Platais 8
(MWSC 1629; OCSN 251)
0.98
UTI
0.88
CN
1.0
Cdens
1.0
CC3
1.0
Clit
1.0
Cdup
Radius (P>50% members)
176.1 [arcmin]
- CN 0.88 Rich
- Cdens 1.0 Very dense
- CC3 1.0 Very high quality
- Clit 1.0 Very well-studied
- Cdup 1.0 Unique
Overview
Platais 8 is a rich, very dense object of very high C3 quality. Its parallax locates it at a very 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 mass parameters (see Parameters). It is very well-studied in the literature.
Very close
Low extinction
Near-solar metallicity
Young
Data
| Reference | Year | RA [deg] | DEC [deg] | Plx [mas] | pmRA [mas/yr] | pmDE [mas/yr] | Rv [km/s] |
|---|---|---|---|---|---|---|---|
| UCC | â | 137.052 | -58.656 | 7.34 | -15.479 | 14.008 | 20.535 |
| Li et al. | 2025 | 136.718 | -58.685 | 7.415 | -15.596 | 14.474 | â |
| Almeida et al. | 2025 | 136.864 | -58.361 | â | â | â | â |
| Alfonso et al. | 2024 | 137.467 | -56.954 | 7.352 | -16.213 | 13.769 | â |
| Hunt & Reffert | 2024 | 136.895 | -59.309 | 7.427 | -16.238 | 13.743 | 18.521 |
| Cavallo et al. | 2024 | 137.331 | -57.241 | 7.435 | â | â | â |
| Hunt & Reffert | 2023 | 136.895 | -59.309 | 7.427 | -16.238 | 13.743 | 18.521 |
| Almeida et al. | 2023 | 137.221 | -58.381 | â | â | â | â |
| Qin et al. | 2023 | 137.04 | -59.36 | 7.45 | -16.31 | 13.38 | 22.14 |
| Just et al. | 2023 | 136.871 | -59.157 | â | â | â | â |
| He et al. | 2022 | 136.828 | -58.473 | 7.358 | -15.744 | 14.079 | â |
| Dias et al. | 2021 | 136.864 | -58.361 | 7.409 | -15.651 | 14.512 | 21.173 |
| Cantat-Gaudin et al. | 2020 | 136.718 | -58.685 | 7.415 | -15.596 | 14.474 | â |
| Cantat-Gaudin & Anders | 2020 | 136.718 | -58.685 | 7.415 | -15.596 | 14.474 | â |
| Soubiran et al. | 2018 | 136.718 | -58.685 | â | â | â | 20.64 |
| Cantat-Gaudin et al. | 2018 | 136.718 | -58.685 | 7.415 | -15.596 | 14.474 | â |
| Yen et al. | 2018 | 136.687 | -58.987 | 7.45 | -15.83 | 14.73 | â |
| Kharchenko et al. | 2016 | 136.871 | -59.157 | â | â | â | â |
| Kharchenko et al. | 2013 | 136.875 | -59.16 | â | -15.0 | 14.8 | 17.3 |
| Gozha et al. | 2012 | 137.375 | -59.128 | â | â | â | â |
| Piskunov et al. | 2008 | 136.946 | -59.137 | â | â | â | â |
| Kharchenko et al. | 2007 | 137.37 | -59.13 | â | 3.0 | â | 17.32 |
| Piskunov et al. | 2007 | 136.946 | -59.137 | â | â | â | â |
| van den Bergh | 2006 | 137.375 | -59.128 | â | â | â | â |
| Kharchenko et al. | 2005 | 136.95 | -59.14 | â | -15.83 | 14.8 | 17.32 |
| Dias et al. | 2002 | 137.375 | -59.128 | â | -15.67 | 15.83 | 17.32 |
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 | 0.15 | 0.22 | â | 38 | -0.053 | â | â | â |
| Almeida et al. | 2025 | 0.13 | 0.19 | â | 37 | â | 113 | â | â |
| Alfonso et al. | 2024 | 0.13 | 0.14 | â | 29 | -0.050 | â | â | â |
| Hunt & Reffert | 2024 | â | â | â | â | â | 44* | â | â |
| Cavallo et al. | 2024 | 0.13 | 0.64 | â | 49 | 0.160 | â | â | â |
| Hunt & Reffert | 2023 | 0.13 | 0.18 | 0.72 | 31 | â | â | â | â |
| Almeida et al. | 2023 | 0.14 | 0.06 | â | 51 | 0.153 | 129* | 0.36 | â |
| Qin et al. | 2023 | 0.15 | 0.25 | â | 35 | â | â | â | â |
| Just et al. | 2023 | â | â | â | 56 | â | 12 | â | â |
| He et al. | 2022 | â | 0.05 | â | 32 | â | â | â | â |
| Dias et al. | 2021 | 0.13 | 0.19 | â | 37 | -0.050 | â | â | â |
| Cantat-Gaudin et al. | 2020 | 0.13 | 0.14 | â | 30 | â | â | â | â |
| Cantat-Gaudin & Anders | 2020 | 0.13 | â | â | â | â | â | â | â |
| Soubiran et al. | 2018 | 0.13 | â | â | â | â | â | â | â |
| Cantat-Gaudin et al. | 2018 | 0.13 | â | â | â | â | â | â | â |
| Yen et al. | 2018 | 0.14 | 0.07 | â | 79 | â | â | â | â |
| Kharchenko et al. | 2016 | 0.14 | 0.00 | â | 56 | â | â | â | â |
| Kharchenko et al. | 2013 | 0.14 | 0.00 | â | 56 | -0.292 | â | â | â |
| Gozha et al. | 2012 | 0.13 | â | â | 60 | â | 1202 | â | â |
| Piskunov et al. | 2008 | 0.15 | 0.00 | â | 56 | â | 698* | â | â |
| Piskunov et al. | 2007 | 0.15 | 0.00 | â | 56 | â | 546 | â | â |
| van den Bergh | 2006 | 0.13 | â | â | 60 | â | â | â | â |
| Kharchenko et al. | 2005 | 0.15 | 0.00 | â | 56 | â | â | â | â |
| Dias et al. | 2002 | 0.13 | â | â | 60 | -0.296 | â | â | â |
(*): Indicates that this parameter is assigned more than one value in the corresponding reference.


Almeida et al. (2025)
Mass determination: good fit. Isochrone match: good fit. Gold sample.
Cavallo et al. (2024)
Gold sample.