Pazmino's Cluster (Stock 23)

Stock 23
Stock 23: Section of DSS2 [147]

History

This star cluster was discovered in the second half of the 1950s by the German astronomer Jürgen Stock and first appeared in the first edition of the «Catalogue of Star Clusters and Associations» in 1958. [570] Jürgen Stock was later responsible for selecting the sites of the observatories on Cerro Tololo and La Silla in Chile. [571]

Sometimes you will also find the term «Pazmino's Cluster», which goes back to an article by John Pazmino in the March 1978 issue of «Sky & Telescope».

Physical Properties

Some sources refer to Stock 23 as an asterism and not a true cluster, as the brighter stars have different parallaxes and proper motions (see table 1). However, a study of the 3D morphology using Gaia EDR3 data revealed that Stock 23 is an open cluster with a filamentary structure. The distance is given as 606.7 pc and the cluster of 78 stars with about 106 solar masses is moving towards us at -18.57 km/s. The age of the cluster is estimated to be -18.57 km/s. The age of the cluster is estimated to be -18.57 km/s. The age of the cluster is estimated at 94 million years. [573] Most scientific sources referenced in Simbad refer to an open cluster. Simbad gives an extent of 90 arcminutes for Stock 23, with the centre about 15 arcminutes north of the conspicuous V-shaped asterism. [145]

The one 9 mag star (HD 237090), which is conspicuously further away at 1136 parsecs, has a high radial velocity of 128.8 km/s away from us. Presumably it was ejected from the cluster due to gravitational interaction.

Data from Simbad, distances and proper motions based on Gaia EDR3 [145]
NameRA [hms]Dec [dms]vMagspTypePM RA [mas/y]PM Dec [mas/y]RV [km/s]PLX [mas]Dist [pc]
HD 2004003 16 10.818+60 06 57.417.54G2III-13.398-1.686-34.52.5105398
HD 2005303 16 17.370+60 02 7.10OB--28
HD 2009503 16 41.919+59 59 26.708.12A0V17.640-17.38314.1324242
HD 2013403 16 59.751+60 04 2.977.47B2.5IV-V-4.377-1.021-12.501.6648601
HD 23709003 15 10.928+59 54 42.809.03B0.5IV:nn1.263-0.807128.800.87991136
HD 23709103 15 16.751+59 54 49.189.3B1:V:nnep-0.200-2.8577.605.1230
HD 23709703 15 58.799+60 12 1.719.03F6IV53.002-101.384-5.407.1175140
HD 23710403 16 45.559+60 05 6.769.05F6IV-25.6299.943-146.3699157
HD 23710603 16 55.226+60 04 41.929.81A0-4.1371.9391.973507

The cluster is embedded in a faint H-II region (Sh 2-202, LBN 676), crossed by some dark clouds (LDN 1383, 1385). About three degrees west is the well-known Soul Nebula (IC 1848), which together with Heart Nebula (IC 1805) is a popular target for astrophotographers.

Data from Simbad [145]
NameStock 23
Object TypeOpen Cluster
Right Ascension (J2000.0)03h 16m 18s
Declination (J2000.0)+60° 22' 37"
Parallaxes1.613 mas
Radialgeschwindigkeit-18.07 km/s
Redshift z-0.00006
Angular size90.5' × 90.5'
IdentifiersC 0312+598; Cl Stock 23; OCl 375.0; [KPR2004b] 41; [KPS2012] MWSC 0266

Finder Chart

Stock 23 is located in the constellation Camelopardalis, close to the two fourth magnitude stars CE and CS Camelopardalis. The IAU boundary line to the constellation Cassiopeia runs right through the middle of this cluster. On 14 November it is in opposition to the Sun and culminates at local midnight. The best observation time is from January to December, when the constellation, which is circumpolar in Central Europe, is highest in the sky.

Camelopardalis: Pazmino's Cluster (Stock 23)
Finder Chart Pazmino's Cluster (Stock 23)
always
12:39 | 76.3°
never
Charts created using SkySafari 6 Pro and STScI Digitized Sky Survey. Limiting magnitudes: Constellation chart ~6.5 mag, DSS2 close-ups ~20 mag. Times are shown for timezone UTC, Latitude 46.7996°, Longitude 8.23225°, Horizon height 5°, Date 2025-04-24. [149, 160]

Objects Within a Radius of 10°

References