Theia 101
0.22
UTI
0.0
CN
0.1
Cdens
0.38
CC3
0.3
Clit
1.0
Cdup
Stellar density (N50/rad)
0.5 [N/pc2]
- CN 0.0 Sparse
- Cdens 0.1 Very loose
- CC3 0.38 Low quality
- Clit 0.3 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 101 is a sparse, very loose object of low 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, intermediate-age cluster, but with a large variance across recent sources for the age and metallicity parameters (see Parameters). It was recently reported in the literature.
â ī¸ Warning: the low UTI value and no obvious signs of duplication (Cdup=1.0) indicate that this is quite probably an asterism, moving group, or artifact, and not a real open cluster.
Data
| Reference | Year | RA [deg] | DEC [deg] | Plx [mas] | pmRA [mas/yr] | pmDE [mas/yr] | Rv [km/s] |
|---|---|---|---|---|---|---|---|
| UCC | 99999â | 323.246 | 53.072 | 2.113 | 3.189 | -0.419 | -26.068 |
| Liu et al. | 2025 | 323.57 | 53.07 | 2.07 | 3.16 | -0.5 | -25.22 |
| Hu & Soubiran | 2025 | 323.455 | 53.155 | â | â | â | â |
| Zhang et al. | 2024 | 323.573 | 53.072 | â | â | â | â |
| Cavallo et al. | 2024 | 323.455 | 53.155 | 2.081 | â | â | â |
| Hunt & Reffert | 2023 | 323.573 | 53.072 | 2.075 | 3.158 | -0.497 | -25.22 |
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 | 0.48 | 0.73 | 0.98 | 135 | 0.076 | â | â | â |
| Liu et al. | 2025 | 0.73 | 0.31 | â | 81 | â | â | â | â |
| Hu & Soubiran | 2025 | â | â | â | â | -0.150(5) | â | â | â |
| Zhang et al. | 2024 | â | â | â | â | 0.076(1) | â | â | â |
| Cavallo et al. | 2024 | 0.48 | 0.73 | â | 617 | 0.390 | â | â | â |
| Hunt & Reffert | 2023 | 0.45 | 0.74 | 0.98 | 135 | 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 tidal capture (resonant trapping binary) 316 along with OCSN_28, and of multiple system 78 along with OCSN_28 and OCSN_27.
Palma et al. (2025)
Part of multiple system G239, along with Theia_248, OCSN_28 and OCSN_27.
Cavallo et al. (2024)
Gold sample.
Hunt & Reffert (2024)
Classified as a moving group.