PHOC 18
0.44
UTI
0.73
CN
0.23
Cdens
1.0
CC3
0.13
Clit
1.0
Cdup
Nm (P>50%)
96
Core radius and density
3.0 [pc], 1.1 [pc-2]
- CN 0.73 Moderately populated
- Cdens 0.23 Very loose
- CC3 1.0 Very high quality
- Clit 0.13 Rarely studied
- Cdup 1.0 Unique
đĨ Members
đ Colab
đŦ Bayestar19
MOCA
đ CDS
đ Simbad
đ CDS (Îą, δ)
đ Simbad (Îą, δ)
MOCA
đ CDS
đ Simbad
đ CDS (Îą, δ)
đ Simbad (Îą, δ)
Overview
PHOC 18 is a moderately populated, very loose object of very high C3 quality. Its parallax locates it at a moderate distance, near the mid-plane, affected by high extinction. It is catalogued as a near-solar metallicity, young cluster, but with a large variance across recent sources for the distance, age, and metallicity parameters (see Parameters). It is rarely studied in the literature.
Note: This object contains blue stragglers according to at least one source.
Note: This object shares a large percentage of members with 2 later reported entries. See table with shared members information.
Data
| Reference | Year | RA [deg] | DEC [deg] | Plx [mas] | pmRA [mas/yr] | pmDE [mas/yr] | Rv [km/s] |
|---|---|---|---|---|---|---|---|
| UCC | 99999â | 261.587 | -37.785 | 0.439 | 0.593 | -0.982 | -8.601 |
| Hunt & Reffert | 2024 | 261.597 | -37.747 | 0.441 | 0.57 | -0.98 | -19.506 |
| Cavallo et al. | 2024 | 261.568 | -37.777 | 0.44 | â | â | â |
| Hunt & Reffert | 2023 | 261.597 | -37.747 | 0.441 | 0.57 | -0.98 | -19.506 |
| Li et al. | 2023 | 261.584 | -37.791 | 0.44 | 0.53 | -0.98 | â |
| Hunt & Reffert | 2021 | 261.548 | -37.822 | 0.431 | 0.587 | -0.99 | â |
đĄ Note: The UCC values are estimated from its identified members.
| Reference | Year | Dist [kpc] | Av [mag] | DAv [mag] | Age [Myr] | [Fe/H] [dex] | Mass [Msun] | Bfrac | BSS |
|---|---|---|---|---|---|---|---|---|---|
| UCC | 99999â | 2.12 | 3.41 | 1.32 | 49 | 0.415 | 844 | â | 1 |
| Liu et al. | 2025 | 7.35 | 1.22 | â | 60 | â | â | â | â |
| Hunt & Reffert | 2024 | 2.12 | 3.41 | 1.32 | 49 | â | 844(1) | â | â |
| Cavallo et al. | 2024 | 2.65 | 3.54 | â | 43 | 0.970 | â | â | â |
| Hunt & Reffert | 2023 | 2.12 | 3.41 | 1.32 | 49 | â | â | â | â |
| Li et al. | 2023 | 1.91 | 2.00 | â | 1995 | -0.140 | â | â | 1(1) |
(N): Indicates that there are N extra values assigned to this parameter in the corresponding reference.
Liu et al. (2025)
Classified as tidal capture (resonant trapping binary) 105 along with CWNU_1303.
Palma et al. (2025)
Part of multiple system G38, along with CWNU_1303, BH_222, HSC_2889 and CWNU_2342.
Cavallo et al. (2024)
Gold sample.
Hunt & Reffert (2024)
Classified as open cluster. CMD class: 0.99 (50th percentile).
Hunt & Reffert (2023)
Classified as open cluster. CMD class: 0.99 (50th percentile).