Credit: Armen Akopian
Astronomical and Imaging Data
| RA: | 18h 59m 33.15s |
| DEC: | -36° 37′ 56.1″ |
| MAG: | 7.01 |
| Diameter: | 13.1′ |
| Const: | Sgr |
| OTA | Planewave CDK 24″ |
| Focal Length | 3974mm |
| Camera | QHYCCD QHY600 M |
| Site | El Sauce, Chile |
| Sky Quality | Bortle 1 |
Useful Informations
NGC 6723 is a globular cluster located in the constellation Sagittarius, positioned on the border with Corona Australis. It’s an important object for studying the formation of our galaxy’s central Galactic bulge due to its location and chemical properties.
Key Scientific Properties
- Age and Metallicity: NGC 6723 is an ancient cluster, estimated to be about 13 billion years old. Its stars are considered metal-intermediate, with a metallicity ([Fe/H]) of approximately -0.96. This value places it at the minimum of the bimodal metallicity distribution often seen in globular clusters, suggesting it may be a transitional system between metal-poor and metal-rich clusters. It also shows a characteristic enhancement of alpha-elements, such as oxygen and magnesium, which is a chemical signature consistent with early enrichment from massive, short-lived stars.
- Stellar Populations: A key scientific finding about NGC 6723 is the discovery of multiple stellar populations. A significant study found that the “primordial” first generation of stars accounts for only a very small fraction of the total stellar population. This is highly unusual and suggests a more complex formation history than previously thought, perhaps involving a very efficient process of star formation from enriched material.
- Structure and Dynamics: Classified as a Shapley-Sawyer Class VII cluster, NGC 6723 has a moderate concentration of stars, making it less dense than some of the more tightly packed clusters. It is located at a distance of about 28,400 light-years from Earth and has a mass of roughly 357,000 times the mass of the Sun.