Mamajek 1

(eta Chamaeleontis; MWSC 1535; OCSN 215)

0.84 UTI

0.45

C_N

1.0

C_dens

0.75

C_C3

1.0

C_lit

1.0

C_dup

C3 classification BA

Number of members (P>50%) 45

Radius (P>50% members) 83.2 [arcmin]

C_N 0.45 Poorly populated
C_dens 1.0 Very dense
C_C3 0.75 High quality
C_lit 1.0 Very well-studied
C_dup 1.0 Unique

📥 Members 📊 Colab 🔬 Bayestar19 🔍 CDS 🔍 Simbad 🔍 CDS (α, δ) 🔍 Simbad (α, δ)

Overview

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Mamajek 1 is a poorly populated, very dense object of high C3 quality. Its parallax locates it at a very close distance, near 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 is very well-studied in the literature.

Very close Low extinction Low mass Near-solar metallicity Very young

Almeida et al. (2025)
Mass determination: worst fit. Isochrone match: good fit.

Cavallo et al. (2024)
Gold sample.

Hunt & Reffert (2024)
Classified as a moving group.

Data

🔍 Search references for Mamajek 1 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	–	131.132	-78.912	9.984	-29.092	27.014	15.998
Almeida et al.	2025	130.568	-78.946	–	–	–	–
Celli et al.	2024	130.637	-78.963	–	–	–	–
Cavallo et al.	2024	131.041	-79.045	10.178	–	–	–
Hunt & Reffert	2023	130.564	-78.973	10.178	-30.186	26.756	16.388
Qin et al.	2023	130.64	-78.98	10.16	-29.31	27.48	16.0
Dias et al.	2021	130.568	-78.946	10.141	-29.451	27.134	16.746
Cantat-Gaudin et al.	2020	130.637	-78.963	10.13	-29.834	26.99	–
Cantat-Gaudin & Anders	2020	130.637	-78.963	10.13	-29.834	26.99	–
Soubiran et al.	2018	130.637	-78.963	–	–	–	16.69
Bica et al.	2019	130.484	-79.008	–	–	–	–
Cantat-Gaudin et al.	2018	130.637	-78.963	10.13	-29.834	26.99	–
Dias et al.	2014	130.525	-79.027	–	-4.27	4.52	–
Gozha et al.	2012	130.525	-79.027	–	–	–	–
Piskunov et al.	2008	130.536	-79.024	–	–	–	–
Kharchenko et al.	2007	130.53	-79.03	–	0.4	–	15.05
van den Bergh	2006	130.525	-79.027	–	–	–	–
Kharchenko et al.	2005	130.53	-79.03	–	-30.05	27.57	15.05
Dias et al.	2002	130.525	-79.027	–	-30.0	27.8	16.1

💡 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]	Bfr	BSS
Almeida et al.	2025	0.10	0.12	–	16	–	6	–	–
Celli et al.	2024	–	–	–	10	–	27	–	–
Cavallo et al.	2024	0.10	1.08	–	15	0.060	–	–	–
Hunt & Reffert	2023	0.10	0.34	0.34	4	–	–	–	–
Qin et al.	2023	0.10	0.12	–	8	–	–	–	–
Dias et al.	2021	0.10	0.12	–	16	-0.099	–	–	–
Cantat-Gaudin & Anders	2020	0.10	–	–	–	–	–	–	–
Soubiran et al.	2018	0.10	–	–	–	–	–	–	–
Cantat-Gaudin et al.	2018	0.10	–	–	–	–	–	–	–
Gozha et al.	2012	0.10	–	–	8	–	–	–	–
Piskunov et al.	2008	0.10	0.00	–	8	–	–	–	–
van den Bergh	2006	0.10	0.00	–	8	–	–	–	–
Kharchenko et al.	2005	0.10	0.00	–	8	–	–	–	–
Dias et al.	2002	0.10	0.00	–	8	–	–	–	–

Visualization

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