37 Cluster (NGC 2169)

NGC 2169
NGC 2169: Section of the colorized DSS2 [147]


The cluster was probably first noticed by the Italian astronomer Giovanni Battista Hodierna, which published it in 1654. But this publication of his work was little noticed outside Sicily. [196] The cluster was rediscovered on 12 October 1782 by William Hershel using his little 6.2 inch telescope. He cataloged it as VIII 24 (class VIII = coarsely scattered clusters of stars) and noted: «A small cluster of pretty large white stars.» [463] In 1888 John L. E. Dreyer added the cluster with the designation NGC 2169 to his famous «New General Catalogue» [313]

In 1931 Per Collinder published his «Catalog of Open Galactic Clusters» where this cluster is listed as Collinder 83. [455] The cluster is also nicknamed «37 Cluster» due to its brightest members forming an asterism that looks like the number 37.

Physical Properties

The age of this rather young cluster is estimated to about 11 million years. [138]

Revised+Historic NGC/IC Version 22/9, © 2022 Dr. Wolfgang Steinicke [277]
Designation NGC 2169
Type OCL (I3p)
Right Ascension (J2000.0) 06h 08m 24.3s
Declination (J2000.0) +13° 57' 53"
Diameter 6 arcmin
Visual magnitude 5.9 mag
Metric Distance 1.032 kpc
Identification, Remarks WH VIII 24; h 379; GC 1361; OCL 481

Finder Chart

The open cluster NGC 2169 is located in the constellation of Orion, which is best visible from September to March.

Finder Chart 37 Cluster (NGC 2169)
37 Cluster (NGC 2169) in constellation Orion. Charts created using SkySafari 6 Pro and STScI Digitized Sky Survey. Limiting magnitudes: Constellation chart ~6.5 mag, DSS2 close-ups ~20 mag. [149, 160]

Visual Observation

400 mm Aperture: NGC 2169 offers a diverse and amusing sight with stars of different colors forming the shape of a «37» (or «λΣ» when upside down). One of the stars in the «3» is a binary star. — 400 mm f/4.5 Taurus Dobsonian, Hasliberg, 16. 12. 2023, SQM 21.2, Bernd Nies

Objects Within a Radius of 15°


  • [138] WEBDA, A site Devoted to Stellar Clusters in the Galaxy and the Magellanic Clouds; webda.physics.muni.cz
  • [147] Aladin Lite; aladin.unistra.fr/AladinLite
  • [149] SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
  • [160] The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
  • [196] Celestial Atlas by Curtney Seligman; cseligman.com/text/atlas.htm (2020-12-28)
  • [277] «Historische Deep-Sky Kataloge» von Dr. Wolfgang Steinicke; klima-luft.de/steinicke (2021-02-17)
  • [313] «A New General Catalogue of Nebulae and Clusters of Stars, being the Catalogue of the late Sir John F.W. Herschel, Bart., revised, corrected, and enlarged» Dreyer, J. L. E. (1888); Memoirs of the Royal Astronomical Society. 49: 1–237; Bibcode:1888MmRAS..49....1D
  • [455] «On Structural Properties of Open Galactic Clusters and their Spatial Distribution. Catalog of Open Galactic Clusters.» Collinder, Per; Annals of the Observatory of Lund, vol. 2, pp.B1-B46, 1931; Bibcode:1931AnLun...2....1C
  • [463] «Catalogue of one thousand new nebulae and clusters of stars» William Herschel, Philosophical Transactions of the Royal Society of London, 1 January 1786; DOI:10.1098/rstl.1786.0027