Email Detail

HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "url": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/C2VTROKWXHRTM4FILIKRDCFXUA22JQHA/",
    "mailinglist": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/",
    "message_id": "[email protected]",
    "message_id_hash": "C2VTROKWXHRTM4FILIKRDCFXUA22JQHA",
    "thread": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/thread/C2VTROKWXHRTM4FILIKRDCFXUA22JQHA/",
    "sender": {
        "address": "K3IO (a) verizon.net",
        "mailman_id": "79a9b3ddaa4b44baae47f92374974ac4",
        "emails": "https://mailman.amsat.org/hyperkitty/api/sender/79a9b3ddaa4b44baae47f92374974ac4/emails/"
    },
    "sender_name": "Tom Clark, K3IO",
    "subject": "[amsat-bb] Re: Since We Are Off Topic Somewhat....",
    "date": "2008-02-15T19:52:05Z",
    "parent": null,
    "children": [
        "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/MA56VECODUBV7CGPR5AKGVJBLKYZ5AXA/"
    ],
    "votes": {
        "likes": 0,
        "dislikes": 0,
        "status": "neutral"
    },
    "content": "Bill Jones asked:\n> While discussing this topic of orbital decay, I wonder if someone would \n> comment on the apparent anomoly whereby a sat in leo that encounters drag \n> actually speeds up (since as it's altitude decreases, the orbital speed \n> increases), and how this might be a factor in the comparison of the heating \n> effects on an object that decays gradually from orbit vs an object like the \n> shuttle that is taken out of orbit by actually reducing it's speed with \n> thrust.   I have my own intuitive theories on this but would like to hear more \n> informed opinions.\n\nWhat confuses people is that the orbital PERIOD (minutes/orbit) \ndecreases with drag, and hence its reciprocal (measured in units like \nlike orbits/day) increases. As the satellite gives up kinetic energy to \nheat, it falls into a lower orbit, where it must move faster. The \nrelation is that the square of the period is proportional to the cube of \nthe size of the orbit.\n\nAll this is is embodied in Kepler's 3rd law (see \nhttp://en.wikipedia.org/wiki/Kepler%27s_laws_of_planetary_motion) which \nthe Wiki states as:\n\n    * \"The squares <http://en.wikipedia.org/wiki/Square_%28algebra%29>\n      of the orbital periods\n      <http://en.wikipedia.org/wiki/Orbital_period> of planets are\n      directly proportional\n      <http://en.wikipedia.org/wiki/Proportionality_%28mathematics%29>\n      to the cubes <http://en.wikipedia.org/wiki/Cube_%28arithmetic%29>\n      of the semi-major axes <http://en.wikipedia.org/wiki/Major_axis>\n      (the \"half-length\" of the ellipse) of their orbits. This means not\n      only that larger orbits have longer periods, but also that the\n      speed of a planet in a larger orbit is lower than in a smaller orbit.\"\n\nAn animated \"movie\" of Kepler's 3rd law can be seen at \nhttp://people.scs.fsu.edu/~dduke/kepler3.html \n<http://people.scs.fsu.edu/%7Edduke/kepler3.html>.\n\n73, Tom\n",
    "attachments": []
}