Thursday, July 23, 2009

Two Nights With New Sights

Richard Navarrete and I observed Tuesday and Wednesday nights from Deep Sky Ranch, south of Hollister in San Benito County. Conditions both nights were excellent. Richard was using an equatorial platform he'd just purchased along with his 18" Obsession, I had my 18" Obsession undriven. I was impressed with the performance of the platform, and am convinced it allows a more relaxed observing session. I had great success both nights, logging many new targets that were both interesting and challenging. I did not do a star count or use an SQM, but both seeing and transparency were excellent. We observed until dawn the first night, and to about 2:30 the second night. My target list was compiled from objects between RA 19:40 and 20:39:59. First night I started in the north and worked south, next night from the south to the north. Aside from what I observed in my telescope, I spent a good amount of time looking at Hickson groups in Richard's scope - I believe we were seeing into the mid 17th magnitude. If I had to pick out a few objects I viewed and say they were highlights, they'd be the views of the Crescent Nebula, Sh2-101 and Sh2-100 which I refer to as a planetary, but it isn't. I also had the opportunity to use some new eyepieces with 82 degree fields, that performed very nicely.

Here are the targets I viewed, and my observing notes:

ARP 29 11.6'x9.9' 8.8 20 34 52 60 09 NGC 6946

Large core with two arms coming off to NE and swinging E. Southern of the 2 arms is fatter. Dimmer arm comes off S of core and swings tightly around to W. Large core has a gradually brighter center. Finally noticed another long arm, from WNW and winding around straight to NE.

Abell 71 Cyg 165"x150" 14.5 20 32 23.2 47 21 04 PK 85+4.1 = PN G084.9+04.4 = Sh 2-116

7mm 18" - very dim glow, no definition at all, surrounding a mag 13.5 star with more "glow" around a mag 12.5 star on the edge. Extremely difficult. Dim star actually appears involved in a haze.



Sh 2-115 50 2 20 34 33.0 46 52 40

12mm UHC 18" - dim linear glow with some structure running E/W of two pair of stars to the S. Dimmer pair appears involved in nebulosity. OC Berk 90 is obvious at E of the two pair of stars.





Sh 2-112 15 2 20 33 50.2 45 39 35

12mm UHC 18" - easy to view this Sharpless around GSC49801. Nebulosity forms an arc through the star, running mostly N/S and arcing to the E, forming a J with most but thinnest section to the N. Bottom of J is most pronounced.



AGC 2319 0.973 15.4 19 20.8 43 59

7mm 18"- Viewed CGCG230-9, CGCG230-8, CGCG230-7 and CGCG230-4




Sh 2-108 180 3 20 22 34.8 40 15 15 IC 1318

30mm 18" - nebulosity with dark veins throughout over large areas around Gamma Cygni, through into the North American Nebula. Outstanding views throughout the entire area. Truly great view of the North American, rivaled only by high elevation views at Mount Lassen.

Abell 69 Cyg 25"x22" 20.2 20 19 58.3 38 24 02 PK 76+1.1 = PN G076.3+01.1

7mm 18" - perhaps at most the southern arc of this planetary is visible, very elusive.















Sh 2-105 18 3 20 12 02.4 38 20 59 N6888 = Crescent Nebula

12mm 18" UHC - spectacular view, wispy nebula with blue glow and blue stars. Internal knots inside western edge, northern and eastern edge very thick and distinct. Mottling throughout. Star embedded in northeastern wisp is very reminiscent of Veil Nebula's Witches Broom.



Sh 2-106 3 3 20 27 26.9 37 23 49

12mm 18' UHC - amorphous glow involved with dark veins interspersed in distinct star field just NNW of SAO 70038. Subtle, but there.


Sh 2-104 7 2 20 17 44.6 36 44 40

12mm 18" UHC - faint but distinct even nebulosity surrounding stars of Dolidze 4, elongated E/W, with a "Pac-Man" type notch taken out of the NW edge.



Sh 2-101 20 2 19 59 56.8 35 17 27

12mm 18" NPB - reminiscent of Crescent, but dimmer. Two bright stars embedded in W end of nebula. Brightest portion is to N and E of bright stars, Another bright section runs E of the S star of the pair. More nebulosity is to th S and W of the pair of stars, but much more subtle. This is a very good target.


Sh 2-100 4 3 20 01 50.6 33 30 41 N6857

7mm 18" NPB - planetary appears almost triangular, nearly as distinct without the filter. Elongated slightly NW/SE. But appears to have somewhat triangular shape, with a harder edge running N/S. Star embedded in nebula, but seems offset to the N, which may be an illusion due to a dim northern edge of the shell.



Sh 2-77 8 1 19 48 16.6 01 08 52

12mm 18" - very faint and tenuous nebulosity, very indistinct, around a few stars and perhaps between. Nothing certain.





Abell 70 Aql 45"x40" 14.7 20 31 33.2 -07 05 17 PK 38-25.1 = PN G38.1-25.4

12mm 18" - entire disk shows without filter but NE section is clearly brighter. 7mm shows annularity and galaxy visible through NE edge of nebula.


Palomar 11 10.0' 17.3 19 45 14 -08 00 26

12mm 18" - obvious granular appearance and bracketed by 2 concave chains of 4 = mag stars each running N/S with a bright star nearby to the N.








NGC 6822 15.5'x13.5' 8.8 19 45 00 -14 48 NGC 6822 19 45.0 -14 48 15.5x13.5 8.8

12mm 18" - elongated NE/SW and embedded in stars, there is a dark rift or two that run along the major axis and several HII regions embedded, most noticeably the two at the NE end of the object.
Using an NPB filter shows the entire NE portion of the galaxy as a triangle glowing in HII.


SagDIG 3.2'x1.5' 15.0 19 30 00 -17 41 00 SagDIG 19 30.0 -17 41 3.2x1.5 15

7mm 18" - oval glow between parallelogram of stars, elongated NW/SE and appearing almost annular - no doubt it is there.







Abell 66 Sgr 295"x241" 19 57 31.5 -21 36 46 PK 19-23.1 = PN G019.8-23.7

12mm 18" - Pair of stars equal mag nearby to NNE. Planetary is large and perhaps elongated slightly N/S with slight annularity. Dim stars appear embedded in E edge - perhaps 2. Very faint, although occasionally the central area appears to brighten and negate annular feeling.



Sh 2-052 2 2 19 47 46.3 -23 05 15
See next entry - how many types of catalogs is this in!

Abell 65 Sgr 134"x34" 13.8 19 46 33.8 -23 08 12 PK 17-21.1 = UGCA 415 = MCG -04-46-001 = PN G017.3-21.9 = PGC 63654

12mm 18" - visible without filter, but UHC helps. Round and mostly even brightness, but SW edge seems brighter than rest of disk. Chain of 4 dim stars cup N edge, and 3 dim stars extend W from S edge, with E star touching disk.

Hickson 086D 0.3x0.2 14.7 19 51 51.9 -30 48 30 63749
7mm 18" not observed, or if so a very tight split with Hickson 86B


Hickson
086B 0.5x0.4 13.8 19 51 59.0 -30 48 57 63748
7mm 18" observed

ESO 461-007 1.2'.7' 13.3 19 52 06 -30 49 00
7mm 18" observed, aka Hickson 86A

Hickson 086A 1.2x0.7 13.3 19 52 08.7 -30 49 30 63753
7mm 18" observed.

Hickson 086C 0.4x0.3 14.9 19 51 57.3 -30 51 23 63752
7mm 18" observed.


Terzan 8 3.5' 12.4 19 41 45 -34 00 01

12mm 18" - forms an almost equilateral triangle with GSC 7434:401 and GSC 7434:31, but feeling is I'm seeing the core as it is relatively small and not all that difficult.