HSC 558

0.11 UTI

0.0

C_N

0.28

C_dens

0.25

C_C3

0.0

C_lit

1.0

C_dup

N₅₀ (P>50% members) 24

Stellar density (N₅₀/rad) 1.4 [N/pc²]

C3 classification DB

C_N 0.0 Sparse
C_dens 0.28 Loose
C_C3 0.25 Low quality
C_lit 0.0 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 558 is a sparse, loose object of low C3 quality. Its parallax locates it at a very close distance, above the mid-plane, affected by moderate extinction. It is catalogued as an old cluster (see Parameters). It was recently reported in the literature.

Note: This object shares a small percentage of members with at least one entry reported in the same catalogue. 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.

Very close Moderate extinction Old

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

Data

🔍 Search references for HSC 558 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–	288.021	39.097	3.87	-5.878	3.686	-27.427
Hunt & Reffert	2023	287.872	38.809	3.927	-6.002	3.902	-27.423

💡 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–	0.25	2.9	0.36	1972	–	–	–	–
Hunt & Reffert	2023	0.25	2.90	0.36	1972	–	–	–	–

Cluster	%	RA	DEC	Plx	pmRA	pmDE	Rv	UTI
HSC 569	16.0	289.3	40.62	3.44	-4.7	3.3	-22.33	0.16

💡 Note: The % column shows the percentage of members that HSC 558 shares with each listed object.

Visualization

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