NGC 2420

(Melotte 69; Collinder 154; MWSC 1292; OCL 488; FoF 642)

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1.0 UTI
1.0
CN
1.0
Cdens
1.0
CC3
1.0
Clit
1.0
Cdup
N50 (P>50% members) 1207
Stellar density (N50/rad) 62.3 [N/pc2]
C3 classification AA
  • CN 1.0 Very rich
  • Cdens 1.0 Very dense
  • CC3 1.0 Very high quality
  • Clit 1.0 Very well-studied
  • Cdup 1.0 Unique
đŸ“Ĩ Members 📊 Colab đŸ”Ŧ Bayestar19 MOCAMOCA 🔍 CDS 🔍 Simbad 🔍 CDS (Îą, δ) 🔍 Simbad (Îą, δ)

Overview
ℹī¸
NGC 2420 is a very rich, very dense object of very high C3 quality. Its parallax locates it at a moderate distance, well above the mid-plane, affected by low extinction. It is catalogued as a massive, near-solar metallicity, old cluster, but with a large variance across recent sources for the metallicity parameter (see Parameters). It is very well-studied in the literature.

Note: This object contains blue stragglers according to at least one source.

Note: This object shares a very small percentage of members with a later reported entry. See table with shared members information.

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

Cavallo et al. (2024)
Gold sample.

Hunt & Reffert (2024)
Classified as open cluster. CMD class: 0.99 (50th percentile).

Rain et al. (2021)
Best fit with log(t)=9.3, Av=1.5 and solar metallicity.

Ahumada & Lapasset (2007)
Star 17 (WEBDA number) appears as a straggler in the diagrams of (1990AJ.....99.1504A) but is a non-member according to (1972A&A....20..425V). Other membership probabilities from the same reference: star R, 77%, star g, 90%, star 2206a, 87%. Stars 1116, 2206a, and g are cited as blue stragglers by (1994AJ....108.1828M) based on the photometry (1976AUBas.C......1B).

Data
🔍 Search references for NGC 2420 in: SciX Simbad
ℹī¸
Reference Year RA [deg] DEC [deg] Plx [mas] pmRA [mas/yr] pmDE [mas/yr] Rv [km/s]
UCC 99999– 114.603 21.577 0.383 -1.211 -2.044 73.593
Bijavara Seshashayana et al. 2025 114.563 21.583 – – – –
Otto et al. 2026 114.602 21.574 – -1.19 -2.12 74.4
Li et al. 2025 114.602 21.575 0.363 -1.19 -2.125 –
Guerco et al. 2025 115.0 21.6 0.41 -1.25 -1.99 74.4
Hu & Soubiran 2025 114.606 21.576 – – – –
Wei et al. 2025 114.603 21.576 0.399 -1.224 -2.042 –
Carrasco-Varela et al. 2025 114.861 21.514 – – – –
Almeida et al. 2025 114.605 21.572 – – – –
Zhang et al. 2024 114.602 21.574 – – – –
Hunt & Reffert 2024 114.602 21.574 0.39 -1.215 -2.039 72.165
Cavallo et al. 2024 114.606 21.576 0.391 – – –
Hunt & Reffert 2023 114.602 21.574 0.39 -1.215 -2.039 72.165
Cordoni et al. 2023 114.605 21.572 0.363 -1.202 -2.124 –
Just et al. 2023 114.587 21.569 – – – –
Jadhav & Subramaniam 2021 114.602 21.575 – – – –
Jaehnig et al. 2021 114.603 21.576 0.391 -1.192 -2.118 –
Rain et al. 2021 114.602 21.575 0.363 -1.19 -2.125 –
Dias et al. 2021 114.605 21.572 0.363 -1.202 -2.124 74.291
Spina et al. 2021 114.601 21.576 0.362 -1.195 -2.133 –
Cantat-Gaudin et al. 2020 114.602 21.575 0.363 -1.19 -2.125 –
Donor et al. 2020 114.596 21.567 – -1.14 -2.11 74.4
Zhong et al. 2020 114.602 21.575 – -1.19 -2.125 64.994
Cantat-Gaudin & Anders 2020 114.602 21.575 0.363 -1.19 -2.125 –
Liu & Pang 2019 114.607 21.579 0.366 -1.181 -2.129 –
Bossini et al. 2019 114.602 21.575 – – – –
Soubiran et al. 2018 114.602 21.575 – – – 74.22
Bica et al. 2019 114.603 21.573 – – – –
Cantat-Gaudin et al. 2018 114.602 21.575 0.363 -1.19 -2.125 –
Loktin & Popova 2017 114.6 21.573 – -2.547 -3.982 67.0
Kharchenko et al. 2016 114.587 21.569 – – – –
Dias et al. 2014 114.596 21.573 – -1.76 -2.38 –
Kharchenko et al. 2013 114.595 21.567 – -2.56 -3.83 67.0
Gozha et al. 2012 114.596 21.573 – – – –
Bukowiecki et al. 2011 114.604 21.58 – – – –
Kharchenko et al. 2007 114.6 21.57 – 0.04 – –
Ahumada & Lapasset 2007 114.6 21.567 – – – –
van den Bergh 2006 114.596 21.573 – – – –
Chen et al. 2003 114.593 21.569 – – – –
Dias et al. 2002 114.596 21.573 – -1.76 -2.38 73.57
Lynga 1987 114.613 21.577 – – – –
Sulentic et al. 1973 114.595 21.576 – – – –

💡 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] Bfrac BSS
UCC 99999– 2.55 0.095 0.13 2018 -0.202 2414 0.455 3
Bijavara Seshashayana et al. 2025 – 0.04 – 1740 -0.220(14) – – –
Otto et al. 2026 – – – 1738 -0.180(15) – – –
Li et al. 2025 2.44 0.18 – 2239 -0.203 – – –
Guerco et al. 2025 – – – 1740 -0.200 – – –
Hu & Soubiran 2025 – – – – -0.300(5) – – –
Wei et al. 2025 2.41 0.02 – 2630 0.000 2764 0.59 –
Carrasco-Varela et al. 2025 2.44 0.12 – 2223 -0.150 – – 3(1)
Almeida et al. 2025 2.44 0.12 – 2223 – 1876 – –
Zhang et al. 2024 – – – – -0.260(1) – – –
Hunt & Reffert 2024 – – – – – 3480(1) – –
Cavallo et al. 2024 2.32 0.10 – 2239 -0.020 – – –
Hunt & Reffert 2023 2.28 0.03 0.13 2249 – – – –
Cordoni et al. 2023 2.43 0.12 – 2223 -0.100 1571 0.32 4(1)
Just et al. 2023 – – – 2317 – 2032 – –
Spina et al. 2022 – – – – -0.190 – – –
Jadhav & Subramaniam 2021 2.58 0.04 – 1738 – 2970 – 2(1)
Jaehnig et al. 2021 2.57(1) – – – – – – –
Rain et al. 2021 2.55 0.13 – 1995 – – – 3
Dias et al. 2021 2.44 0.12 – 2223 -0.100 – – –
Spina et al. 2021 2.76 – – 1738 -0.185(20) – – –
Cantat-Gaudin et al. 2020 2.58 0.04 – 1738 – – – –
Kounkel et al. 2020 2.51 0.25 – 2042 – – – –
Donor et al. 2020 – – – – -0.190 – – –
Zhong et al. 2020 2.55(1) 0.19 – 9271 -0.293 – – –
Cantat-Gaudin & Anders 2020 2.55 – – – – – – –
Liu & Pang 2019 – – – 2510 -0.500 – – –
Bossini et al. 2019 2.57 0.19 – 1866 -0.050 – – –
Soubiran et al. 2018 2.55 – – – – – – –
Cantat-Gaudin et al. 2018 2.55 – – – – – – –
Loktin & Popova 2017 3.12 0.10 – 1127 – – – –
Kharchenko et al. 2016 2.88 0.03 – 2317 – – – –
Kharchenko et al. 2013 2.88 0.03 – 2317 -0.380 – – –
Bukowiecki et al. 2012 – – – – – 2414 – –
Gozha et al. 2012 2.48 – – 1995 -0.380 – – –
Bukowiecki et al. 2011 2.41(1) 0.00 – 1995 – – – –
Ahumada & Lapasset 2007 – 0.09 – 1122 – – – 5
van den Bergh 2006 3.08 0.09 – 1122 – – – –
Chen et al. 2003 3.08 0.09 – 1110 -0.260(1) – – –
Dias et al. 2002 2.48 0.13 – 1995 -0.380 – – –
Lynga 1987 2.30 0.00 – 3981 -0.610 – – –

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

Cluster % RA DEC Plx pmRA pmDE Rv UTI
Theia 6042 2.1 114.62 21.57 0.47 -1.13 -2.07 72.68 0.0

💡 Note: The % column shows the percentage of members that NGC 2420 shares with each listed object.

Visualization
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NGC 2420 UCC
NGC 2420 HUNT23
NGC 2420 CANTAT20
Galactocentric position diagram