Feinstein 1

(MWSC 1892)

0.67 UTI

0.7

C_N

0.37

C_dens

1.0

C_C3

0.65

C_lit

1.0

C_dup

N_m (P>50%) 91

Core radius and density 1.9 [pc], 1.9 [pc^-2]

C3 classification AA

C_N 0.7 Moderately populated
C_dens 0.37 Loose
C_C3 1.0 Very high quality
C_lit 0.65 Moderately studied
C_dup 1.0 Unique

📥 Members 📊 Colab 🔬 Bayestar19

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

Overview

ℹ️

Feinstein 1 is a moderately populated, loose object of very high C3 quality. Its parallax locates it at a moderate^* distance, near the mid-plane, affected by moderate extinction. It is catalogued as a massive, near-solar metallicity, very young cluster, but with a large variance across recent sources for the mass parameter (see Parameters). It is moderately studied in the literature.

(*): The parallax distance estimate (~2.58 kpc) differs significantly from the median photometric distance (~1.41 kpc).

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

Relatively close Moderate extinction Massive Near-solar metallicity Very young

Palma et al. (2025)
Classified as optical pair P327, along with CWNU_1730.

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).

Data

🔍 Search references for Feinstein 1 in: SciX Simbad

ℹ️

Reference	Year	RA [deg]	DEC [deg]	Plx [mas]	pmRA [mas/yr]	pmDE [mas/yr]	Rv [km/s]
UCC	99999–	166.332	-59.744	0.387	-6.692	1.753	-19.392
Hunt & Reffert	2024	166.294	-59.729	0.387	-6.674	1.758	-18.815
Cavallo et al.	2024	166.382	-59.759	0.388	–	–	–
Hunt & Reffert	2023	166.294	-59.729	0.387	-6.674	1.758	-18.815
Just et al.	2023	166.674	-59.816	–	–	–	–
Jaehnig et al.	2021	166.307	-59.733	0.392	-6.693	1.696	–
Dib et al.	2018	166.68	-59.82	–	–	–	–
Loktin & Popova	2017	166.485	-59.816	–	-3.55	-1.79	-13.4
Sampedro et al.	2017	166.483	-59.817	–	-3.42	-1.87	–
Joshi et al.	2016	166.68	-59.82	–	–	–	–
Kharchenko et al.	2016	166.674	-59.816	–	–	–	–
Dias et al.	2014	166.483	-59.817	–	-3.55	-1.79	–
Kharchenko et al.	2013	166.68	-59.82	–	-6.8	1.32	-13.4
Gozha et al.	2012	166.483	-59.817	–	–	–	–
Piskunov et al.	2008	166.755	-59.815	–	–	–	–
Kharchenko et al.	2007	166.48	-59.82	–	0.4	–	-13.43
Ahumada & Lapasset	2007	166.475	-59.817	–	–	–	–
van den Bergh	2006	166.48	-59.812	–	–	–	–
Kharchenko et al.	2005	166.75	-59.82	–	-6.57	2.26	-13.43
Kharchenko et al.	2003	166.5	-59.81	–	-6.12	3.9	–
Dias et al.	2002	166.483	-59.817	–	-3.55	-1.79	2.2
Lynga	1987	166.507	-59.827	–	–	–	1.0

💡 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–	1.41	1.315	2.02	13	-0.100	2716	–	0
Hunt & Reffert	2024	2.53	1.40	2.02	26	–	1358⁽¹⁾	–	–
Cavallo et al.	2024	2.21	1.31	–	19	-0.100	–	–	–
Hunt & Reffert	2023	2.53	1.40	2.02	26	–	–	–	–
Just et al.	2023	–	–	–	16	–	202	–	–
Jaehnig et al.	2021	2.57⁽¹⁾	–	–	–	–	–	–	–
Dib et al.	2018	1.41	–	–	16	–	–	–	–
Loktin & Popova	2017	0.99	1.26	–	10	–	–	–	–
Joshi et al.	2016	1.41	1.44	–	16	–	4074	–	–
Kharchenko et al.	2016	1.41	1.44	–	16	–	–	–	–
Kharchenko et al.	2013	1.41	1.44	–	16	–	–	–	–
Gozha et al.	2012	1.16	–	–	10	–	4074	–	–
Piskunov et al.	2008	1.16	1.32	–	9	–	–	–	–
Ahumada & Lapasset	2007	–	1.26	–	10	–	–	–	0
van den Bergh	2006	1.16	1.26	–	10	–	–	–	–
Kharchenko et al.	2005	1.16	1.32	–	9	–	–	–	–
Kharchenko et al.	2003	1.16	0.95	–	–	–	–	–	–
Dias et al.	2002	1.16	1.26	–	10	–	–	–	–
Lynga	1987	–	1.20	–	1	–	–	–	–

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

Cluster	%	RA	DEC	Plx	pmRA	pmDE	Rv	UTI
UBC 266	100.0	166.35	-59.75	0.38	-6.69	1.75	-16.86	0.24
CWWDL 2200	67.0	166.3	-59.72	0.39	-6.7	1.78	-19.39	0.02

💡 Note: The % column shows the percentage of members that Feinstein 1 shares with each listed object.

Visualization

ℹ️

1 2