{
  "export": {
    "source": "https://urth.darkrealm.vip/thread/urth/640",
    "note": "Exported from an unofficial mirror of a public mailing list. Copyright in each message remains with the person who wrote it.  Email addresses are obscured as `user at host`, the form the original archive published. This file was rebuilt from parsed fields rather than retained headers, so it is faithful in content but not byte-exact.",
    "addresses": "obscured as 'user at host'"
  },
  "archive": "urth",
  "thread": {
    "id": 640,
    "subject": "Borski-mantis Sleuthing",
    "messages": 1,
    "voices": 1,
    "first": "1998-05-20T05:31:00+00:00",
    "last": "1998-05-20T05:31:00+00:00"
  },
  "messages": [
    {
      "message_id": "<urth-v0011-0075@digest.urth.net>",
      "from": {
        "name": "m.driussi",
        "address": "m.driussi at genie.com"
      },
      "date": "1998-05-20T05:31:00+00:00",
      "subject": "(urth) Borski-mantis Sleuthing",
      "in_reply_to": null,
      "reply_link": null,
      "blocks": [
        {
          "kind": "text",
          "depth": 0,
          "text": "Robert Borski,\n\nRe: quote about VRT as 16 local years old, but looking older.  Great!\nOkay, so a 30 hour day might be a tad long, but good enough for the\nmoment.\n\nRe: the \"R\" of VRT, well I'll quip \"Rodman\" but I'm really curious to\nknow.\n\nAnd spill the beans and genes on David's mother!\n\n36 Ophiuchi A and 36 Ophiuchi B (18.2 ly from Earth)\n\n(I like this one for the 3 stars, the twins, and the improbability\nfactor.)\n\n\"This system, consisting of 3 stars, lies almost directly between us\nand the center of our Galaxy.  The orbital elements of the system\nhave not yet been established [in 1964].  The brightest star, 36\nOphiuchi A, is in spectral class K2, has an apparent magnitude of\n5.17, and a mass about 0.77 times that of the Sun.  Thus it has a\nprobability of about 0.023 (or 1 chance in 43) of having a habitable\nplanet.  As for 36 Ophiuchi B, it is in spectral class K1, with a\nmass about 0.76 times that of the Sun.  Its probability of having a\nhabitable planet is 0.020 (or 1 chance in 50).  This pair of stars\nis very close indeed to being an example of `twin suns.'\n\n\"Here, as in the Alpha Centauri system, we might calculate the chance\nof a habitable planet orbiting around either of the two brighter\ncomponents of the system.  This probability comes to 0.042 (1 chance\nin 24).\n\n\"Finally, the third component, 36 Ophiuchi C, in spectral class K6,\nhas a mass about 0.63 times that of our Sun and is another\nboarderline case for which the probability of a habitable planet is\nvery small\" (Dole & Asimov, PLANETS FOR MAN, p. 182).\n\nAnother book, much more recent, sez that the separation for A and B\nis 73.6 AU and period is 548 years: lifezones are\nA and B (.35-.75 AU)\nand \"C\" [here called 664 Ophiuchus] (.25-.53 AU).\n\nAll too low for our numbers.  (Maybe I should try a 27 hour day?)\n\n=mantis="
        }
      ]
    }
  ]
}