{
  "abstract": "We present new constraints on a candidate third companion in the 61 Cygni binary system-one of the closest neighbors to our solar system (3.5 pc), the first stars to have a measured parallax, and two of the most favorable targets for habitable zone exo-Earth searches with future direct imaging missions. Kervella et al. (2022) first identified the candidate based on a 4.4$σ$ tangential velocity anomaly in the system determined using Hipparcos and Gaia DR3 astrometry of the A and B components. We combine this astrometric evidence with constraints from Gaia DR3 RUWE, MMT/Clio Lp imaging, nearly four decades of radial velocity (RV) measurements (including $\\sim$2 years of new NEID RVs presented here), and N-body dynamical stability calculations of both stars in a Monte Carlo framework to estimate the candidate companion's mass and semi-major axis. Our analysis reveals that all of the available data are compatible with an $\\approx(8 \\pm 3)\\;M_{\\rm Jup}$ super-Jupiter in an $\\approx(8 \\pm 3)$ au orbit, with a broad range of allowed eccentricities and mutual inclinations. Using the Sonora Flame Skimmer evolutionary models, given the system's mature age of $(6.0 \\pm 1.0)$ Gyr, we estimate a companion effective temperature of $(282 \\pm 55)$ K and radius of $(1.02 \\pm 0.02)\\;R_{\\rm Jup}$. Finally, we evaluate the stability of terrestrial planets in the habitable zone (HZ) of 61 Cygni AB in the presence of the giant planet candidate using N-body simulations. A companion semi-major axis $\\lesssim$5 au, irrespective of the planet-planet mutual inclination, and between $\\approx$5 au and 10 au, for misaligned orbits ($40^o \\lesssim i_{\\rm mut} \\lesssim 140^o$), severely disrupts the HZ. Our results highlight the need to confirm the planet candidate and characterize its orbit to inform future exo-Earth searches with missions such as SHERA, HWO, and LIFE.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.32893",
  "author_total": 19,
  "authors": [
    {
      "name": "Aniket Sanghi"
    },
    {
      "name": "Billy Quarles"
    },
    {
      "name": "Andrea S. J. Lin"
    },
    {
      "name": "Cheyanne Shariat"
    },
    {
      "name": "Pierre Kervella"
    },
    {
      "name": "James Mang"
    },
    {
      "name": "Dimitri Mawet"
    },
    {
      "name": "Mark R. Giovinazzi"
    },
    {
      "name": "Arvind F. Gupta"
    },
    {
      "name": "Charles Beichman"
    },
    {
      "name": "Bertrand Mennesson"
    },
    {
      "name": "Mathilde Mâlin"
    },
    {
      "name": "Jerry W. Xuan"
    },
    {
      "name": "Liton Majumdar"
    },
    {
      "name": "Jack J. Lissauer"
    },
    {
      "name": "Mark Wyatt"
    },
    {
      "name": "William O. Balmer"
    },
    {
      "name": "Eduardo Bendek"
    },
    {
      "name": "Kevin Wagner"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/9wz1k0b0efyc5.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.32893",
  "fulltext_url": null,
  "id": "9wz1k0b0efyc5",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.32893",
  "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.EP"
    ],
    [
      "arxiv",
      "astro-ph.SR"
    ],
    [
      "openalex",
      "3103|Stellar, planetary, and galactic studies"
    ]
  ],
  "openalex": "W7214700282",
  "pdf_url": "https://arxiv.org/pdf/2609.32893",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-26",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/9wz1k0b0efyc5.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:12Z",
      "native_id": "2609.32893",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.32893"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.EP",
      "subfield": "planetary"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.SR",
      "subfield": "stellar"
    }
  ],
  "title": "Worlds Next Door. V. A Candidate Solar System Scale Super-Jupiter in the 61 Cygni Binary System",
  "title_text": "Worlds Next Door. V. A Candidate Solar System Scale Super-Jupiter in the 61 Cygni Binary System",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:12Z",
  "url": "https://research.draconitic.com/paper/9wz1k0b0efyc5",
  "venue": "arXiv",
  "versions": []
}