. 13.35: A wide slash at 120x and 150x. Near 6640.
6713: 0'.4 x 0'.3--Vis. Mag. 13.4: Because of its tiny size, the surface brightness of this is listed as 11 mag. Don't be fooled. Small, though not as small as one might expect. Best at 150x. Elusive.
6685: 1'.1 x 0'.9--Mag. 13.45: Seen at 125x and 150x. Very faint star pair nearby. Round.
6700: 1'.4 x 1'--Mag. 13.5: Oval, not difficult. Seen well from 100x to 200x. Very faint star involved or adjacent.
6710: 1'.7 x 1'--Mag. 13.55: Bright field stars makes this one a challenge. Quite small and faint.
6745: 1'.3 x 0'.5--Mag. 13.7: Spotted easily at 100x just NP V547 and close to a mag. 9 star. Seen well at 125x, 150x, and 200x, and possibly the most interesting galaxy of the bunch. Very elliptical, lying between two faint star groups. 3 galaxies are colliding, and there is a remarkable Hubble Heritage photo of this object! Easy to find using Uranometria.
6662: 1'.5 x 0'.5--Mag. 13.75: Located at 125x, the elongation was not noticed. Central area appeared stellar at times.
6663: 1' x 0'.9--Mag. 13.75: Close to Vega. Near a lovely triple star. Brightness of star hampers location of this very faint galaxy. Viewed over multiple evenings for confirmation.
6665: 1'.1 0'.6--Mag. 13.75: This took several tries, but once seen was not difficult to view. Oval at 125x and 150x. Just S of a curving star group.
6740: 0'.9 x 0'.8--Mag. 13.95: Visual mag. is 14.2. Threshold object at 125x. Round and better at 150x. Just S of oc 6743.
6612: 0'.7 x 0'.7--Mag. 14.05: Visual mag. is 14.5. Took several nights to locate. Found on the best of nights without difficulty at 125x. Also viewed at 150x and 200x. What else can one say about excellent sky conditions?
I 1289: 0'.7 x 0'.3--Mag. 14.1: Visual mag. is 15! Took several nights of trying. Seen at 125x, 150x and 200x. Oval and very faint. Nearby 6646 and I 1288 much easier.
6672: 0'.2 x 0'.1:--Mag. 14.1: Visual mag. is 15! Seen at 150x and 200x. A tiny, faint threshold object makes a close triangle with 2 stars, mag. 9 and 12. Huzzah!
Two objects remain unseen.
.
I 1286: Mag. 14.15: Immediately NP M 57. Located within a faint circlet of stars.
6686: Mag. 14.45: Too close to a bright star (7.5 mag.).
I really did enjoy my five-night tour through Lyra! Next up, a deep investigation of Cygnus.
Mapman Mike
6695: 1'.1 x 0'.7--Mag. 13.3: Located SF a string of 3 bright stars running N-S. Faint, oval.
6640: 1'.1 x 0'.8--Mag. 13.35: Observed at 120x and 150x. Not small, but faint.
6657: 1' x 0'.6--Mag. 13.35: A wide slash at 120x and 150x. Near 6640.
6713: 0'.4 x 0'.3--Vis. Mag. 13.4: Because of its tiny size, the surface brightness of this is listed as 11 mag. Don't be fooled. Small, though not as small as one might expect. Best at 150x. Elusive.
6685: 1'.1 x 0'.9--Mag. 13.45: Seen at 125x and 150x. Very faint star pair nearby. Round.
6700: 1'.4 x 1'--Mag. 13.5: Oval, not difficult. Seen well from 100x to 200x. Very faint star involved or adjacent.
6710: 1'.7 x 1'--Mag. 13.55: Bright field stars makes this one a challenge. Quite small and faint.
6745: 1'.3 x 0'.5--Mag. 13.7: Spotted easily at 100x just NP V547 and close to a mag. 9 star. Seen well at 125x, 150x, and 200x, and possibly the most interesting galaxy of the bunch. Very elliptical, lying between two faint star groups. 3 galaxies are colliding, and there is a remarkable Hubble Heritage photo of this object! Easy to find using Uranometria.
6662: 1'.5 x 0'.5--Mag. 13.75: Located at 125x, the elongation was not noticed. Central area appeared stellar at times.
6663: 1' x 0'.9--Mag. 13.75: Close to Vega. Near a lovely triple star. Brightness of star hampers location of this very faint galaxy. Viewed over multiple evenings for confirmation.
6665: 1'.1 0'.6--Mag. 13.75: This took several tries, but once seen was not difficult to view. Oval at 125x and 150x. Just S of a curving star group.
6740: 0'.9 x 0'.8--Mag. 13.95: Visual mag. is 14.2. Threshold object at 125x. Round and better at 150x. Just S of oc 6743.
6612: 0'.7 x 0'.7--Mag. 14.05: Visual mag. is 14.5. Took several nights to locate. Found on the best of nights without difficulty at 125x. Also viewed at 150x and 200x. What else can one say about excellent sky conditions?
I 1289: 0'.7 x 0'.3--Mag. 14.1: Visual mag. is 15! Took several nights of trying. Seen at 125x, 150x and 200x. Oval and very faint. Nearby 6646 and I 1288 much easier.
6672: 0'.2 x 0'.1:--Mag. 14.1: Visual mag. is 15! Seen at 150x and 200x. A tiny, faint threshold object makes a close triangle with 2 stars, mag. 9 and 12. Huzzah!
Two objects remain unseen.
.
I 1286: Mag. 14.15: Immediately NP M 57. Located within a faint circlet of stars.
6686: Mag. 14.45: Too close to a bright star (7.5 mag.).
I really did enjoy my five-night tour through Lyra! Next up, a deep investigation of Cygnus.
Mapman Mike
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