SAI 90

(MWSC 1493)

0.20 UTI

0.0

C_N

0.13

C_dens

0.25

C_C3

0.32

C_lit

1.0

C_dup

N_m (P>50%) 24

Core radius and density 1.7 [pc], 0.6 [pc^-2]

C3 classification CC

C_N 0.0 Sparse
C_dens 0.13 Very loose
C_C3 0.25 Low quality
C_lit 0.32 Poorly studied
C_dup 1.0 Unique

📥 Members 📊 Colab 🔬 Bayestar19

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

Overview

ℹ️

SAI 90 is a sparse, very loose object of low C3 quality. Its parallax locates it at a moderate distance, below the mid-plane, affected by high extinction. It is catalogued as a very metal-rich, old cluster, but with a large variance across recent sources for the age parameter (see Parameters). It is poorly studied 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 High extinction Very metal-rich Old

Palma et al. (2025)
Classified as tidal capture (resonant trapping pair) P7, along with CWNU_1656.

Cavallo et al. (2024)
Silver sample.

Hunt & Reffert (2024)
Classified as open cluster. CMD class: 0.05 (50th percentile).

Hunt & Reffert (2023)
Classified as open cluster. CMD class: 0.05 (50th percentile).

Data

🔍 Search references for SAI 90 in: SciX Simbad

ℹ️

Reference	Year	RA [deg]	DEC [deg]	Plx [mas]	pmRA [mas/yr]	pmDE [mas/yr]	Rv [km/s]
UCC	99999–	127.018	-41.751	0.414	-4.849	4.335	–
Hunt & Reffert	2024	127.026	-41.754	0.418	-4.822	4.335	14.297
Cavallo et al.	2024	126.702	-41.79	0.418	–	–	–
Hunt & Reffert	2023	127.026	-41.754	0.418	-4.822	4.335	14.297
Just et al.	2023	127.018	-41.767	–	–	–	–
Bica et al.	2019	126.997	-41.767	–	–	–	–
Dias et al.	2018	–	–	–	-4.95	4.24	–
Sampedro et al.	2017	126.996	-41.769	–	–	–	–
Kharchenko et al.	2016	127.018	-41.767	–	–	–	–
Dias et al.	2014	126.996	-41.769	–	-1.91	1.81	–
Kharchenko et al.	2013	127.023	-41.77	–	-3.79	6.32	–
Glushkova et al.	2010	126.995	-41.769	–	–	–	–
Dias et al.	2002	126.996	-41.769	–	-1.91	1.81	–

💡 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–	2.74	3.22	2.69	1122	1.040	328	–	–
Hunt & Reffert	2024	2.21	2.72	2.69	13	–	248⁽¹⁾	–	–
Cavallo et al.	2024	2.56	2.99	–	38	1.040	–	–	–
Hunt & Reffert	2023	2.21	2.72	2.69	13	–	–	–	–
Just et al.	2023	–	–	–	1274	–	409	–	–
Kharchenko et al.	2016	3.11	3.28	–	1274	–	–	–	–
Kharchenko et al.	2013	3.11	3.28	–	1274	–	–	–	–
Glushkova et al.	2010	2.74	3.22	–	1122	–	–	–	–
Dias et al.	2002	2.74	3.22	–	1122	–	–	–	–

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

Visualization

ℹ️

1 2