Credit: Armen Akopian
Astronomical and Imaging Data
| RA: | 15h 35m 28.52s |
| DEC: | -50° 39′ 34.8″ |
| MAG: | 9.61 |
| Diameter: | 3.0′ |
| Const: | Nor |
| OTA | ASA 1000RC |
| Focal Length | 6500mm |
| Camera | FLI PL16803 |
| Site | El Sauce, Chile |
| Sky Quality | Bortle 1 |
Useful Informations
NGC 5946 is a globular cluster located in the constellation Norma. It is a relatively faint and moderately concentrated cluster, whose scientific interest stems from its relatively high metallicity and its location within the Milky Way’s disk, rather than the halo.
Physical Properties & Location
- Distance: Located approximately 31,500 light-years from Earth.
- Apparent Magnitude: With an apparent magnitude of 10.7, it is a faint target requiring a medium-sized telescope to be observed visually.
- Concentration: NGC 5946 is a Class IV cluster on the Shapley–Sawyer Concentration Scale, indicating a moderate degree of central concentration.
- Galactic Association: Its orbit and position suggest that NGC 5946 is part of the Galactic disk, not the halo. This is a crucial characteristic, as most globular clusters are found in the halo.
Stellar Populations and Metallicity
- High Metallicity: NGC 5946 is considered a metal-rich globular cluster, with a metallicity of approximately -1.61 dex. While this is still metal-poor compared to the Sun, it is a high value for a globular cluster.
- RR Lyrae Variables: The cluster contains a population of RR Lyrae variable stars, which are commonly used to determine a cluster’s age and metallicity. NGC 5946 is a difficult cluster to study in this regard due to its low number of these variable stars and its location in a crowded field of view.