Credit: Aldo Zanetti
Astronomical and Imaging Data
| RA: | 16h 27m 13.86s |
| DEC: | -26° 01′ 24.6″ |
| MAG: | 9.01 |
| Diameter: | 7.4′ |
| Const: | Sco |
| OTA | Takahashi Epsilon 160ED |
| Focal Length | 536 |
| Camera | QHY600M |
| Site | Atacama, Chile |
| Sky Quality | Bortle 1 |
Useful Informations
NGC 6144 is a globular cluster located in the constellation Scorpius, relatively close to the bright star Antares and the much more famous globular cluster Messier 4 (M4).
You see it into the molecular cloud of Rho Ophiuchi, and that’s why the background sky color looks yellow. It’s an ancient, metal-poor, and sparse cluster.
Physical Properties and Location
NGC 6144 is a low-concentration globular cluster, classified as Shapley-Sawyer Concentration Class XI. Its stars are not as tightly packed as those in more centrally condensed clusters and harbor a handful of X-ray radiation sources This diffuse nature makes it challenging to observe due to contamination from background stars, particularly since it lies in a star-rich region of the Milky Way, partially obscured by the Rho Ophiuchi cloud complex.
- Age and Metallicity: NGC 6144 is estimated to be approximately 13 billion years old, placing it among the most ancient stellar systems in the galaxy. Its stars are extremely metal-poor, with a low abundance of elements heavier than hydrogen and helium. The cluster’s properties, like its color-magnitude diagram, show characteristics typical of other very metal-poor clusters such as M3 and M92.
- Distance: The cluster is located around 27,700 light-years from the Sun and is situated at a distance of about 7.8 kpc from the galactic center.
Scientific Significance
- Stellar Content: The cluster’s relatively low core density for a globular cluster is a notable feature. It contains a handful of X-ray radiation sources, which are a subject of ongoing study. The presence of blue straggler stars and RR Lyrae variable stars within the cluster provides insight into stellar dynamics and the age of the cluster.
- Galactic Interaction: The cluster’s orbital path through the galaxy and its proximity to the galactic plane suggest it has been subject to strong tidal forces from the Milky Way’s gravitational potential. This interaction may be a contributing factor to its sparse and extended structure.