Alessi 257

0.05 UTI

0.26

C_N

1.0

C_dens

0.38

C_C3

0.0

C_lit

0.15

C_dup

N₅₀ (P>50% members) 26

Stellar density (N₅₀/rad) 25.6 [N/pc²]

C3 classification CB

C_N 0.26 Poorly populated
C_dens 1.0 Very dense
C_C3 0.38 Low quality
C_lit 0.0 Rarely studied
C_dup 0.15 Likely duplicate

📥 Members 📊 Colab 🔬 Bayestar19

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

Overview

ℹ️

Alessi 257 is a poorly populated, very dense object of low C3 quality. Its parallax locates it at a moderate distance, above the mid-plane, affected by high extinction. It is catalogued as a near-solar metallicity, intermediate-age cluster (see Parameters). It was recently reported in the literature.

⚠️ Warning: This is likely a duplicate object, which shares a large percentage of members with at least one previously reported entry. See table with shared members information.

Relatively close High extinction Near-solar metallicity Intermediate age

Data

🔍 Search references for Alessi 257 in: SciX Simbad

ℹ️

Reference	Year	RA [deg]	DEC [deg]	Plx [mas]	pmRA [mas/yr]	pmDE [mas/yr]	Rv [km/s]
UCC	99999–	192.351	-61.526	0.288	-7.257	-0.584	-27.485
Dias et al.	2026	192.336	-61.513	0.332	-7.285	-0.513	-17.391

💡 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–	2.82	3.45	–	131	0.136	–	–	–
Dias et al.	2026	2.82	3.45	–	131	0.136	–	–	–

Cluster	%	RA	DEC	Plx	pmRA	pmDE	Rv	UTI
Cru II Group	84.6	192.34	-61.52	0.31	-7.33	-0.64	-27.91	0.39

💡 Note: The % column shows the percentage of members that Alessi 257 shares with each listed object.

Visualization

ℹ️