OC 0640
0.00
UTI
0.64
CN
1.0
Cdens
1.0
CC3
0.31
Clit
0.0
Cdup
Radius (P>50% members)
2.2 [arcmin]
- CN 0.64 Moderately populated
- Cdens 1.0 Very dense
- CC3 1.0 Very high quality
- Clit 0.31 Poorly studied
- Cdup 0.0 Very likely duplicate
Overview
OC 0640 is a moderately populated, very dense 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 massive, near-solar metallicity, old cluster (see Parameters). It is poorly studied in the literature.
â ī¸ Warning: This is very likely a duplicate object, which shares a large percentage of members with at least one previously reported entry, and a moderate percentage with at least one entry reported in the same catalogue. See table with shared members information.
Relatively close
High extinction
Massive
Near-solar metallicity
Old
Data
| Reference | Year | RA [deg] | DEC [deg] | Plx [mas] | pmRA [mas/yr] | pmDE [mas/yr] | Rv [km/s] |
|---|---|---|---|---|---|---|---|
| UCC | â | 240.407 | -52.111 | 0.417 | -4.93 | -5.416 | -39.316 |
| Hu & Soubiran | 2025 | 240.416 | -52.126 | â | â | â | â |
| Hunt & Reffert | 2024 | 240.416 | -52.111 | 0.439 | -4.907 | -5.418 | -35.933 |
| Cavallo et al. | 2024 | 240.415 | -52.126 | 0.44 | â | â | â |
| Hunt & Reffert | 2023 | 240.416 | -52.111 | 0.439 | -4.907 | -5.418 | -35.933 |
| Hao et al. | 2022 | 240.415 | -52.116 | 0.425 | -4.921 | -5.422 | 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] | Bfr | BSS |
|---|---|---|---|---|---|---|---|---|---|
| Hu & Soubiran | 2025 | â | â | â | â | -0.270* | â | â | â |
| Hunt & Reffert | 2024 | â | â | â | â | â | 1934* | â | â |
| Cavallo et al. | 2024 | 1.71 | 3.59 | â | 1698 | -0.250 | â | â | â |
| Hunt & Reffert | 2023 | 2.14 | 3.75 | 2.40 | 701 | â | â | â | â |
| Hao et al. | 2022 | â | 4.58 | â | 1259 | 0.611 | â | â | â |
(*): Indicates that this parameter is assigned more than one value in the corresponding reference.
Cavallo et al. (2024)
Gold sample.