Theia 54
0.55
UTI
0.25
CN
1.0
Cdens
1.0
CC3
0.25
Clit
1.0
Cdup
Stellar density (N50/rad)
12.1 [N/pc2]
- CN 0.25 Poorly populated
- Cdens 1.0 Very dense
- CC3 1.0 Very high quality
- Clit 0.25 Poorly 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
Theia 54 is a poorly populated, 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, very young cluster, but with a large variance across recent sources for the absorption parameter (see Parameters). It is poorly studied in the literature.
Note: This object shares a large percentage of members with a later reported entry. 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 | 74.2 | 30.327 | 6.325 | 4.508 | -24.66 | 13.89 |
| Liu et al. | 2025 | 74.0 | 30.42 | 6.36 | 4.4 | -25.13 | 17.37 |
| Cavallo et al. | 2024 | 75.489 | 30.105 | 6.359 | â | â | â |
| Hunt & Reffert | 2023 | 73.999 | 30.416 | 6.357 | 4.403 | -25.133 | 17.369 |
| He et al. | 2022 | 74.871 | 29.925 | 6.376 | 4.139 | -25.168 | 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 | 0.15 | 0.36 | 1.1 | 7 | 0.180 | â | â | â |
| Liu et al. | 2025 | 0.15 | 0.06 | â | 8 | â | â | â | â |
| Cavallo et al. | 2024 | 0.15 | 1.08 | â | 13 | 0.180 | â | â | â |
| Hunt & Reffert | 2023 | 0.15 | 0.42 | 1.10 | 4 | â | â | â | â |
| He et al. | 2022 | â | 0.30 | â | 6 | â | â | â | â |
Liu et al. (2025)
Classified as primordial binary cluster 346 along with CWNU_1129, and of multiple system 35 along with Theia_71, HSC_1438, CWNU_1129, HSC_1426 and Theia_66.
Palma et al. (2025)
Part of multiple system G31, along with Theia_66 and CWNU_1129.
Cavallo et al. (2024)
Gold sample.
Hunt & Reffert (2024)
Classified as a moving group.