| Open
Cluster
aka Melotte 205, Collinder 383, Raab 132, OCL 48 Integrated Visual Magnitude: 8.5 Apparent Diameter: 10' |
I call this nice little open cluster the "Little Circlet" after the very distinct circlet of stars found near its center. This circlet is quite reminiscent of the circlet of the constellation Pisces. Don't let the image below fool you -- this is a very nice cluster to look at. I found it to be much more pleasing than the widely dispersed nearby clusters M18 and M25. In fact, after observing these clusters on the same night I described NGC 6645 as "stunning!" in my notes.
In my 18-inch f/4.5 Dob, NGC 6645 appears as a relatively dense grouping of 10th to 13th magnitude stars, comprised of perhaps 50 total. The cluster isn't very regular in appearance, forming nice star chains and, of course, the circlet described above.
The field in a 6-inch at
50x. North is down and east is to the right.
| Millennium
Star Atlas Vol III Chart 1367
Sky Atlas 2000 Chart 16 Uranometria 2000 Vol II Chart 295 |
