Credit: Armen Akopian
Astronomical and Imaging Data
| RA: | 17h 38m 36.60s |
| DEC: | -23° 54′ 34.2″ |
| MAG: | 9.45 |
| Diameter: | 4.9′ |
| Const: | Oph |
| OTA | CCF RC 250mm f/8 |
| Focal Length | 2000mm |
| Camera | QHYCCD QHY268 Pro M |
| Site | Rockwood, TX, United States |
| Sky Quality | Bortle 1 |
Useful Informations
NGC 6401 is a globular cluster located in the constellation Ophiuchus. It is a scientifically interesting object due to its location in the Galactic bulge region and its relatively high metallicity for a globular cluster, suggesting it is part of an inner-galaxy population.
Physical Properties & Location
- Distance: Located approximately 28,000 light-years from Earth.
- Apparent Magnitude: Its apparent magnitude is about 9.45, making it a faint but observable object with a moderate telescope.
- Concentration: NGC 6401 is a Shapley-Sawyer Concentration Class VI cluster, indicating a moderate level of central stellar concentration.
- Galactic Association: Due to its location, it is considered a Galactic bulge globular cluster, part of the oldest and most densely populated region of the Milky Way. Its kinematic properties confirm its status as an inner-halo cluster, with an orbit that takes it close to the Galactic Center.
Stellar Properties
- High Metallicity: NGC 6401 has a relatively high metallicity for a globular cluster, with an iron abundance ([Fe/H]) of approximately -1.03 dex. This is typical for globular clusters located in the Galactic bulge.
- Multiple Stellar Populations: Like many other globular clusters, NGC 6401 hosts multiple stellar populations, with distinct groups of stars showing variations in the abundance of light elements like nitrogen and sodium.
- Blue Straggler Stars: The cluster contains a population of blue straggler stars, which are older stars that appear younger and bluer than their neighbors.