HSC 1789

0.15 UTI

0.0

C_N

0.14

C_dens

0.5

C_C3

0.06

C_lit

1.0

C_dup

N_m (P>50%) 21

Core radius and density 2.2 [pc], 0.7 [pc^-2]

C3 classification BB

C_N 0.0 Sparse
C_dens 0.14 Very loose
C_C3 0.5 Intermediate quality
C_lit 0.06 Rarely studied
C_dup 1.0 Unique

📥 Members 📊 Colab 🔬 Bayestar19

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

Overview

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HSC 1789 is a sparse, very loose object of intermediate C3 quality. Its parallax locates it at a large 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 was recently reported in the literature.

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

⚠️ 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 Moderate extinction Near-solar metallicity Intermediate age

Cavallo et al. (2024)
Gold sample.

Hunt & Reffert (2024)
Classified as open cluster. CMD class: 0.35 (50th percentile).

Hunt & Reffert (2023)
Classified as open cluster. CMD class: 0.35 (50th percentile).

Data

🔍 Search references for HSC 1789 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–	110.085	-12.137	0.197	-0.946	0.636	111.348
Hu & Soubiran	2025	110.073	-12.11	–	–	–	–
Hunt & Reffert	2024	110.082	-12.129	0.194	-0.911	0.659	99.163
Cavallo et al.	2024	110.073	-12.11	0.193	–	–	–
Hunt & Reffert	2023	110.082	-12.129	0.194	-0.911	0.659	99.163

💡 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–	4.34	1.4	1.94	539	-0.455	251	–	–
Hu & Soubiran	2025	–	–	–	–	-0.290⁽⁵⁾	–	–	–
Hunt & Reffert	2024	4.34	1.40	1.94	539	–	251⁽¹⁾	–	–
Cavallo et al.	2024	3.08	2.14	–	617	-0.620	–	–	–
Hunt & Reffert	2023	4.34	1.40	1.94	538	–	–	–	–

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

Cluster	%	RA	DEC	Plx	pmRA	pmDE	Rv	UTI
CWNU 3156	80.0	110.09	-12.13	0.2	-0.96	0.64	103.81	0.04

💡 Note: The % column shows the percentage of members that HSC 1789 shares with each listed object.

Visualization

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