Ruprecht 163

(MWSC 1886)

0.23 UTI

0.0

C_N

0.03

C_dens

0.62

C_C3

0.26

C_lit

1.0

C_dup

N_m (P>50%) 18

Core radius and density 2.7 [pc], 0.1 [pc^-2]

C3 classification AC

C_N 0.0 Sparse
C_dens 0.03 Very loose
C_C3 0.62 Intermediate quality
C_lit 0.26 Poorly studied
C_dup 1.0 Unique

📥 Members 📊 Colab 🔬 Bayestar19

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

Overview

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Ruprecht 163 is a sparse, very loose object of intermediate C3 quality. Its parallax locates it at a close^* distance, below the mid-plane, affected by low extinction. It is catalogued as a near-solar metallicity, old cluster, but with a large variance across recent sources for the age parameter (see Parameters). It is poorly studied in the literature.

(*): The parallax distance estimate (~0.94 kpc) differs significantly from the median photometric distance (~3.02 kpc).

⚠️ Warning: the low UTI value and no obvious signs of duplication (C_dup=1.0) indicate that this is quite probably an asterism, moving group, or artifact, and not a real open cluster.

Distant Low extinction Near-solar metallicity Old

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).

Data

🔍 Search references for Ruprecht 163 in: SciX Simbad

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Reference	Year	RA [deg]	DEC [deg]	Plx [mas]	pmRA [mas/yr]	pmDE [mas/yr]	Rv [km/s]
UCC	99999–	166.198	-67.922	1.061	-5.848	0.066	13.785
Hu & Soubiran	2025	165.791	-67.617	–	–	–	–
Cavallo et al.	2024	165.791	-67.617	1.043	–	–	–
Hunt & Reffert	2023	166.172	-67.998	1.042	-5.825	0.139	16.195
Just et al.	2023	166.215	-67.939	–	–	–	–
Sampedro et al.	2017	166.213	-67.95	–	-6.58	4.3	–
Kharchenko et al.	2016	166.215	-67.939	–	–	–	–
Dias et al.	2014	166.212	-67.95	–	-6.94	3.5	–
Kharchenko et al.	2013	166.222	-67.943	–	-12.26	6.7	–
Dias et al.	2002	166.213	-67.95	–	-12.26	6.7	–
Lynga	1987	166.196	-67.933	–	–	–	–

💡 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–	3.02	0.98	0.82	2317	0.025	462	–	–
Hu & Soubiran	2025	–	–	–	–	-0.080⁽⁵⁾	–	–	–
Cavallo et al.	2024	0.96	0.39	–	617	0.130	–	–	–
Hunt & Reffert	2023	0.91	0.38	0.82	374	–	–	–	–
Just et al.	2023	–	–	–	2317	–	462	–	–
Kharchenko et al.	2016	3.02	0.98	–	2317	–	–	–	–
Kharchenko et al.	2013	3.02	0.98	–	2317	–	–	–	–
Dias et al.	2002	3.02	0.98	–	2317	–	–	–	–

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

Visualization

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