FSR 584: Another new nearby globular cluster candidate

Bica et.al. have announced another nearby globular cluster candidate in the Milky Way:


Author: E. Bica, C. Bonatto, S. Ortolani, B. Barbuy
Title: FSR584 – a new globular cluster in the Galaxy?
Comments: Astronomy and Astrophysics, accepted. 6 pages and 6 figures

Abstract: We investigate the nature of the recently catalogued star cluster candidate FSR584, which is projected in the direction of the molecular cloud W3 and may be the nearest globular cluster to the Sun. 2MASS CMDs, the stellar radial density profile, and proper motions are employed to derive fundamental and structural parameters. The CMD morphology and the radial density profile show that FSR584 is an old star cluster. With proper motions, the properties of FSR584 are consistent with a metal-poor globular cluster with a well-defined turnoff and evidence of a blue horizontal-branch. FSR584 might be a Palomar-like halo globular cluster that is moving towards the Galactic plane. The distance from the Sun is approx 1.4kpc, and it is located at approx 1kpc outside the Solar circle. The radial density profile is characterized by a core radius of rc=0.3+/-0.1 pc. However, we cannot exclude the possibility of an old open cluster. Near-infrared photometry coupled to proper motions support the scenario where FSR584 is a new globular cluster in the Galaxy. The absorption is A_V=9.2+/-0.6$, which makes it a limiting object in the optical and explains why it has so far been overlooked

This one is apparently projected over starforming region W3, and at a distance of only 1.4 kpc (4,600 ly). It would probably even beat the recently discovered record holder, FSR 1767. However, as of this time, the authors cannot exclude that this may be an old open cluster.

A preliminary webpage for this probable globular has been created at



2 thoughts on “FSR 584: Another new nearby globular cluster candidate

  1. mcastel

    Many thanks for your post, Hartmut.
    It seems that globular clusters in the Milky Way are much more than once believed.. that’s really intriguing !


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