RSG2

(TRSG 2; Alessi 84)

0.43 UTI

0.57

C_N

0.33

C_dens

1.0

C_C3

0.13

C_lit

1.0

C_dup

N_m (P>50%) 65

Core radius and density 1.8 [pc], 1.7 [pc^-2]

C3 classification AA

C_N 0.57 Moderately populated
C_dens 0.33 Loose
C_C3 1.0 Very high quality
C_lit 0.13 Rarely studied
C_dup 1.0 Unique

📥 Members 📊 Colab 🔬 Bayestar19

MOCA 🔍 CDS 🔍 Simbad 🔍 CDS (α, δ) 🔍 Simbad (α, δ)

Overview

ℹ️

RSG2 is a moderately populated, loose 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 near-solar metallicity, intermediate-age cluster, but with a large variance across recent sources for the metallicity parameter (see Parameters). It is rarely studied in the literature.

Note: This object shares a large percentage of members with 2 later reported entries. See table with shared members information.

Very close Low extinction Near-solar metallicity Intermediate age

Cavallo et al. (2024)
Gold sample.

Hunt & Reffert (2024)
Classified as moving group. CMD class: 1.00 (50th percentile).

Hunt & Reffert (2023)
Classified as open cluster. CMD class: 1.00 (50th percentile).

Bica et al. (2019)
List of clusters and alike reported by B. Alessi.

Data

🔍 Search references for RSG2 in: SciX Simbad

ℹ️

Reference	Year	RA [deg]	DEC [deg]	Plx [mas]	pmRA [mas/yr]	pmDE [mas/yr]	Rv [km/s]
UCC	99999–	110.724	55.284	5.043	-2.844	-31.209	10.89
Yang et al.	2025	110.51	55.385	–	–	–	–
Zhang et al.	2024	110.51	55.384	–	–	–	–
Cavallo et al.	2024	111.316	54.892	5.044	–	–	–
Hunt & Reffert	2023	110.51	55.384	5.037	-3.12	-31.447	8.742
Bica et al.	2019	110.725	55.282	–	–	–	–
Roser et al.	2016	110.58	54.7	–	-3.02	-28.8	–

💡 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]	B_frac	BSS
UCC	99999–	0.2	0.13	0.31	120	0.112	–	–	–
Yang et al.	2025	–	–	–	118	-0.040⁽³⁾	–	–	–
Zhang et al.	2024	–	–	–	–	0.112⁽¹⁾	–	–	–
Cavallo et al.	2024	0.20	0.46	–	123	0.280	–	–	–
Hunt & Reffert	2023	0.20	0.07	0.31	117	–	–	–	–
Roser et al.	2016	0.20	0.13	–	126	–	–	–	–

(N): Indicates that there are N extra values assigned to this parameter in the corresponding reference.

Cluster	%	RA	DEC	Plx	pmRA	pmDE	Rv	UTI
OCSN 304	100.0	110.72	55.28	5.04	-2.84	-31.22	10.76	0.01
CWNU 1128	69.2	110.61	55.28	5.04	-2.74	-31.14	11.02	0.0

💡 Note: The % column shows the percentage of members that RSG2 shares with each listed object.

Visualization

ℹ️

1 2