UPK 5
0.56
UTI
0.67
CN
0.26
Cdens
0.75
CC3
0.56
Clit
1.0
Cdup
Nm (P>50%)
84
Core radius and density
2.0 [pc], 1.3 [pc-2]
- CN 0.67 Moderately populated
- Cdens 0.26 Loose
- CC3 0.75 High quality
- Clit 0.56 Moderately 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
UPK 5 is a moderately populated, loose object of high C3 quality. Its parallax locates it at a close distance, near the mid-plane, affected by low extinction. It is catalogued as a near-solar metallicity, young cluster, but with a large variance across recent sources for the absorption and metallicity parameters (see Parameters). It is moderately studied in the literature.
Data
| Reference | Year | RA [deg] | DEC [deg] | Plx [mas] | pmRA [mas/yr] | pmDE [mas/yr] | Rv [km/s] |
|---|---|---|---|---|---|---|---|
| UCC | 99999â | 273.246 | -18.358 | 1.771 | 0.671 | -8.437 | -6.368 |
| Yan et al. | 2026 | 273.21 | -18.326 | 1.764 | 0.682 | -8.447 | â |
| Li et al. | 2025 | 273.304 | -18.308 | 1.786 | 0.659 | -8.387 | â |
| Wei et al. | 2025 | 273.264 | -18.358 | 1.773 | 0.691 | -8.459 | â |
| Almeida et al. | 2025 | 273.323 | -18.299 | â | â | â | â |
| Alfonso et al. | 2024 | 273.206 | -18.371 | 1.731 | 0.679 | -8.464 | â |
| Hunt & Reffert | 2024 | 273.21 | -18.326 | 1.764 | 0.682 | -8.447 | -3.455 |
| Cavallo et al. | 2024 | 273.173 | -18.499 | 1.764 | â | â | â |
| Hunt & Reffert | 2023 | 273.21 | -18.326 | 1.764 | 0.682 | -8.447 | -3.455 |
| Tarricq et al. | 2022 | 273.279 | -18.248 | 1.768 | 0.684 | -8.449 | â |
| Dias et al. | 2021 | 273.323 | -18.299 | 1.773 | 0.654 | -8.374 | 7.814 |
| Cantat-Gaudin et al. | 2020 | 273.304 | -18.308 | 1.786 | 0.659 | -8.387 | â |
| Cantat-Gaudin & Anders | 2020 | 273.304 | -18.308 | 1.784 | 0.638 | -8.359 | â |
| Sim et al. | 2019 | 273.311 | -18.274 | â | 0.74 | -8.38 | 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 | 0.55 | 0.7 | 0.94 | 95 | 0.000 | 156 | 0.27 | â |
| Yan et al. | 2026 | â | â | â | 194 | â | â | â | â |
| Li et al. | 2025 | 0.56 | 0.70 | â | 95 | -0.048 | â | â | â |
| Wei et al. | 2025 | 0.75 | 0.95 | â | 68 | 0.000 | 192 | 0.27 | â |
| Almeida et al. | 2025 | 0.55 | 0.73 | â | 95 | â | 156 | â | â |
| Alfonso et al. | 2024 | 0.59 | 0.27 | â | 224 | 0.025 | â | â | â |
| Hunt & Reffert | 2024 | 0.53 | 0.63 | 0.94 | 83 | â | 146(1) | â | â |
| Cavallo et al. | 2024 | 0.54 | 1.33 | â | 62 | -0.280 | â | â | â |
| Hunt & Reffert | 2023 | 0.53 | 0.63 | 0.94 | 83 | â | â | â | â |
| Tarricq et al. | 2022 | 0.58 | â | â | 200 | â | â | â | â |
| Dias et al. | 2021 | 0.55 | 0.73 | â | 95 | 0.024 | â | â | â |
| Cantat-Gaudin et al. | 2020 | 0.59 | 0.27 | â | 195 | â | â | â | â |
| Cantat-Gaudin & Anders | 2020 | 0.55 | â | â | â | â | â | â | â |
| Sim et al. | 2019 | 0.55 | â | â | 100 | â | â | â | â |
(N): Indicates that there are N extra values assigned to this parameter in the corresponding reference.
Yan et al. (2026)
Number of WDs: expected from single-star evolution N=5, with probability of formation through binary evolution >=0.5 N=0.
Almeida et al. (2025)
Mass determination: good fit. Isochrone match: good fit.
Cavallo et al. (2024)
Gold sample.
Hunt & Reffert (2024)
Classified as open cluster. CMD class: 1.00 (50th percentile).
Hunt & Reffert (2023)
Classified as open cluster. CMD class: 1.00 (50th percentile).
Hu et al. (2021)
Ellipticities (core, all): e_core=0.5028, e_all=0.314.