{
  "abstract": "We report the bow shock disappearing (BSD) events at Mercury under quiet solar wind conditions. Using data from the MESSENGER spacecraft, we identified eight BSD events. Assuming a representative solar wind velocity of 400 km s ⁻¹ , we calculated the critical solar wind densities required for the Alfvén Mach number to equal unity, at which point a bow shock cannot form. In all eight events, these critical densities were substantially lower than the typical solar wind densities at Mercury’s heliocentric distance. The resulting extremely low densities produced high Alfvén speeds, driving the solar wind Alfvén Mach number below unity and causing the bow shock to disappear. BSD events are rare and occur in markedly different space environments at Mercury, warranting detailed further investigation through multipoint observations by the BepiColombo mission.",
  "abstract_shown": true,
  "affiliations": [
    "Macau University of Science and Technology",
    "CNSA Macau Center for Space Exploration and Science",
    "Shandong Institute of Advanced Technology (SDIAT)"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Peishan He",
      "orcid": "0000-0002-6721-0497"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Xiaojun Xu",
      "orcid": "0000-0002-2309-0649"
    },
    {
      "affs": [
        2
      ],
      "name": "Qing Chang",
      "orcid": "0000-0003-4883-949X"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/53975g1eyzsv7.bib",
  "cited_by": 0,
  "doi": "10.3847/1538-3881/aea988",
  "fulltext_url": null,
  "id": "53975g1eyzsv7",
  "issns": [
    "0004-6256",
    "1538-3881"
  ],
  "landing_url": "https://iopscience.iop.org/article/10.3847/1538-3881/aea988",
  "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",
      "3103|Ionosphere and magnetosphere dynamics"
    ]
  ],
  "openalex": "W7222593370",
  "pdf_url": "https://iopscience.iop.org/article/10.3847/1538-3881/aea988/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-16",
  "publisher": "American Astronomical Society",
  "ris": "https://research.draconitic.com/paper/53975g1eyzsv7.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:14Z",
      "native_id": "10.3847/1538-3881/aea988",
      "source": "crossref",
      "url": "https://iopscience.iop.org/article/10.3847/1538-3881/aea988"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "journal-openalex:3103|Stellar, planetary, and galactic studies",
      "subfield": "stellar"
    }
  ],
  "title": "Observations of Mercury’s Bow Shock Disappearance in Quiet Solar Wind",
  "title_text": "Observations of Mercury’s Bow Shock Disappearance in Quiet Solar Wind",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:18:14Z",
  "url": "https://research.draconitic.com/paper/53975g1eyzsv7",
  "venue": "The Astronomical Journal",
  "versions": []
}