I went to the D.A.R.C. observatory last Saturday to observe or re-observe a few Herschel 400 summer objects, as well as enjoy some eye candy under a dark sky. I was setup right next to Dennis Beckley and his classic Obsession 18″. Here is a summary of the weather conditions:
- Wind died down shortly after sunset
- Temperature in the low 70s
- Good seeing (6 to 7 on the Pickering scale)
- Average transparency (the light dome from Los Banos, which I use as an indication of the moisture content in the atmosphere, was fairly conspicuous)
- NELM 6.7 in Lyra
- Thin clouds started showing up around 1am from the east
Overall, it was a pretty good night, although not as good as what the D.A.R.C. observatory has proven capable of. Among the highlights of the night, I got to observe Triton for the first time. The Jupiter impact mark was seen very easily, and Jupiter’s satellites were resolved as tiny discs of different diameters. The “ink spot” (Barnard 86 located right next to OC NGC 6520) looked absolutely remarkable. Stephan’s quintet was looking pretty good in my scope, and was easy in Dennis’ 18″ scope. Finally, I really enjoyed looking at V Aql, a fairly bright carbon star of deep orange color with a tinge of red. What is interesting about this star, beyond its striking color, is the presence of planetary nebula NGC 6751 about 30′ SE. It is therefore possible to fit both objects within the same field of view in modest amateur telescopes (8 to 12″), portraying two stages of stellar evolution as the carbon star will eventually become a planetary nebula in a not so distant future.
On Sunday morning, I had an immense satisfaction when I looked at a DSS image of galaxy NGC 6217 (Arp 185), and noticed that my notes (see below) were absolutely right on! I find it absolutely amazing that such wispy details can be detected with such a small aperture under a good dark sky.
I cannot end this report without thanking Dr. Lee Hoglan for letting us observe on his property. Below is my log for the night. Cheers!
Location: D.A.R.C. Observatory [Elevation 1400ft]
Telescope: Meade Lightbridge 12″ F/5
- Televue Panoptic 27mm (56x - 1.2° TFOV)
- Televue Nagler 16mm type 5 (95x - 52′ TFOV)
- Televue Nagler 9mm type 6 (169x - 29′ TFOV)
- Televue Nagler 7mm type 6 (217x - 22′ TFOV)
- Televue Nagler 5mm type 6 (305x - 16′ TFOV)
(All times in PDT)
NGC 6217 GX UMi 16h32m15.6s +78°10’52″ 11.9 mag 10:15p
Small, faint, elongated 3:2 NW-SE, fairly faint stellar core or super imposed star. Very faint super imposed star about 20″ SE, another one about 2.5′ NW. Hints of two spiral arms, one on the N side going E, and another one on the S side going W. This observation was later beautifully confirmed with a DSS image.
NGC 6834 OC Cyg 19h52m37.2s +29°26’04″ 9.7 mag 10:30p
Seen as a tiny smudge in a 9×50 finder scope. Small grouping of about 30 moderately bright stars. One brighter star in the middle, with a possible slight yellow tinge. Located in a region with relatively few stars (dark nebula?) in an otherwise crowded milky way star field. For some reason, I found it hard to star-hop to…
NGC 6866 OC Cyg 20h04m16.1s +44°11’11″ 9.1 mag 10:40p
About 30 fairly bright stars within a region 15′ in diameter. Detected in 9×50 finder scope.
NGC 6910 OC Cyg 20h23m34.7s +40°48’37″ 7.3 mag 10:45p
Small group of about 15 stars, elongated 2×1 WNW-ESE (dimensions: 10′ x 5′) The two brightest stars have a yellow tinge. Located about 30′ N of Gamma Cyg (Sadr)
NGC 7044 OC Cyg 21h13m32.8s +42°32’06″ 12.0 mag 10:50p
Small compact group of maybe 50 faint stars (hard to get a reliable star count) scattered within a circular region of about 5′ in diameter.
NGC 6522 GC Sgr 18h04m14.3s -30°02’08″ 9.9 mag 11:00p
Fairly small, moderately faint, fairly well defined core, halo appears grainy. There is a moderately bright star located about 30″ E which probably does not belong to this cluster. Forms a beautiful couple with globular cluster NGC 6528 located about 15′ E.
NGC 6528 GC Sgr 18h05m28.3s -30°03’25″ 9.6 mag 11:00p
Fairly small, moderately faint, fairly well defined core, unresolved. Located at the NW edge of B298. Forms a beautiful couple with globular cluster NGC 6522 located about 15′ W. This cluster is slightly dimmer than its neighbor NGC 6522 (some of its light may be absorbed by B298?)
NGC 6818 PN Sgr 19h44m32.6s -14°07’45″ 10.0 mag 11:25p
Tiny fairly bright disk, almost circular (extremely slightly elongated NS) showing a delicate bluish tinge, especially at low power. At higher magnification, the center of the nebula appears very slightly darker. The central star (mag 15.0) was not seen. Located inside a small triangle of moderately bright stars.
NGC 6664 OC Sct 18h37m10.4s -07°48’17″ 8.5 mag 11:45p
About 60 moderately faint stars within 15′. This cluster appears slightly elongated N-S, and is located about 25′ NE of Alpha Sct, which has a fairly distinctive yellow tinge.
NGC 6712 GC Sct 18h53m37.6s -08°41’33″ 8.1 mag 11:50p
Moderately large and bright with a poorly defined core region. Many stars are resolved over a milky background.
NGC 6802 OC Vul 19h31m02.2s +20°16’59″ 11.7 mag 12:50a
Small (5′ x 2′) compact group of about 25 very faint stars, elongated N-S. Located just east of the famous coat hanger asterism (Cr 399)
NGC 6823 OC Vul 19h43m35.6s +23°19’27″ 7.1 mag 12:55a
About 30 fairly bright stars scattered within 6′ around a small group of 4 bright stars and a few fainter ones. Not very conspicuous in a crowded star field. Nearby nebula NGC 6820 was not seen (although I did not really look for it and thus was not using a nebula filter)
NGC 6830 OC Vul 19h51m25.8s +23°07’33″ 8.9 mag 01:00a
Very inconspicuous grouping of about 20 fairly bright stars.
NGC 6934 GC Del 20h34m41.3s +07°26’22″ 8.9 mag 02:00a
Relatively small, fairly bright, intense core. A great number of stars are resolved throughout at 217x.