Theia 1982

0.09 UTI

0.0

C_N

0.03

C_dens

0.38

C_C3

0.03

C_lit

1.0

C_dup

N_m (P>50%) 20

Core radius and density 3.1 [pc], 0.1 [pc^-2]

C3 classification BC

C_N 0.0 Sparse
C_dens 0.03 Very loose
C_C3 0.38 Low quality
C_lit 0.03 Rarely studied
C_dup 1.0 Unique

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

Overview

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Theia 1982 is a sparse, very loose object of low C3 quality. Its parallax locates it at a moderate distance, below the mid-plane, affected by low extinction. It is catalogued as a near-solar metallicity, intermediate-age cluster (see Parameters). It was recently reported in the literature.

⚠️ 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.

Relatively close Low extinction Near-solar metallicity Intermediate age

Palma et al. (2025)
Classified as optical pair P465, along with HSC_2353.

Cavallo et al. (2024)
Gold sample.

Hunt & Reffert (2024)
Classified as open cluster. CMD class: 0.93 (50th percentile).

Hunt & Reffert (2023)
Classified as open cluster. CMD class: 0.93 (50th percentile).

Data

🔍 Search references for Theia 1982 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–	156.952	-59.911	0.357	-7.208	2.99	–
Hunt & Reffert	2024	156.828	-59.942	0.356	-7.178	2.985	–
Cavallo et al.	2024	156.958	-59.938	0.356	–	–	–
Hunt & Reffert	2023	156.828	-59.942	0.356	-7.178	2.985	–

💡 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–	2.54	0.69	1.12	122	-0.320	104	–	–
Hunt & Reffert	2024	2.54	0.69	1.12	122	–	104⁽¹⁾	–	–
Cavallo et al.	2024	2.86	1.45	–	81	-0.320	–	–	–
Hunt & Reffert	2023	2.54	0.69	1.12	122	–	–	–	–

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

Visualization

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