UPK 38

0.71 UTI

0.5

C_N

1.0

C_dens

0.75

C_C3

0.65

C_lit

1.0

C_dup

N₅₀ (P>50% members) 50

Stellar density (N₅₀/rad) 45.7 [N/pc²]

C3 classification AB

C_N 0.5 Moderately populated
C_dens 1.0 Very dense
C_C3 0.75 High quality
C_lit 0.65 Moderately studied
C_dup 1.0 Unique

📥 Members 📊 Colab 🔬 Bayestar19

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

Overview

ℹ️

UPK 38 is a moderately populated, very dense object of high C3 quality. Its parallax locates it at a close distance, near the mid-plane, affected by moderate extinction. It is catalogued as a near-solar metallicity, very young cluster, but with a large variance across recent sources for the metallicity parameter (see Parameters). It is moderately studied in the literature.

Close Moderate extinction Near-solar metallicity Very young

Palma et al. (2025)
Classified as optical pair (not dynamically associated) P168, along with Theia_12.

Cavallo et al. (2024)
Gold sample.

Almeida et al. (2025)
Mass determination: good fit. Isochrone match: good fit.

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

Data

🔍 Search references for UPK 38 in: SciX Simbad

ℹ️

Reference	Year	RA [deg]	DEC [deg]	Plx [mas]	pmRA [mas/yr]	pmDE [mas/yr]	Rv [km/s]
UCC	99999–	280.827	-1.639	1.697	-1.091	-5.254	-9.812
Li et al.	2025	280.829	-1.654	1.675	-1.102	-5.202	–
Almeida et al.	2025	280.83	-1.653	–	–	–	–
Alfonso et al.	2024	281.488	-2.085	1.54	0.024	-5.987	–
Celli et al.	2024	280.829	-1.654	–	–	–	–
Cavallo et al.	2024	280.789	-1.605	1.687	–	–	–
Hunt & Reffert	2023	280.82	-1.643	1.665	-1.173	-5.377	-7.026
Almeida et al.	2023	280.818	-1.648	–	–	–	–
He et al.	2022	280.839	-1.647	1.706	-1.073	-5.333	–
Dias et al.	2021	280.83	-1.653	1.65	-1.088	-5.243	–
Cantat-Gaudin et al.	2020	280.829	-1.654	1.675	-1.102	-5.202	–
Cantat-Gaudin & Anders	2020	280.829	-1.654	1.676	-1.179	-5.134	–
Sim et al.	2019	280.843	-1.654	–	-1.11	-5.27	–

💡 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–	0.59	2.2	1.82	12	-0.030	75	0.68	–
Li et al.	2025	0.48	2.20	–	18	-0.349	–	–	–
Almeida et al.	2025	0.59	2.20	–	12	–	94	–	–
Alfonso et al.	2024	0.60	2.09	–	14	-0.025	–	–	–
Celli et al.	2024	–	–	–	14	–	58	–	–
Cavallo et al.	2024	0.66	2.42	–	4	-0.030	–	–	–
Hunt & Reffert	2023	0.56	1.94	1.82	4	–	–	–	–
Almeida et al.	2023	0.57	2.32	–	11	-0.044	75⁽¹⁾	0.68	–
He et al.	2022	–	2.35	–	6	–	–	–	–
Dias et al.	2021	0.59	2.20	–	12	-0.025	–	–	–
Cantat-Gaudin et al.	2020	0.60	2.09	–	14	–	–	–	–
Cantat-Gaudin & Anders	2020	0.59	–	–	–	–	–	–	–
Sim et al.	2019	0.57	–	–	3	–	–	–	–

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

Visualization

ℹ️

1 2 3