{
  "abstract": "We present the discovery of the Milky Way satellite Rubin-GC1 (Rubin J1628-1735) using data from the NSF-DOE Vera C. Rubin Observatory's Early Data Preview 2. The system was discovered in the direction of the Galactic bulge with $(l, b) \\sim (359^{\\circ}, 21^{\\circ})$ in a region of high stellar density and a foreground reddening of $E(B-V) \\approx 0.7$. We simultaneously fit the morphology and isochrone parameters of Rubin-GC1, determining that it is a faint ($M_V = -2.4^{+0.5}_{-0.7}$) and compact ($r_{1/2} = 5^{+1}_{-1}$ pc) Milky Way satellite at a distance of $D_\\odot = 31^{+3}_{-3}$ kpc; its stellar population is intermediate-age ($τ=9.2^{+1.2}_{-0.7}$ Gyr) and moderately metal-rich ($\\mathrm{[Fe/H]_{iso}}=-0.73^{+0.04}_{-0.04}$). Together, these properties suggest Rubin-GC1 is most likely a star cluster in the faint tail of the luminosity function of globular clusters surrounding the Milky Way. We identify a distinct proper motion signature from Rubin-GC1 in Gaia DR3, and from a comparison of the system's 5D phase space information to $N$-body models of the Sagittarius dwarf spheroidal galaxy's tidal stream, we determine that Rubin-GC1 is likely an accreted cluster associated with the Sagittarius leading arm. The discovery of Rubin-GC1 highlights the potential of Rubin to uncover faint, resolved satellites in dust-shrouded regions of the Milky Way, including remnants of the accretion events that have shaped the Galaxy's hierarchical assembly.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.15872",
  "author_total": 12,
  "authors": [
    {
      "name": "Aashay Pai"
    },
    {
      "name": "William Cerny"
    },
    {
      "name": "Andrew B. Pace"
    },
    {
      "name": "Alex Drlica-Wagner"
    },
    {
      "name": "Peter S. Ferguson"
    },
    {
      "name": "Marla Geha"
    },
    {
      "name": "Chin Yi Tan"
    },
    {
      "name": "Sasha N. Campana"
    },
    {
      "name": "Burçin Mutlu-Pakdil"
    },
    {
      "name": "Alexander H. Riley"
    },
    {
      "name": "Nora Shipp"
    },
    {
      "name": "Guy S. Stringfellow"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bchgake3t572h.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.15872",
  "fulltext_url": null,
  "id": "bchgake3t572h",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.15872",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.GA"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2609.15872",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-14",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/bchgake3t572h.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:25Z",
      "native_id": "2609.15872",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.15872"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "Rubin Observatory Reveals a Dust-Shrouded Halo Globular Cluster in Ophiuchus",
  "title_text": "Rubin Observatory Reveals a Dust-Shrouded Halo Globular Cluster in Ophiuchus",
  "type": "preprint",
  "updated_at": "2026-10-30T12:21:25Z",
  "url": "https://research.draconitic.com/paper/bchgake3t572h",
  "venue": "arXiv",
  "versions": []
}