UPK 4
0.82
UTI
0.7
CN
1.0
Cdens
1.0
CC3
0.7
Clit
1.0
Cdup
Radius (P>50% members)
15.8 [arcmin]
- CN 0.7 Moderately populated
- Cdens 1.0 Very dense
- CC3 1.0 Very high quality
- Clit 0.7 Moderately studied
- Cdup 1.0 Unique
Overview
UPK 4 is a moderately populated, very dense object of very high C3 quality. Its parallax locates it at a close distance, below the mid-plane, affected by moderate extinction. It is catalogued as a near-solar metallicity, intermediate-age cluster, but with a large variance across recent sources for the age parameter (see Parameters). It is moderately studied in the literature.
Close
Moderate extinction
Near-solar metallicity
Intermediate age
Data
| Reference | Year | RA [deg] | DEC [deg] | Plx [mas] | pmRA [mas/yr] | pmDE [mas/yr] | Rv [km/s] |
|---|---|---|---|---|---|---|---|
| UCC | â | 281.349 | -23.776 | 1.257 | -2.009 | -6.408 | 10.208 |
| Li et al. | 2025 | 281.361 | -23.764 | 1.239 | -2.009 | -6.373 | â |
| Almeida et al. | 2025 | 281.355 | -23.783 | â | â | â | â |
| Alfonso et al. | 2024 | 281.35 | -23.777 | 1.222 | -2.022 | -6.418 | â |
| Hunt & Reffert | 2024 | 281.387 | -23.766 | 1.265 | -2.028 | -6.408 | 9.351 |
| Cavallo et al. | 2024 | 281.335 | -23.812 | 1.266 | â | â | â |
| Hunt & Reffert | 2023 | 281.387 | -23.766 | 1.265 | -2.028 | -6.408 | 9.351 |
| He et al. | 2022 | 281.401 | -23.704 | 1.243 | -2.022 | -6.425 | â |
| Tarricq et al. | 2022 | 281.321 | -23.827 | 1.236 | -2.021 | -6.401 | â |
| Dias et al. | 2021 | 281.355 | -23.783 | 1.24 | -2.021 | -6.391 | â |
| Cantat-Gaudin et al. | 2020 | 281.361 | -23.764 | 1.239 | -2.009 | -6.373 | â |
| Cantat-Gaudin & Anders | 2020 | 281.357 | -23.768 | 1.245 | -2.023 | -6.384 | â |
| Sim et al. | 2019 | 281.373 | -23.744 | â | -2.03 | -6.4 | 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 |
|---|---|---|---|---|---|---|---|---|---|
| Li et al. | 2025 | 0.70 | 1.25 | â | 535 | 0.042 | â | â | â |
| Almeida et al. | 2025 | 0.77 | 1.39 | â | 252 | â | 236 | â | â |
| Alfonso et al. | 2024 | 0.83 | 1.04 | â | 467 | 0.035 | â | â | â |
| Hunt & Reffert | 2024 | â | â | â | â | â | 355* | â | â |
| Cavallo et al. | 2024 | 0.79 | 1.39 | â | 347 | 0.270 | â | â | â |
| Hunt & Reffert | 2023 | 0.75 | 1.24 | 1.54 | 157 | â | â | â | â |
| He et al. | 2022 | â | 1.85 | â | 50 | â | â | â | â |
| Tarricq et al. | 2022 | 0.81 | â | â | 288 | â | â | â | â |
| Dias et al. | 2021 | 0.77 | 1.39 | â | 252 | 0.035 | â | â | â |
| Cantat-Gaudin et al. | 2020 | 0.83 | 1.04 | â | 275 | â | â | â | â |
| Cantat-Gaudin & Anders | 2020 | 0.79 | â | â | â | â | â | â | â |
| Sim et al. | 2019 | 0.78 | â | â | 282 | â | â | â | â |
(*): Indicates that this parameter is assigned more than one value in the corresponding reference.
Almeida et al. (2025)
Mass determination: intermediate fit. Isochrone match: good fit.
Cavallo et al. (2024)
Gold sample.