{
  "abstract": "We report the discovery of two planets, a hot Jupiter (HJ) and a nearby outer sub-Neptune, orbiting the star TOI-4468. This system is unique among the current exoplanet census in that it features a close outer companion to a HJ without an accompanying inner companion. By jointly fitting radial velocity (RV) measurements taken with the NEID spectrograph and transit photometry from the Transiting Exoplanet Survey Satellite (TESS) and several ground-based observatories, we constrain the orbital periods, masses, and radii of these two planets. We confirm the planetary nature of the HJ TOI-4468 b ( R = 1.01 R J , m = 0.54 M J , P = 2.77 days). We also validate the outer planet TOI-4468 c ( R = 0.28 R J , P = 7.01 days) statistically, incorporating constraints from ground-based observations. We also identify, but cannot confirm, an additional RV signal that may be due to an outer giant in this system with an orbital period of 624 days. From the observed geometry of this system, we argue that it must never have encountered an early secular resonance that is thought to excite the mutual inclination of other HJ/outer companion systems. We discuss the possibility of an undetected inner companion, as well as potential implications for HJ formation.",
  "abstract_shown": true,
  "affiliations": [
    "University of Wisconsin–Madison",
    "NASA Goddard Space Flight Center",
    "Center for Astrophysics ∣ Harvard & Smithsonian",
    "Michigan State University",
    "University of Amsterdam",
    "Netherlands Institute for Radio Astronomy",
    "University of Southern Queensland",
    "Astrophysics & Space Institute",
    "Lomonosov Moscow State University",
    "Madison West High School",
    "Instituto de Astrofísica de Canarias (IAC)",
    "Université de Liège",
    "Massachusetts Institute of Technology",
    "Frustaglia Private Observatory",
    "Silesian University of Technology Observatory",
    "Lund University",
    "Universidad de La Laguna (ULL)",
    "Privat Observatory Herges-Hallenberg",
    "Vanderbilt University",
    "California State University, Los Angeles",
    "California Institute of Technology",
    "Stanford University",
    "Princeton University"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 31,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Joseph R. Livesey",
      "orcid": "0000-0003-3888-3753"
    },
    {
      "affs": [
        1
      ],
      "name": "Benjamin J. Hord",
      "orcid": "0000-0001-5084-4269"
    },
    {
      "affs": [
        0
      ],
      "name": "Juliette Becker",
      "orcid": "0000-0002-7733-4522"
    },
    {
      "affs": [
        2
      ],
      "name": "Andrew Vanderburg",
      "orcid": "0000-0001-7246-5438"
    },
    {
      "affs": [
        3
      ],
      "name": "Joseph E. Rodriguez",
      "orcid": "0000-0001-8812-0565"
    },
    {
      "affs": [
        4,
        5
      ],
      "name": "Elise Koo",
      "orcid": "0009-0007-0740-0954"
    },
    {
      "affs": [
        6
      ],
      "name": "Chelsea X. Huang",
      "orcid": "0000-0003-0918-7484"
    },
    {
      "affs": [
        4,
        7
      ],
      "name": "Guðmundur Stefánsson",
      "orcid": "0000-0001-7409-5688"
    },
    {
      "affs": [
        2
      ],
      "name": "Karen A. Collins",
      "orcid": "0000-0001-6588-9574"
    },
    {
      "affs": [
        8
      ],
      "name": "Ivan A. Strakhov",
      "orcid": "0000-0003-0647-6133"
    },
    {
      "affs": [
        9
      ],
      "name": "Zijun He",
      "orcid": "0009-0009-6918-3259"
    },
    {
      "affs": [
        0
      ],
      "name": "Maxwell A. Kroft",
      "orcid": "0009-0002-2757-4138"
    },
    {
      "affs": [
        0
      ],
      "name": "Robert Aloisi",
      "orcid": "0000-0003-2822-616X"
    },
    {
      "affs": [
        10,
        11,
        12
      ],
      "name": "Khalid Barkaoui",
      "orcid": "0000-0003-1464-9276"
    },
    {
      "affs": [
        13
      ],
      "name": "Fabian Rodriguez Frustaglia"
    },
    {
      "affs": [
        0
      ],
      "name": "Alyssa Jankowski",
      "orcid": "0000-0003-4287-004X"
    },
    {
      "affs": [
        14
      ],
      "name": "Kinga Kasprzyk"
    },
    {
      "affs": [
        15
      ],
      "name": "Judith Korth",
      "orcid": "0000-0002-0076-6239"
    },
    {
      "affs": [
        0
      ],
      "name": "Coleman Nelson",
      "orcid": "0009-0009-2277-799X"
    },
    {
      "affs": [
        10,
        16
      ],
      "name": "Hannu Parviainen",
      "orcid": "0000-0001-5519-1391"
    },
    {
      "affs": [
        14
      ],
      "name": "Adam Popowicz",
      "orcid": "0000-0003-3184-5228"
    },
    {
      "affs": [
        17
      ],
      "name": "Manfred Raetz",
      "orcid": "0000-0002-2190-3319"
    },
    {
      "affs": [
        2
      ],
      "name": "Richard P. Schwarz",
      "orcid": "0000-0001-8227-1020"
    },
    {
      "affs": [
        0
      ],
      "name": "Eva Stafne",
      "orcid": "0009-0001-2913-792X"
    },
    {
      "affs": [
        18
      ],
      "name": "Keivan G. Stassun",
      "orcid": "0000-0002-3481-9052"
    },
    {
      "affs": [
        0
      ],
      "name": "Thomas G. Beatty",
      "orcid": "0000-0002-9539-4203"
    },
    {
      "affs": [
        19
      ],
      "name": "Paul Foster"
    },
    {
      "affs": [
        20,
        21
      ],
      "name": "Thomas MacLean",
      "orcid": "0009-0001-6894-2657"
    },
    {
      "affs": [
        0
      ],
      "name": "Devansh Mathur",
      "orcid": "0009-0009-0948-8819"
    },
    {
      "affs": [
        0,
        22
      ],
      "name": "Lizhou Sha",
      "orcid": "0000-0001-5401-8079"
    },
    {
      "affs": [
        0
      ],
      "name": "Melinda Soares-Furtado",
      "orcid": "0000-0001-7493-7419"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/3ysba08n7hxpe.bib",
  "cited_by": 0,
  "doi": "10.3847/1538-3881/aeaee4",
  "fulltext_url": null,
  "id": "3ysba08n7hxpe",
  "issns": [
    "0004-6256",
    "1538-3881"
  ],
  "landing_url": "https://iopscience.iop.org/article/10.3847/1538-3881/aeaee4",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [],
  "openalex": null,
  "pdf_url": "https://iopscience.iop.org/article/10.3847/1538-3881/aeaee4/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-29",
  "publisher": "American Astronomical Society",
  "ris": "https://research.draconitic.com/paper/3ysba08n7hxpe.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:14Z",
      "native_id": "10.3847/1538-3881/aeaee4",
      "source": "crossref",
      "url": "https://iopscience.iop.org/article/10.3847/1538-3881/aeaee4"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "journal-openalex:3103|Stellar, planetary, and galactic studies",
      "subfield": "stellar"
    }
  ],
  "title": "Discovery and Characterization of the TOI-4468 Planetary System: A Transiting Hot Jupiter with a Lone Nearby Outer Companion",
  "title_text": "Discovery and Characterization of the TOI-4468 Planetary System: A Transiting Hot Jupiter with a Lone Nearby Outer Companion",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T00:20:43Z",
  "url": "https://research.draconitic.com/paper/3ysba08n7hxpe",
  "venue": "The Astronomical Journal",
  "versions": []
}