Open Clusters NGC 659 & NGC 663
History
According to Caroline Herschels never published «Zone Catalogue» she already discovered both clusters on 3 November 1783. She measured cluster GN 1827 following star δ Cassiopeiae by 17m 47s and 29' north (position of NGC 659). Cluster GN 1828 follows δ Cassiopeiae by 29m 39s and is 1° 2' north of it (position of NGC 663). She was using a small 4.2" f/6.4 Newtonian reflector with 30x magnification built in 1783. [277]
On 3 November 1787 William Herschel listed a «very compressed and rich cluster of stars» as VI 31 and wrote: «A beautiful cluster of pretty large stars near 15' diameter considerably rich.» In the same night he also listed a «coarsely scattered cluster of stars» as VIII 65 and noted: «A small cluster of small stars, not very rich. C. H. 1783» [464] Dreyer added these cluster as NGC 659 and NGC 663 to his «New General Catalogue» published in 1888. [313]
Physical Properties
Name | RA | Dec | Type | vMag | Dim | MD | Dreyer Description | Identification, Remarks |
---|---|---|---|---|---|---|---|---|
NGC 659 | 01 44 24.0 | +60 40 12 | OCL (III1p) | 7.9 | 6 | 1.938 | Cl, lRi, st B | WH VIII 65; GC 389; OCL 332 |
NGC 663 | 01 46 17.0 | +61 13 06 | OCL (III2m) | 7.1 | 15 | 1.952 | Cl, B, L, eRi, st pL | WH VI 31; GC 392; OCL 333 |
Finder Chart
The clusters NGC 659 and NGC 663 are located in the constellation Cassiopeia. The best viewing time is July to January when the in Europe circumpolar constellation is at its highest.