{
 "what": "The red-and-black word mark of an eighteenth-century Ethiopian prayer book, ten marks measured on two photographs, and the noon Sun carried forward from Prague in 1420 to Ethiopia in the 1700s.",
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 "summary": {
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   184.48,
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  "turn_mean": 8.715,
  "turn_sd": 4.219013181091311,
  "turn_mean_error": 1.334169113052098,
  "turn_against_line_mean": 8.238000000000001,
  "line_of_writing_mean": 0.4749999999999999,
  "across_axis_mean": 6.7170000000000005,
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 "stars": [
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  288.43
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 "flower": [
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  282.4
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 "viewpoint": {
  "prague_1420": {
   "latitude": 50.0875,
   "obliquity": 23.514553324958502,
   "june_noon_zenith_distance": 26.572946675041496,
   "45_less": 18.427053324958504
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  "forward": [
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    "year": 1700,
    "precession_deg": 3.9114444444444443,
    "days": 3.9683908531876875,
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   {
    "year": 1750,
    "precession_deg": 4.609916666666667,
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   {
    "year": 1799,
    "precession_deg": 5.294419444444444,
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  ],
  "places": [
   {
    "place": "Gondar, the royal seat 1636-1855",
    "lat": 12.61,
    "June solstice": {
     "z": -10.861734227235178,
     "alt": 79.13826577276483,
     "45-z": 34.138265772764825,
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    "equinox": {
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    "December solstice": {
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    "day_long": 12.743271344157032,
    "day_short": 11.256728655842968
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   {
    "place": "Lake Tana, Bahir Dar",
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    "June solstice": {
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     "alt": 78.11826577276483,
     "45-z": 33.11826577276482,
     "shadow": 0.21040011973957506
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    "equinox": {
     "z": 11.59,
     "alt": 78.41,
     "45-z": 33.41,
     "shadow": 0.20508863975955874
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    "December solstice": {
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    "rise_dec": 113.99060103009052,
    "day_long": 12.68123102959136,
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   {
    "place": "Lalibela",
    "lat": 12.03,
    "June solstice": {
     "z": -11.441734227235179,
     "alt": 78.55826577276483,
     "45-z": 33.55826577276482,
     "shadow": 0.20239349494452075
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    "equinox": {
     "z": 12.03,
     "alt": 77.97,
     "45-z": 32.97,
     "shadow": 0.21310387775435255
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    "December solstice": {
     "z": 35.501734227235175,
     "alt": 54.498265772764825,
     "45-z": 9.498265772764825,
     "shadow": 0.7133387368105756
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    "rise_june": 65.96841596944257,
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    "day_long": 12.707929800275773,
    "day_short": 11.292070199724225
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   {
    "place": "Aksum",
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    "June solstice": {
     "z": -9.341734227235177,
     "alt": 80.65826577276482,
     "45-z": 35.65826577276482,
     "shadow": 0.16450430197399254
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    "equinox": {
     "z": 14.13,
     "alt": 75.87,
     "45-z": 30.869999999999997,
     "shadow": 0.25173934579269674
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    "December solstice": {
     "z": 37.60173422723518,
     "alt": 52.39826577276482,
     "45-z": 7.398265772764823,
     "shadow": 0.770151892150076
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    "rise_june": 65.74971943518237,
    "rise_dec": 114.25028056481763,
    "day_long": 12.836752287552581,
    "day_short": 11.163247712447419
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   {
    "place": "Debre Libanos",
    "lat": 9.71,
    "June solstice": {
     "z": -13.761734227235177,
     "alt": 76.23826577276482,
     "45-z": 31.238265772764823,
     "shadow": 0.24491551794179683
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    "equinox": {
     "z": 9.71,
     "alt": 80.28999999999999,
     "45-z": 35.29,
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    "December solstice": {
     "z": 33.18173422723518,
     "alt": 56.81826577276482,
     "45-z": 11.818265772764818,
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    "rise_dec": 113.83383358723387,
    "day_long": 12.568145962770561,
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  ],
  "overhead": [
   "1750-04-24",
   "1750-08-20"
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  "inverse": {
   "turn as seen": {
    "June solstice, Sun south of the zenith": 59.76173422723518,
    "June solstice, Sun north of the zenith (southern)": -12.818265772764821,
    "equinox": 36.29,
    "December solstice": 12.818265772764821
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   "turn against the line": {
    "June solstice, Sun south of the zenith": 60.23173422723518,
    "June solstice, Sun north of the zenith (southern)": -13.28826577276482,
    "equinox": 36.76,
    "December solstice": 13.28826577276482
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  },
  "ephemeris": {
   "March equinox": {
    "gregorian": "1750-03-20",
    "julian": "1750-03-09",
    "max_alt": 77.26495338249296
   },
   "June solstice": {
    "gregorian": "1750-06-21",
    "julian": "1750-06-10",
    "max_alt": 79.13811416483978
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   "September equinox": {
    "gregorian": "1750-09-23",
    "julian": "1750-09-12",
    "max_alt": 77.31523843199639
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   "December solstice": {
    "gregorian": "1750-12-21",
    "julian": "1750-12-10",
    "max_alt": 53.91808041570536
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  }
 }
}