{
  "id": "1612.00834",
  "version": "v1",
  "published": "2016-12-02T20:51:53.000Z",
  "updated": "2016-12-02T20:51:53.000Z",
  "title": "Gaia Shows That Messier 40 is Definitely Not a Binary Star",
  "authors": [
    "Michael R. Merrifield",
    "Meghan E. Gray",
    "Brady Haran"
  ],
  "comment": "1 page. Refereed and accepted for publication in Observatory",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "M40 has always been something of an oddity in the Messier Catalogue, since it is just a pair of stars rather than an extended object. Doubts have also been expressed as to whether it is even a physical binary. Here, we note that the Hipparcos/Gaia parallaxes for these two stars remove all doubt: Messier 40 comprises a pair of entirely unrelated stars.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2016-12-02T20:51:53.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "binary star",
      "messier catalogue",
      "hipparcos/gaia parallaxes",
      "stars remove",
      "extended object"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 1,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}