Lake Sonoma 8/17/04

by Steve Gottlieb


After a pretty chilly and windy Saturday night at Lake Sonoma I returned last night (Tuesday, 8/17) to surprisingly warm conditions in the '70's. During the summer months, the evening commute traffic heading north on 101 is a lot lighter than usual and I breezed through San Rafael, Petaluma and Santa Rosa from 6:30 to 7:30 without a slowdown. On Saturday night there was at least 15 observers, but on Tuesday I had the huge Lone Rock lot to myself.

I started off working through some double stars in Cepheus and after twilight ended decided to continue in Cepheus, mostly with open clusters. Seeing was fair, generally 2" or so, though early in the evening I split a couple of 1" doubles with some careful viewing.

Here's the rundown on the deep sky objects in Cepheus, along with older observations ...

NGC 6939 = Cr 423 = Mel 231 = Lund 960 20 31 30 +60 39.7 V = 7.8; Size 8
18" (8/17/04): this triangular-shaped rich cluster is beautifully framed in the 160x field (24'). The cluster is enclosed within a kite asterism of four mag 10 stars with two of these stars near the east and west vertices of the triangular outline. ~125 stars are visible in a 10' diameter, with most of the stars mag 12-14. Just west of center is a very rich 3' group and just following this group is a small knot of 4 very faint stars. The west side is well-defined by a string of mag 12 stars oriented NW-SE.

17.5" (9/14/85): about 100-140 stars mag 12-15 are resolved. Difficult to count as stars fill the 22' field at 220x with no distinct boundaries. N6946 is located less than 40' SE.

13" (7/27/84): ~80 stars resolved but richness makes an accurate count difficult.

13" (7/5/83): ~70 stars resolved at 166x, very rich, beautiful in faint stars.

NGC 6951 = UGC 11604 = MCG +11-25-002 = CGCG 325-003 = N6952 20 37 14.2 +66 06 20 V = 10.7; Size 3.9x3.2; SB = 13.3; PA = 170d
18" (8/17/04): at 225x appears moderately bright and large, oval 3:2 WNW-ESE, ~1.8'x1.1'. On the east end is a mag 12.5 star. The galaxy suddenly brightens to a very small, brighter core. The edge of the halo fades and increases in size with averted vision. Appears slightly brighter along the major axis with a hint of structure.

17.5" (10/30/99): observed SN 1999el which was discovered 11 days ago (Oct. 20th). Appeared as a mag 14.5-15 star just following the core (22" E and 8" S) and easily visible at 280x. The galaxy is fairly faint, moderately large. Sharply concentrated with a small bright core surrounded by a diffuse halo elongated 3:2 E-W. A mag 12 star is 1.5' following the center and a mag 15 star is just visible a similar distance WNW.

17.5" (8/13/88): bright with a very bright core surrounded by a fainter large oval halo 3:2 E-W. A mag 13 star is just off the E edge 1.4' from center and a mag 15 star is off the NW end.

8" (6/22/81): faint, small, bright core. A mag 13 star is at the E edge.

NGC 7139 = PK 104+7.1 = PN G104.1+07.9 21 46 08.6 +63 47 29 V = 13.4; Size 86"x70"
18" (8/17/04): easily picked up at 115x unfiltered. At 225x appears moderately bright and large, slightly elongated ~N-S, ~1.2'x1.0'. A mag 13.5 star is just off the SE end. The rim appears to be slightly brighter, particularly along the SE side towards the mag 13.5 star.

17.5" (10/13/01): easily picked up sweeping at 100x without a filter. Appears moderately bright, round, 1.2' diameter, crisp-edged. A mag 13.5 star is off the SE edge. Excellent view at 280x without filter. The surface brightness appears irregular with a slightly brighter rim, particularly along the eastern half of the rim. An extremely faint star is intermittently visible right at the NE edge. A nice, elongated group of 6-8 stars follows the planetary in the same high power field. Central star not seen at 280x.

17.5" (8/8/91): moderately bright, fairly large, slightly elongated, 1.2' diameter. A mag 13.5 star is just off the SE edge 40" from the center. A slightly darker center is visible with an OIII filter at 140x but the annularity is subtle. No central star visible.

8" (8/28/81): extremely faint, moderately large, round, difficult, a faint star is near the south edge. Located about 4' NW of a faint curving arc of stars and 23' E of mag 7 SAO 19595. This is one of the faintest planetaries observed with the C8.

NGC 7160 = Cr 443 = Lund 1002 = OCL-236 21 53 40 +62 36.2 V = 6.1; Size 7
18" (8/17/04): at 160x, ~40 stars are visible in a 8'x6' group, extended SW-NE. The cluster is dominated by two mag 7 and 8 stars that are separated by 1'. Both of these stars have much fainter companions. Another nice, mag 13 pair is SW of the mag 7 star. Stands out well in the field.

17.5" (10/5/91): about three dozen stars in a 7' diameter. Very bright, elongated SW-NE although scattered outliers make the cluster rounder. Includes several fairly bright stars with two stars mag 7.0/7.9 at 1.0' separation NE of center which are surrounded by a semicircle of nine stars. Includes several double stars with a mag 10 star which has a very faint companion on its W side. Not rich but distinctive. Mag 6.8 SAO 19698 is 11' NW at the edge of the field.

8" (10/31/81): about two dozen stars in a bright cluster, not dense, includes two mag 8 stars.

NGC 7226 = Cr 446 = Lund 1007 = OCL-226 22 10 26.9 +55 23 54 V = 9.6; Size 2
18" (8/17/04): at 225x, this is a small, faint group with 25-30 stars resolved in a 2'-2.5' region. The star at the NE edge is a nice, mag 12/13 double. The remaining stars are generally 14th-15th magnitude and some pop in and out of view.

17.5" (11/2/91): 15 stars resolved at 220x within a compact 2' diameter. The brightest mag 11 star is at the WNW edge and a close double star mag 12/13 at 11" is at the NE edge. The remaining dozen very faint stars are 14th and 15th mag and located along the south side. Situated in a rich star field over unresolved background haze.

NGC 7235 = Cr 447 = Lund 1008 = OCL-229 22 12 25.0 +57 16 16 V = 7.7; Size 4
18" (8/17/04): at 225x, nearly three dozen stars are resolved in a 4'x3' group, slightly extended E-W. The brightest mag 9 star is at the east end. A rich stream of faint stars over haze is the north side and angling WSW towards a mag 10.5 star on the west end.

17.5" (11/2/91): two dozen stars mag 9-15 in a 4' diameter at 220x. This moderately concentrated group is elongated WNW-ESE and includes several fairly bright stars. A mag 9 star is at the east end and there are eight other mag 10-11 stars. Just west of the mag 9 star is a 1.5' circular hole with no stars. A mag 10 star at the extreme west edge has six faint stars mag 13/14 close following.

NGC 7261 = Cr 450 = Lund 1013 = OCL-237 22 20.2 +58 05 V = 8.4; Size 6
18" (8/17/04): at 225x, ~30 stars are resolved in an 7'x3.5' group, elongated N-S. A couple of scattered groups of stars are to the south, but are apparently detached. 7 stars on the south side form the outline of a perfect rectangle with the eastern vertex the brightest star in the cluster (mag 9.5 SAO 34332). There are no stars within the interior of this rectangle. The richest group of stars is just north of the rectangle.

17.5" (10/5/91): about 30 stars in a 7'x3' region elongated N-S. Set over a background of some unresolved haze on the N side of cluster. Includes six brighter stars with a mag 9 star on the SE side. Fairly rich in faint stars on the N side although not rich in other sections.

NGC 7354 = PK 107+2.1 = PN G107.8+02.3 22 40 19.9 +61 17 07 V = 12.2; Size 28"x20"
18" (8/17/04): at 225x, moderately bright, fairly small, ~30" diameter. A mag 14 star is just of the SW edge with a mag 14.5 star a bit further west. At 435x appears slightly brighter along portions of the rim, particularly along the SE side.

17.5" (11/6/99): a fairly bright, 25" disc is visible at 100x with one or two stars very close. At 280x, the PN is slightly elongated E-W, ~25"x20". A mag 14 star is close off the SW edge, 30" from center and a mag 14.5 star is 0.6' due W. At 380x, a mag 15-15.5 star is 0.6' WNW and the surface brightness is noticeably irregular with hints of brighter areas.

13" (7/12/86): fairly bright, fairly small, slightly elongated. A mag 14 star is just off the SW edge. Pretty with a UHC filter at 166x, estimate V = 12.0. Takes high power without a filter.

8": faint, small, round, but easily visible at 100x or higher and takes 200x. Very faint star is at the SW edge.

NGC 7419 = Cr 453 = Lund 1024 = OCL-250 22 54 20.1 +60 48 55 Size 2
18" (8/17/04): at 160x this is a small group of 25-30 stars down to mag 15, elongated 3'x1' NW-SE. Located ~3' SE of a mag 8 star. The brightest mag 9.5 star is at the NE tip of the cluster and the fairly rich cluster follows to the SE. A faint pair is near the center of the group

13.1" (8/25/84): about a dozen faint stars are visible over unresolved haze with a mag 9.5 star at the NW edge. Appears to be a rich group. Mag 8.2 SAO 20306 is just off the NW edge. About 12' NW is the double star …2953 = 7.8/9.8 at 8".

IC 1470 = Sh 2-156 = Hb 10 23 05 10.3 +60 14 37 Size 1.2x0.75
18" (8/17/04): at 220x, this is a fairly bright, moderately large, 1' tear-shaped glow extending from a 12th magnitude star. Nebulosity extends most S and SE of the star. A close, faint double star lies 1.9' W. Several extremely faint stars are near including one just off the SE edge and one close NE.

17.5" (10/30/99): picked up at 100x using an OIII filter as a small, bright glow surrounding a mag 12 star. Best view at 280x unfiltered. The involved star is attached at the N edge and the 1' oval nebula appears to hang off the S side of the star. Close west is a very close, evenly matched faint double star!

13" (9/22/84): appears as a mag 12 star with a faint but easily visible oval nebula surrounding the star. Extends mainly SE with the 12th magnitude star at the tip. Visible without a filter. Similar to Hubble's Variable Nebula.

King 19 = OCL-254 = Lund 1028 23 08 22 +60 31.0 V = 9.2; Size 6
18" (8/17/04): at 160x, ~20 stars are visible in a 4' group. Includes 5 brighter mag 10-11.5 stars. The remaining stars are sprinkled fairly evenly in a circular group. Located 20' W of N7510. Emission nebula IC 1470 lies 29' SW.


Posted on sf-bay-tac Aug 18, 2004 22:31:39 PT
Converted by report.pm 1.2 Jan 08, 2005 20:47:14 PT