HSC 2931
0.25
UTI
0.29
CN
0.6
Cdens
1.0
CC3
0.06
Clit
0.62
Cdup
Nm (P>50%)
29
Core radius and density
0.3 [pc], 3.0 [pc-2]
- CN 0.29 Poorly populated
- Cdens 0.6 Moderately dense
- CC3 1.0 Very high quality
- Clit 0.06 Rarely studied
- Cdup 0.62 Likely 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
HSC 2931 is a poorly populated, moderately dense object of very 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, very young cluster, but with a large variance across recent sources for the absorption parameter (see Parameters). It was recently reported in the literature.
Note: This is likely a unique object, which shares a moderate percentage of members with at least one previously 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 | 245.13 | -21.677 | 7.406 | -11.332 | -25.067 | -5.207 |
| Liu et al. | 2025 | 245.13 | -21.67 | 7.45 | -11.44 | -25.06 | -4.23 |
| Swiggum et al. | 2024 | 245.127 | -21.673 | 7.447 | -11.444 | -25.056 | -3.316 |
| Cavallo et al. | 2024 | 245.074 | -21.824 | 7.447 | â | â | â |
| Hunt & Reffert | 2023 | 245.127 | -21.673 | 7.447 | -11.444 | -25.056 | -4.234 |
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 | 0.13 | 0.51 | 0.52 | 7 | -0.260 | 33 | â | â |
| Liu et al. | 2025 | 0.19 | 0.34 | â | 14 | â | â | â | â |
| Swiggum et al. | 2024 | 0.13 | â | â | 6 | â | 33 | â | â |
| Cavallo et al. | 2024 | 0.13 | 1.58 | â | 8 | -0.260 | â | â | â |
| Hunt & Reffert | 2023 | 0.13 | 0.51 | 0.52 | 6 | â | â | â | â |
Liu et al. (2025)
Classified as primordial binary cluster 254 along with HSC_2919, and as primordial binary cluster 327 along with OCSN_100, and of multiple system 72 along with OCSN_96, HSC_2907, OCSN_98, OCSN_100 and HSC_2919.
Palma et al. (2025)
Part of multiple system G172, along with OCSN_98, HSC_2907, OCSN_96, HSC_2919 and OCSN_100.
Cavallo et al. (2024)
Gold sample.
Hunt & Reffert (2024)
Classified as moving group. CMD class: 0.99 (50th percentile).
Hunt & Reffert (2023)
Classified as open cluster. CMD class: 0.99 (50th percentile).