NGC 6811 (Lund 897, Cr 402) Open Cluster in Cygnus
Located at: RA 19 hours 37 minutes 13 seconds, Dec +46 degrees 21 minutes 50 seconds
Size: 12' (15'); Magnitude: 6.8; Class: III 1 r
North is up

West to the right
| Telescope: |
8" f5 Newtonian reflector |
| Camera: |
ST-8XME, self-guided, binned 1x1, temp -15c, camera control MaxIm DL 4.54 |
| Image: |
Red (Hoya 25A) filter, 110 minutes (11 x 10 minute subs), 08/5/2006 |
| Processing: |
CCDStack 1.1, Photoshop 7.0 |
| Location: |
Rolling Roof Observatory, Thousand Oaks, California 91360 (+34d 13m 29s -118h 52m 20s) |
| Notes: |
According to "Star Clusters", by Brent Archinal
and Steven Hynes, the size of this open cluster is 15 arc
minutes. From the NGC / IC Project: Contemporary Visual Observation(s) for NGC 6811 NGC 6811 = Cr 402 = Mel 222 = Lund 897 19 37 17 +46 23.3 V = 6.8; Size 13 17.5" (7/1/00): this a large, beautiful cluster at 100x. The central section is ~8' in diameter, roughly triangular and contains a scattering of ~20 10-11th magnitude stars. There are no prominent members - the brightest star (at the west edge) has a faint companion. Perhaps 85 stars are resolved in the unconcentrated central region (there is nearly a void in the center) over haze. The richest knot of stars is on the NE side. An isolated 5' tails of stars extends NW and another curving string of stars can be traced 8' to the east. 13": fairly large and rich group of approximately 60 stars including many mag 11-12 stars. A long trail of stars follows and a bright group of stars is WNW. - by Steve GottliebHistorical Research Notes / Correction for NGC 6811 NGC 6811. JH has two observations of this, separated by nearly a minute of time in RA and 6 arcmin in Dec. The RA of the first observation is correct, while the declination of the second is correct. Unfortunately, the position JH adopted for the GC carries the RA of the second, and a Dec 10 arcmin further on north. I think he meant to use only the second observation (he notes that the first observation refers to "A double star in the southern part ..."), so the incorrect Dec must be a transcription or typographical error. Once these errors are corrected, though, N6811 turns out to be quite a nice cluster, ten or twelve arcmin across, with perhaps a hundred stars, many of the 10th and 11th magnitudes. - Dr. Harold G. Corwin, Jr. |