Theia 874
0.21
UTI
0.32
CN
0.11
Cdens
0.38
CC3
0.13
Clit
1.0
Cdup
Nm (P>50%)
32
Core radius and density
1.6 [pc], 0.5 [pc-2]
- CN 0.32 Poorly populated
- Cdens 0.11 Very loose
- CC3 0.38 Low quality
- Clit 0.13 Rarely 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 874 is a poorly populated, very loose object of low C3 quality. Its parallax locates it at a close distance, above the mid-plane, affected by low extinction. It is catalogued as a low-mass, near-solar metallicity, intermediate-age cluster (see Parameters). It is rarely studied 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 | 87.583 | 34.162 | 1.361 | 2.037 | -6.447 | -10.573 |
| Yan et al. | 2026 | 87.572 | 34.228 | 1.358 | 2.051 | -6.419 | â |
| Zhang et al. | 2024 | 87.572 | 34.228 | â | â | â | â |
| Hunt & Reffert | 2024 | 87.572 | 34.228 | 1.358 | 2.051 | -6.419 | -8.716 |
| Cavallo et al. | 2024 | 87.225 | 34.646 | 1.359 | â | â | â |
| Hunt & Reffert | 2023 | 87.572 | 34.228 | 1.358 | 2.051 | -6.419 | -8.716 |
| Kounkel & Covey | 2019 | 87.847 | 33.277 | 1.298 | â | â | -15.064 |
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 | 0.7 | 0.545 | 0.67 | 320 | -0.007 | 42 | â | â |
| Yan et al. | 2026 | â | â | â | 319 | â | â | â | â |
| Zhang et al. | 2024 | â | â | â | â | -0.095(1) | â | â | â |
| Hunt & Reffert | 2024 | 0.69 | 0.48 | 0.67 | 320 | â | 42(1) | â | â |
| Cavallo et al. | 2024 | 0.71 | 0.69 | â | 234 | 0.080 | â | â | â |
| Hunt & Reffert | 2023 | 0.69 | 0.48 | 0.67 | 320 | â | â | â | â |
| Kounkel & Covey | 2019 | 0.77 | 0.61 | â | 442 | â | â | â | â |
(N): Indicates that there are N extra values assigned to this parameter in the corresponding reference.
Yan et al. (2026)
Number of WDs: expected from single-star evolution N=6, with probability of formation through binary evolution >=0.5 N=0.
Palma et al. (2025)
Classified as optical pair P428, along with HSC_1399.
Cavallo et al. (2024)
Gold sample.
Hunt & Reffert (2024)
Classified as open cluster. CMD class: 0.99 (50th percentile).
Hunt & Reffert (2023)
Classified as open cluster. CMD class: 0.99 (50th percentile).