2008/02/04 by Rima Stonkute, R. Stonkutė, V. Vansevičius +11
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Barred spiral galaxy #Cluster (spacecraft) #Elliptical galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Grand design spiral galaxy #Interacting galaxy #Irregular galaxy #Physics #Spiral (railway) #Spiral galaxy #Star (game theory) #Star cluster #Stellar, planetary, and galactic studies #Unbarred spiral galaxy #astro-ph
paper · pdf · doi:10.1088/0004-6256/135/4/1482
20 pages, 6 figures, 2 tables, accepted for publication in AJ
arxiv created 2008/02/04 · openalex publication_date 2008/03/12 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We report the discovery of an extended globular-like star cluster, M 33-EC1, at the outer edge of the spiral galaxy M 33. The distance to the cluster is 890 kpc, and it lies at a projected distance of 12.5 kpc from the center of M 33. Old age (≳7 Gyr) and low metallicity ([M/H] ≲−1.4) are estimated on the basis of isochrone fits. Color–magnitude diagrams of stars, located in the cluster's area, and photometric and structural parameters of the cluster are presented. The cluster's luminosity ( M V = −6.6) and half-light radius ( r h = 20.3 pc) are comparable to those of the extended globular clusters, discovered in more luminous Local Group galaxies, the Milky Way and M 31. Extended globular clusters are suspected to be remnants of accreted dwarf galaxies, and the finding of such a cluster in the late-type dwarf spiral galaxy M 33 would imply a complex merging history in the past.