Fiddletown Fun 1/12/02

by Steve Gottlieb

Thanks to the entire Sacramento contingent that showed up at Fiddletown on Saturday night -- it was a great to get in a full evening of observing with nice company. I tracked down and took notes on nearly 50 objects but here were a few of the highlights:

I've been working sporadically on identifying and observing globulars in M31 since 1993 and I'm now up to 28 clusters including two from Saturday night. G52 is in a great location -- just off the west side of the starcloud NGC 206 at the SW end of M31. Just a stellar 16th mag point, but still neat to see any globular at over 2.5 million light years. G219 actually showed a small nonstellar fuzzy glow (verified by Randy) and what's more interesting is that it has been twice classified as a galaxy! Once by Fritz Zwicky in the late '60's and also by Markarian.

M31-G52	00 40 20.3 +40 43 59	V = 15.7
17.5": this 16th magnitude M31 globular was extremely faint, stellar, just visible continuously with averted and concentration at 380x. Two mag 13 stars lie 2.0' S and 3.7' SW. Situated just 2' W of the starcloud N206 at the SW end of M31!
M31-G219 = Mayall IV = IV Zw 30 = Mrk 959	00 43 17.8 +39 49 13	V = 15.1
17.5": picked up at 220x as a very faint mag 15 "star", possibly quasi-stellar. At 380x, appears as barely nonstellar glow, ~2" in diameter. Easily visible at this power.

I also revisited a couple of PNe that I had last observed over 15 years ago with my old Coulter 13". These were very challenging in the 13" and somewhat easier on Saturday night with my 17.5". Observations with both apertures are included below --

Baade 1 = PK 171-25.1 = PN G171.3-25.8	03 53 36.6 +19 29 41	V = 15.8; Size 40"
17.5" (1/12/02): at 100x using an OIII filter, Ba 1 appeared very faint, fairly small, round, 0.6' diameter, crisp-edged. Situtated just following a 15' NW-SE string of 7 stars mag 11-13 and 2.3' S of a mag 10.7 star (poor position in ESO-Strasbourg catalogue). Can just hold steadily with concentration - not surprising as the visual mag is just 16. 13": at 166x and Daystar 300 filter appears extremely faint and near my visual threshold. Cannot hold steadily with averted vision, fairly small, round, very low even surface brightness. A bright right triangle of mag 10 and 11 stars is roughly 6' NE, with the NE vertex consisting of a wide 30" pair.
Abell 20 = PK 214+7.1 = PN G214.9+07.8	07 22 57.4 +01 45 37	V = 14.7; Size 65"
17.5" (1/12/02): at 100x with an OIII filter this moderately large planetary appeared very faint, round, evenly lit, crisp-edged. With concentration I could almost hold it continuously. The magnitude must be fainter than Jack Marling's computed V = 14.0 (Owen Brazell gives V = 14.7). A mag 10 star lies 3.2' WSW. 13" (12/7/85): extremely faint at 79x and OIII filter, fairly small, round. Difficult to view and cannot hold steadily with averted, estimate V = 14.5-15. Located 3.3' ENE of a mag 10.5 star.

My favorite galaxy of the evening was NGC 1569 -- a starburst galaxy in Camelopardalus. There has been a lot of professional interest lately in this galaxy, as deep images reveal a pair of giant star clusters in the core. I was able to resolve these at 400x (looked like a double nucleus or a couple of faint superimposed "stars" before the seeing turned a bit softer later in night. The galaxy itself is remarkably asymmetric although I haven't much mention of it in the past. My first observation of it goes back 20 years with a C8!

N1569 = U03056 = MCG +11-06-001 = CGCG 306-001 = Arp 210 = VII Zw 16 = LGG 104-002	04 30 48.6 +64 50 56	V = 11.0; Size 3.6x1.8; SB = 12.9; PA = 120d
17.5" (1/12/02): very bright, elongated 5:2 WNW-ESE, 2.5'x1.1', high but irregular surface brightness with an asymmetric appearance. The very bright core is mottled and irregular and is offset to the NW side of the galaxy! At 380x, there are two stellar "nuclei" within this glow. The brighter stellar nucleus is fairly easy and a fainter stellar point is close SE. There is also a strong impression of a third stellar spot close W of the central nucleus. These faint "stars" are actually luminous super-star clusters, the most massive known type of star clusters (color image at http://www.lowell.edu/users/dah/n1569p1_color.gif ). A mag 10 star is close off the N side, 1' from center and a mag 13 star is just off the SE end. N1569 is probably a member of the Maffei 1 - IC 342 group. 13" (1/18/85): very bright, elongated 2:1 WNW-ESE, high surface brightness, elongated bright core, mottling suspected. Located just 1' S of a mag 10 star. 8" (11/28/81): fairly bright, small, elongated. Located just south of a mag 9 star.

N1569 = U03056 = MCG +11-06-001 = CGCG 306-001 = Arp 210 = VII Zw 16 = LGG 104-002

04 30 48.6 +64 50 56

V = 11.0; Size 3.6x1.8; SB = 12.9; PA = 120d

17.5" (1/12/02): very bright, elongated 5:2 WNW-ESE, 2.5'x1.1', high but irregular surface brightness with an asymmetric appearance. The very bright core is mottled and irregular and is offset to the NW side of the galaxy! At 380x, there are two stellar "nuclei" within this glow. The brighter stellar nucleus is fairly easy and a fainter stellar point is close SE. There is also a strong impression of a third stellar spot close W of the central nucleus. These faint "stars" are actually luminous super-star clusters, the most massive known type of star clusters (color image at http://www.lowell.edu/users/dah/n1569p1_color.gif ). A mag 10 star is close off the N side, 1' from center and a mag 13 star is just off the SE end. N1569 is probably a member of the Maffei 1 - IC 342 group.

13" (1/18/85): very bright, elongated 2:1 WNW-ESE, high surface brightness, elongated bright core, mottling suspected. Located just 1' S of a mag 10 star.

8" (11/28/81): fairly bright, small, elongated. Located just south of a mag 9 star.

For a really distant galaxy, I took a look at Hydra A -- discovered as one of the first radio sources and shining over a distance of 800 million l.y. (much further than the well known Abell clusters in Perseus, Leo, Coma, Hercules, etc.). When I saw the DSS image, I realized that it was also the brightest member of a distant cluster -- catalogued as Abell 780.

Hydra A = MCG -02-24-007 = 3C 218	09 18 05.7 -12 05 44	V = 12.9; Size 0.7x0.7; SB = 12.1
17.5": very faint, very small, round, 20" diameter. Appears as a small, round knot. Forms the eastern vertex of a small isosceles triangle with a 10.8 star 1.0' W and a mag 12 star 1.0' SW. This radio galaxy is the brightest member of Abell 780. Located 26' WSW of mag 4.8 26 Hydrae.