Mamajek 2

(mu Oph Cluster; MWSC 2650)

0.76 UTI

0.75

C_N

1.0

C_dens

0.75

C_C3

0.65

C_lit

1.0

C_dup

N₅₀ (P>50% members) 110

Stellar density (N₅₀/rad) 11.3 [N/pc²]

C3 classification AB

C_N 0.75 Rich
C_dens 1.0 Very dense
C_C3 0.75 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

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Mamajek 2 is a rich, very dense object of high C3 quality. Its parallax locates it at a very close distance, above the mid-plane, affected by moderate 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 moderately 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 Moderate extinction Near-solar metallicity Intermediate age

Palma et al. (2025)
Part of multiple system G204, along with Theia_70 and HSC_95.

Cavallo et al. (2024)
Gold sample.

Data

🔍 Search references for Mamajek 2 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–	264.462	-7.925	5.046	-10.846	-20.718	-17.901
Zhang et al.	2024	264.36	-8.016	–	–	–	–
Hunt & Reffert	2024	264.36	-8.016	4.879	-10.069	-19.5	-16.534
Cavallo et al.	2024	265.835	-6.227	4.877	–	–	–
Hunt & Reffert	2023	264.36	-8.016	4.879	-10.069	-19.5	-16.534
He et al.	2022	264.347	-8.014	5.118	-11.05	-20.922	–
Bica et al.	2019	264.501	-8.107	–	–	–	–
Loktin & Popova	2017	264.495	-8.113	–	-0.956	-1.369	-18.5
Dias et al.	2014	264.5	-8.112	–	-3.85	-9.11	–
Gozha et al.	2012	264.5	-8.112	–	–	–	–
Kharchenko et al.	2007	264.49	-8.11	–	0.08	–	–
Dias et al.	2002	264.5	-8.112	–	-11.88	-20.81	-18.5

💡 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–	0.21	1.08	1.77	112	0.076	91	–	–
Zhang et al.	2024	–	–	–	–	-0.077⁽¹⁾	–	–	–
Hunt & Reffert	2024	–	–	–	–	–	91⁽¹⁾	–	–
Cavallo et al.	2024	0.21	1.08	–	74	0.230	–	–	–
Hunt & Reffert	2023	0.21	0.75	1.77	99	–	–	–	–
He et al.	2022	–	1.00	–	71	–	–	–	–
Loktin & Popova	2017	0.37	1.81	–	210	–	–	–	–
Gozha et al.	2012	0.16	–	–	126	–	–	–	–
Dias et al.	2002	0.16	2.48	–	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 216	100.0	264.46	-7.88	5.05	-10.8	-20.7	-17.9	0.04
CWWDL 14696	30.9	264.35	-7.95	5.11	-11.13	-20.88	-17.8	0.0

💡 Note: The % column shows the percentage of members that Mamajek 2 shares with each listed object.

Visualization

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