UPK 552
(OCSN 315)
0.67
UTI
0.37
CN
1.0
Cdens
0.75
CC3
0.62
Clit
1.0
Cdup
Radius (P>50% members)
27.6 [arcmin]
- CN 0.37 Poorly populated
- Cdens 1.0 Very dense
- CC3 0.75 High quality
- Clit 0.62 Moderately studied
- Cdup 1.0 Unique
Overview
UPK 552 is a poorly populated, very dense object of high C3 quality. Its parallax locates it at a very close distance, above the mid-plane, affected by low extinction. It is catalogued as a low-mass, 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.
Very close
Low extinction
Low mass
Near-solar metallicity
Young
Data
| Reference | Year | RA [deg] | DEC [deg] | Plx [mas] | pmRA [mas/yr] | pmDE [mas/yr] | Rv [km/s] |
|---|---|---|---|---|---|---|---|
| UCC | – | 158.498 | -47.229 | 3.074 | -22.479 | 6.497 | 4.749 |
| Almeida et al. | 2025 | 158.547 | -47.243 | – | – | – | – |
| Alfonso et al. | 2024 | 158.395 | -47.18 | 3.049 | -22.519 | 6.595 | – |
| Cavallo et al. | 2024 | 158.908 | -47.225 | 3.169 | – | – | – |
| Hunt & Reffert | 2023 | 158.46 | -46.986 | 3.166 | -23.087 | 6.501 | 3.594 |
| Qin et al. | 2023 | 158.39 | -47.08 | 3.07 | -22.57 | 6.45 | 9.18 |
| He et al. | 2022 | 158.302 | -47.082 | 3.076 | -22.516 | 6.572 | – |
| Tarricq et al. | 2022 | 158.54 | -47.106 | 3.071 | -22.444 | 6.359 | – |
| Dias et al. | 2021 | 158.547 | -47.243 | 3.048 | -22.57 | 6.35 | 7.675 |
| Cantat-Gaudin et al. | 2020 | 158.509 | -47.263 | 3.056 | -22.634 | 6.34 | – |
| Sim et al. | 2019 | 158.704 | -47.287 | – | -22.45 | 6.31 | – |
💡 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 |
|---|---|---|---|---|---|---|---|---|---|
| Almeida et al. | 2025 | 0.32 | 0.13 | – | 192 | – | 45 | – | – |
| Alfonso et al. | 2024 | 0.33 | 0.00 | – | 75 | -0.040 | – | – | – |
| Cavallo et al. | 2024 | 0.33 | 0.36 | – | 65 | 0.380 | – | – | – |
| Hunt & Reffert | 2023 | 0.30 | 0.08 | 0.34 | 108 | – | – | – | – |
| Qin et al. | 2023 | 0.34 | 0.22 | – | 79 | – | – | – | – |
| He et al. | 2022 | – | 0.35 | – | 71 | – | – | – | – |
| Tarricq et al. | 2022 | 0.32 | – | – | 120 | – | – | – | – |
| Dias et al. | 2021 | 0.32 | 0.13 | – | 192 | -0.040 | – | – | – |
| Cantat-Gaudin et al. | 2020 | 0.33 | 0.00 | – | 117 | – | – | – | – |
| Sim et al. | 2019 | 0.34 | – | – | 89 | – | – | – | – |
💡 Note: The parameters are sometimes transformed from their original values to match the format of the columns shown here, see FAQ. The columns DAv, Bfr, BSS correspond to differential extinction, binary fraction, and blue stragglers, respectively. BSS values can be listed as fractions or integers.
Almeida et al. (2025): Mass determination: intermediate fit. Isochrone match: good fit.
Hunt & Reffert (2024): Classified as a moving group.
Cavallo et al. (2024): Gold sample.