UPK 28
0.77
UTI
0.6
CN
1.0
Cdens
0.75
CC3
0.75
Clit
1.0
Cdup
Stellar density (N50/rad)
14.5 [N/pc2]
- CN 0.6 Moderately populated
- Cdens 1.0 Very dense
- CC3 0.75 High quality
- Clit 0.75 Well-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 28 is a moderately populated, very dense object of high C3 quality. Its parallax locates it at a close distance, above the mid-plane, affected by high extinction. It is catalogued as a near-solar metallicity, intermediate-age cluster, but with a large variance across recent sources for the distance, absorption, age, and metallicity parameters (see Parameters). It is well-studied in the literature.
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 | 277.352 | -4.977 | 1.093 | 0.807 | -2.555 | -6.135 |
| Li et al. | 2025 | 277.352 | -4.974 | 1.109 | 0.772 | -2.511 | â |
| Almeida et al. | 2025 | 277.359 | -4.984 | â | â | â | â |
| Alfonso et al. | 2024 | 276.816 | -5.789 | 0.913 | 0.613 | -2.32 | â |
| Hunt & Reffert | 2024 | 277.362 | -4.982 | 1.11 | 0.827 | -2.589 | 10.616 |
| Cavallo et al. | 2024 | 277.367 | -4.97 | 1.105 | â | â | â |
| Hunt & Reffert | 2023 | 277.362 | -4.982 | 1.11 | 0.827 | -2.589 | 10.616 |
| Almeida et al. | 2023 | 277.378 | -5.026 | â | â | â | â |
| He et al. | 2022 | 277.36 | -4.977 | 1.09 | 0.857 | -2.559 | â |
| Tarricq et al. | 2022 | 277.346 | -4.977 | 1.089 | 0.871 | -2.558 | â |
| Dias et al. | 2021 | 277.359 | -4.984 | 1.1 | 0.778 | -2.504 | â |
| Cantat-Gaudin et al. | 2020 | 277.352 | -4.974 | 1.109 | 0.772 | -2.511 | â |
| Cantat-Gaudin & Anders | 2020 | 277.351 | -4.973 | 1.102 | 0.785 | -2.531 | â |
| Sim et al. | 2019 | 277.358 | -4.987 | â | 0.81 | -2.49 | 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 | 0.88 | 3.13 | 2.02 | 106 | 0.230 | 270 | 0.59 | â |
| Liu et al. | 2025 | 2.63 | 1.10 | â | 295 | â | â | â | â |
| Li et al. | 2025 | 0.52 | 2.85 | â | 802 | -0.169 | â | â | â |
| Almeida et al. | 2025 | 0.84 | 3.13 | â | 42 | â | 269 | â | â |
| Alfonso et al. | 2024 | 0.93 | 2.88 | â | 158 | 0.351 | â | â | â |
| Hunt & Reffert | 2024 | â | â | â | â | â | 469(1) | â | â |
| Cavallo et al. | 2024 | 1.00 | 3.74 | â | 29 | 0.230 | â | â | â |
| Hunt & Reffert | 2023 | 0.87 | 3.71 | 2.02 | 54 | â | â | â | â |
| Almeida et al. | 2023 | 0.88 | 3.25 | â | 29 | 0.162 | 270(1) | 0.59 | â |
| He et al. | 2022 | â | 4.00 | â | 28 | â | â | â | â |
| Tarricq et al. | 2022 | 0.91 | â | â | 191 | â | â | â | â |
| Dias et al. | 2021 | 0.84 | 3.13 | â | 42 | 0.351 | â | â | â |
| Cantat-Gaudin et al. | 2020 | 0.93 | 2.88 | â | 166 | â | â | â | â |
| Cantat-Gaudin & Anders | 2020 | 0.88 | â | â | â | â | â | â | â |
| Sim et al. | 2019 | 0.88 | â | â | 794 | â | â | â | â |
(N): Indicates that there are N extra values assigned to this parameter in the corresponding reference.
Liu et al. (2025)
Classified as hyperbolic encounter pair 390 along with UPK_27.
Palma et al. (2025)
Classified as optical pair P605, along with UPK_27.
Cavallo et al. (2024)
Gold sample.
Almeida et al. (2025)
Mass determination: intermediate fit. Isochrone match: intermediate fit. Silver sample.