UPK 31

N_50

r_50

19.7

Summary

UPK 31 is a moderately populated, very dense object of intermediate C3 quality. It is located at a close distance from the Sun, near the mid-plane. It is well-studied in the literature.

This object shares a significant percentage of members with a later reported entry.

Search object in SciX | Simbad

Positions

Reference	RA	DEC	Plx	pmRA	pmDE	Rv
Sim et al. (2019)	285.952	-8.484	–	-0.32	1.21	–
Cantat-Gaudin et al. (2020)	285.913	-8.51	1.823	-0.28	1.216	–
Dias et al. (2021)	285.908	-8.574	1.827	-0.281	1.203	-16.265
Tarricq et al. (2022)	285.876	-8.442	1.858	-0.292	1.118	–
Hunt & Reffert (2023)	285.922	-8.483	1.822	-0.278	1.176	-17.605
Cavallo et al. (2024)	285.936	-8.38	1.828	–	–	–
Hunt & Reffert (2024)	285.922	-8.483	1.822	-0.278	1.176	-17.605
Alfonso et al. (2024)	285.957	-8.458	1.795	-0.294	1.169	–
Almeida et al. (2025)	285.908	-8.574	–	–	–	–

UCC	285.919	-8.458	1.841	-0.289	1.169	-16.336

Galactocentric position

How are the galactocentric plots generated?

Search coordinates in CDS | Simbad

Estimated members

1 2 3

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Fundamental parameters

Reference	Values
Sim et al. (2019)	`d_pc=540, log(age)=7.55`
Cantat-Gaudin et al. (2020)	`AVNN=0.61, DistPc=537.0, AgeNN=8.7`
Dias et al. (2021)	`Av=0.83, Dist=539, logage=8.791, [Fe/H]=0.006`
Tarricq et al. (2022)	`Dist=530, logAgeNN=8.7`
Hunt & Reffert (2023)	`AV50=0.643, diffAV50=1.104, MOD50=8.574, logAge50=8.629`
Cavallo et al. (2024)	`AV50=1.05, dMod50=8.7, logAge50=8.53, [Fe/H]50=0.13`
Hunt & Reffert (2024)	`MassJ=103.286, MassTot=181.896`
Alfonso et al. (2024)	`AV=0.60972, MOD=8.64999, logAge=8.81775, Z=0.00596`
Almeida et al. (2025)	`AV=0.83, Dist=539, logAge=8.791, MassRk=81.4`

Search coordinates in Bayestar19

Cluster region map

Objects with shared members

Cluster	%	RA	DEC	Plx	pmRA	pmDE	Rv	UTI
CWWDL 14601	71.4	285.91	-8.49	1.87	-0.3	1.17	-15.72	0.0