A library that computes the ephemerides.
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 

271 line
18 KiB

  1. #!/usr/bin/env python3
  2. # Kosmorrolib - The Library To Compute Your Ephemerides
  3. # Copyright (C) 2021 Jérôme Deuchnord <jerome@deuchnord.fr>
  4. #
  5. # This program is free software: you can redistribute it and/or modify
  6. # it under the terms of the GNU Affero General Public License as
  7. # published by the Free Software Foundation, either version 3 of the
  8. # License, or (at your option) any later version.
  9. #
  10. # This program is distributed in the hope that it will be useful,
  11. # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12. # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13. # GNU Affero General Public License for more details.
  14. #
  15. # You should have received a copy of the GNU Affero General Public License
  16. # along with this program. If not, see <https://www.gnu.org/licenses/>.
  17. from datetime import date, datetime, timedelta
  18. from typing import Union
  19. from skyfield.searchlib import find_discrete, find_maxima
  20. from skyfield.timelib import Time
  21. from skyfield.constants import tau
  22. from skyfield.errors import EphemerisRangeError
  23. from .model import Position, AsterEphemerides, MoonPhase, Object, ASTERS
  24. from .dateutil import translate_to_timezone, normalize_datetime
  25. from .core import get_skf_objects, get_timescale, get_iau2000b
  26. from .enum import MoonPhaseType
  27. from .exceptions import OutOfRangeDateError
  28. RISEN_ANGLE = -0.8333
  29. def _get_skyfield_to_moon_phase(
  30. times: [Time], vals: [int], now: Time, timezone: int
  31. ) -> Union[MoonPhase, None]:
  32. tomorrow = get_timescale().utc(
  33. now.utc_datetime().year, now.utc_datetime().month, now.utc_datetime().day + 1
  34. )
  35. next_phase_time = None
  36. i = 0
  37. # Find the current moon phase:
  38. for i, time in enumerate(times):
  39. if now.utc_datetime() <= time.utc_datetime():
  40. if time.utc_datetime() >= tomorrow.utc_datetime():
  41. i -= 1
  42. break
  43. current_phase = MoonPhaseType(vals[i])
  44. if current_phase in [
  45. MoonPhaseType.NEW_MOON,
  46. MoonPhaseType.FIRST_QUARTER,
  47. MoonPhaseType.FULL_MOON,
  48. MoonPhaseType.LAST_QUARTER,
  49. ]:
  50. current_phase_time = translate_to_timezone(times[i].utc_datetime(), timezone)
  51. else:
  52. current_phase_time = None
  53. # Find the next moon phase
  54. for j in range(i + 1, len(times)):
  55. if vals[j] in [0, 2, 4, 6]:
  56. next_phase_time = translate_to_timezone(times[j].utc_datetime(), timezone)
  57. break
  58. return MoonPhase(current_phase, current_phase_time, next_phase_time)
  59. def get_moon_phase(for_date: date = date.today(), timezone: int = 0) -> MoonPhase:
  60. """Calculate and return the moon phase for the given date, adjusted to the given timezone if any.
  61. Get the moon phase for the 27 March, 2021:
  62. >>> get_moon_phase(date(2021, 3, 27))
  63. <MoonPhase phase_type=MoonPhaseType.WAXING_GIBBOUS time=None next_phase_date=2021-03-28 18:48:10.902298+00:00>
  64. When the moon phase is a new moon, a first quarter, a full moon or a last quarter, you get the exact time
  65. of its happening too:
  66. >>> get_moon_phase(datetime(2021, 3, 28))
  67. <MoonPhase phase_type=MoonPhaseType.FULL_MOON time=2021-03-28 18:48:10.902298+00:00 next_phase_date=2021-04-04 10:02:27.393689+00:00>
  68. Get the moon phase for the 27 March, 2021, in the UTC+2 timezone:
  69. >>> get_moon_phase(date(2021, 3, 27), timezone=2)
  70. <MoonPhase phase_type=MoonPhaseType.WAXING_GIBBOUS time=None next_phase_date=2021-03-28 20:48:10.902298+02:00>
  71. Note that the moon phase can only be computed for a date range.
  72. Asking for the moon phase with an out of range date will result in an exception:
  73. >>> get_moon_phase(date(1000, 1, 1))
  74. Traceback (most recent call last):
  75. ...
  76. kosmorrolib.exceptions.OutOfRangeDateError: The date must be between 1899-08-09 and 2053-09-26
  77. """
  78. earth = get_skf_objects()["earth"]
  79. moon = get_skf_objects()["moon"]
  80. sun = get_skf_objects()["sun"]
  81. def moon_phase_at(time: Time):
  82. time._nutation_angles = get_iau2000b(time)
  83. current_earth = earth.at(time)
  84. _, mlon, _ = current_earth.observe(moon).apparent().ecliptic_latlon("date")
  85. _, slon, _ = current_earth.observe(sun).apparent().ecliptic_latlon("date")
  86. return (((mlon.radians - slon.radians) // (tau / 8)) % 8).astype(int)
  87. moon_phase_at.rough_period = 7.0 # one lunar phase per week
  88. today = get_timescale().utc(for_date.year, for_date.month, for_date.day)
  89. start_time = get_timescale().utc(for_date.year, for_date.month, for_date.day - 10)
  90. end_time = get_timescale().utc(for_date.year, for_date.month, for_date.day + 10)
  91. try:
  92. times, phases = find_discrete(start_time, end_time, moon_phase_at)
  93. return _get_skyfield_to_moon_phase(times, phases, today, timezone)
  94. except EphemerisRangeError as error:
  95. start = translate_to_timezone(error.start_time.utc_datetime(), timezone)
  96. end = translate_to_timezone(error.end_time.utc_datetime(), timezone)
  97. start = date(start.year, start.month, start.day) + timedelta(days=12)
  98. end = date(end.year, end.month, end.day) - timedelta(days=12)
  99. raise OutOfRangeDateError(start, end) from error
  100. def get_ephemerides(
  101. position: Position, for_date: date = date.today(), timezone: int = 0
  102. ) -> [AsterEphemerides]:
  103. """Compute and return the ephemerides for the given position and date, adjusted to the given timezone if any.
  104. Compute the ephemerides for June 9th, 2021:
  105. >>> pos = Position(50.5824, 3.0624)
  106. >>> get_ephemerides(pos, date(2021, 6, 9))
  107. [<AsterEphemerides rise_time=2021-06-09 03:36:00 culmination_time=2021-06-09 11:47:00 set_time=2021-06-09 19:58:00 aster=<Object type=STAR name=SUN />>, <AsterEphemerides rise_time=2021-06-09 02:59:00 culmination_time=2021-06-09 11:02:00 set_time=2021-06-09 19:16:00 aster=<Object type=SATELLITE name=MOON />>, <AsterEphemerides rise_time=2021-06-09 04:06:00 culmination_time=2021-06-09 11:58:00 set_time=2021-06-09 19:49:00 aster=<Object type=PLANET name=MERCURY />>, <AsterEphemerides rise_time=2021-06-09 04:52:00 culmination_time=2021-06-09 13:13:00 set_time=2021-06-09 21:34:00 aster=<Object type=PLANET name=VENUS />>, <AsterEphemerides rise_time=2021-06-09 06:38:00 culmination_time=2021-06-09 14:40:00 set_time=2021-06-09 22:41:00 aster=<Object type=PLANET name=MARS />>, <AsterEphemerides rise_time=2021-06-09 23:43:00 culmination_time=2021-06-09 04:54:00 set_time=2021-06-09 10:01:00 aster=<Object type=PLANET name=JUPITER />>, <AsterEphemerides rise_time=2021-06-09 23:02:00 culmination_time=2021-06-09 03:41:00 set_time=2021-06-09 08:16:00 aster=<Object type=PLANET name=SATURN />>, <AsterEphemerides rise_time=2021-06-09 01:56:00 culmination_time=2021-06-09 09:18:00 set_time=2021-06-09 16:40:00 aster=<Object type=PLANET name=URANUS />>, <AsterEphemerides rise_time=2021-06-09 00:27:00 culmination_time=2021-06-09 06:13:00 set_time=2021-06-09 11:59:00 aster=<Object type=PLANET name=NEPTUNE />>, <AsterEphemerides rise_time=2021-06-09 22:22:00 culmination_time=2021-06-09 02:32:00 set_time=2021-06-09 06:38:00 aster=<Object type=PLANET name=PLUTO />>]
  108. Compute the ephemerides for June 9th, 2021:
  109. >>> get_ephemerides(pos, date(2021, 6, 9), timezone=2)
  110. [<AsterEphemerides rise_time=2021-06-09 05:36:00 culmination_time=2021-06-09 13:47:00 set_time=2021-06-09 21:58:00 aster=<Object type=STAR name=SUN />>, <AsterEphemerides rise_time=2021-06-09 04:59:00 culmination_time=2021-06-09 13:02:00 set_time=2021-06-09 21:16:00 aster=<Object type=SATELLITE name=MOON />>, <AsterEphemerides rise_time=2021-06-09 06:06:00 culmination_time=2021-06-09 13:58:00 set_time=2021-06-09 21:49:00 aster=<Object type=PLANET name=MERCURY />>, <AsterEphemerides rise_time=2021-06-09 06:52:00 culmination_time=2021-06-09 15:13:00 set_time=2021-06-09 23:34:00 aster=<Object type=PLANET name=VENUS />>, <AsterEphemerides rise_time=2021-06-09 08:38:00 culmination_time=2021-06-09 16:40:00 set_time=2021-06-09 00:44:00 aster=<Object type=PLANET name=MARS />>, <AsterEphemerides rise_time=2021-06-09 01:47:00 culmination_time=2021-06-09 06:54:00 set_time=2021-06-09 12:01:00 aster=<Object type=PLANET name=JUPITER />>, <AsterEphemerides rise_time=2021-06-09 01:06:00 culmination_time=2021-06-09 05:41:00 set_time=2021-06-09 10:16:00 aster=<Object type=PLANET name=SATURN />>, <AsterEphemerides rise_time=2021-06-09 03:56:00 culmination_time=2021-06-09 11:18:00 set_time=2021-06-09 18:40:00 aster=<Object type=PLANET name=URANUS />>, <AsterEphemerides rise_time=2021-06-09 02:27:00 culmination_time=2021-06-09 08:13:00 set_time=2021-06-09 13:59:00 aster=<Object type=PLANET name=NEPTUNE />>, <AsterEphemerides rise_time=2021-06-09 00:26:00 culmination_time=2021-06-09 04:32:00 set_time=2021-06-09 08:38:00 aster=<Object type=PLANET name=PLUTO />>]
  111. Objects may not rise or set on the given date (i.e. they rise the previous day or set the next day).
  112. When this happens, you will get `None` values on the rise or set time.
  113. Note that this is timezone-dependent:
  114. >>> get_ephemerides(Position(50.5876, 3.0624), date(2021, 9, 14), timezone=2)[1]
  115. <AsterEphemerides rise_time=2021-09-14 16:46:00 culmination_time=2021-09-14 20:29:00 set_time=None aster=<Object type=SATELLITE name=MOON />>
  116. If an objet does not rise nor set due to your latitude, then both rise and set will be `None`:
  117. >>> north_pole = Position(70, 20)
  118. >>> south_pole = Position(-70, 20)
  119. >>> get_ephemerides(north_pole, date(2021, 6, 20))
  120. [<AsterEphemerides rise_time=None culmination_time=2021-06-20 10:42:00 set_time=None aster=<Object type=STAR name=SUN />>, <AsterEphemerides rise_time=2021-06-20 14:30:00 culmination_time=2021-06-20 18:44:00 set_time=2021-06-20 22:53:00 aster=<Object type=SATELLITE name=MOON />>, <AsterEphemerides rise_time=2021-06-20 22:56:00 culmination_time=2021-06-20 09:47:00 set_time=2021-06-20 20:34:00 aster=<Object type=PLANET name=MERCURY />>, <AsterEphemerides rise_time=None culmination_time=2021-06-20 12:20:00 set_time=None aster=<Object type=PLANET name=VENUS />>, <AsterEphemerides rise_time=None culmination_time=2021-06-20 13:17:00 set_time=None aster=<Object type=PLANET name=MARS />>, <AsterEphemerides rise_time=2021-06-20 23:06:00 culmination_time=2021-06-20 03:04:00 set_time=2021-06-20 06:58:00 aster=<Object type=PLANET name=JUPITER />>, <AsterEphemerides rise_time=2021-06-20 23:28:00 culmination_time=2021-06-20 01:48:00 set_time=2021-06-20 04:05:00 aster=<Object type=PLANET name=SATURN />>, <AsterEphemerides rise_time=2021-06-20 21:53:00 culmination_time=2021-06-20 07:29:00 set_time=2021-06-20 17:02:00 aster=<Object type=PLANET name=URANUS />>, <AsterEphemerides rise_time=2021-06-20 22:51:00 culmination_time=2021-06-20 04:22:00 set_time=2021-06-20 09:50:00 aster=<Object type=PLANET name=NEPTUNE />>, <AsterEphemerides rise_time=None culmination_time=2021-06-20 00:40:00 set_time=None aster=<Object type=PLANET name=PLUTO />>]
  121. >>> get_ephemerides(north_pole, date(2021, 12, 21))
  122. [<AsterEphemerides rise_time=None culmination_time=2021-12-21 10:38:00 set_time=None aster=<Object type=STAR name=SUN />>, <AsterEphemerides rise_time=None culmination_time=2021-12-21 00:04:00 set_time=None aster=<Object type=SATELLITE name=MOON />>, <AsterEphemerides rise_time=None culmination_time=2021-12-21 11:33:00 set_time=None aster=<Object type=PLANET name=MERCURY />>, <AsterEphemerides rise_time=2021-12-21 11:58:00 culmination_time=2021-12-21 12:33:00 set_time=2021-12-21 13:08:00 aster=<Object type=PLANET name=VENUS />>, <AsterEphemerides rise_time=None culmination_time=2021-12-21 08:54:00 set_time=None aster=<Object type=PLANET name=MARS />>, <AsterEphemerides rise_time=2021-12-21 11:07:00 culmination_time=2021-12-21 14:43:00 set_time=2021-12-21 18:19:00 aster=<Object type=PLANET name=JUPITER />>, <AsterEphemerides rise_time=2021-12-21 11:32:00 culmination_time=2021-12-21 13:33:00 set_time=2021-12-21 15:33:00 aster=<Object type=PLANET name=SATURN />>, <AsterEphemerides rise_time=2021-12-21 09:54:00 culmination_time=2021-12-21 19:13:00 set_time=2021-12-21 04:37:00 aster=<Object type=PLANET name=URANUS />>, <AsterEphemerides rise_time=2021-12-21 10:49:00 culmination_time=2021-12-21 16:05:00 set_time=2021-12-21 21:21:00 aster=<Object type=PLANET name=NEPTUNE />>, <AsterEphemerides rise_time=None culmination_time=2021-12-21 12:31:00 set_time=None aster=<Object type=PLANET name=PLUTO />>]
  123. >>> get_ephemerides(south_pole, date(2021, 6, 20))
  124. [<AsterEphemerides rise_time=None culmination_time=2021-06-20 10:42:00 set_time=None aster=<Object type=STAR name=SUN />>, <AsterEphemerides rise_time=2021-06-20 11:10:00 culmination_time=2021-06-20 19:06:00 set_time=2021-06-20 01:20:00 aster=<Object type=SATELLITE name=MOON />>, <AsterEphemerides rise_time=2021-06-20 07:47:00 culmination_time=2021-06-20 09:47:00 set_time=2021-06-20 11:48:00 aster=<Object type=PLANET name=MERCURY />>, <AsterEphemerides rise_time=None culmination_time=2021-06-20 12:20:00 set_time=None aster=<Object type=PLANET name=VENUS />>, <AsterEphemerides rise_time=2021-06-20 12:14:00 culmination_time=2021-06-20 13:17:00 set_time=2021-06-20 14:21:00 aster=<Object type=PLANET name=MARS />>, <AsterEphemerides rise_time=2021-06-20 18:32:00 culmination_time=2021-06-20 03:04:00 set_time=2021-06-20 11:32:00 aster=<Object type=PLANET name=JUPITER />>, <AsterEphemerides rise_time=2021-06-20 15:20:00 culmination_time=2021-06-20 01:48:00 set_time=2021-06-20 12:12:00 aster=<Object type=PLANET name=SATURN />>, <AsterEphemerides rise_time=2021-06-20 04:32:00 culmination_time=2021-06-20 07:29:00 set_time=2021-06-20 10:26:00 aster=<Object type=PLANET name=URANUS />>, <AsterEphemerides rise_time=2021-06-20 21:28:00 culmination_time=2021-06-20 04:22:00 set_time=2021-06-20 11:13:00 aster=<Object type=PLANET name=NEPTUNE />>, <AsterEphemerides rise_time=None culmination_time=2021-06-20 00:40:00 set_time=None aster=<Object type=PLANET name=PLUTO />>]
  125. >>> get_ephemerides(south_pole, date(2021, 12, 22))
  126. [<AsterEphemerides rise_time=None culmination_time=2021-12-22 10:39:00 set_time=None aster=<Object type=STAR name=SUN />>, <AsterEphemerides rise_time=None culmination_time=2021-12-22 01:01:00 set_time=None aster=<Object type=SATELLITE name=MOON />>, <AsterEphemerides rise_time=None culmination_time=2021-12-22 11:35:00 set_time=None aster=<Object type=PLANET name=MERCURY />>, <AsterEphemerides rise_time=None culmination_time=2021-12-22 12:27:00 set_time=None aster=<Object type=PLANET name=VENUS />>, <AsterEphemerides rise_time=None culmination_time=2021-12-22 08:53:00 set_time=None aster=<Object type=PLANET name=MARS />>, <AsterEphemerides rise_time=2021-12-22 05:52:00 culmination_time=2021-12-22 14:40:00 set_time=2021-12-22 23:26:00 aster=<Object type=PLANET name=JUPITER />>, <AsterEphemerides rise_time=2021-12-22 02:41:00 culmination_time=2021-12-22 13:29:00 set_time=2021-12-22 00:21:00 aster=<Object type=PLANET name=SATURN />>, <AsterEphemerides rise_time=2021-12-22 16:01:00 culmination_time=2021-12-22 19:09:00 set_time=2021-12-22 22:17:00 aster=<Object type=PLANET name=URANUS />>, <AsterEphemerides rise_time=2021-12-22 08:59:00 culmination_time=2021-12-22 16:01:00 set_time=2021-12-22 23:04:00 aster=<Object type=PLANET name=NEPTUNE />>, <AsterEphemerides rise_time=None culmination_time=2021-12-22 12:27:00 set_time=None aster=<Object type=PLANET name=PLUTO />>]
  127. Note that the ephemerides can only be computed for a date range.
  128. Asking for the ephemerides with an out of range date will result in an exception:
  129. >>> get_ephemerides(pos, date(1000, 1, 1))
  130. Traceback (most recent call last):
  131. ...
  132. kosmorrolib.exceptions.OutOfRangeDateError: The date must be between 1899-07-29 and 2053-10-07
  133. """
  134. ephemerides = []
  135. def get_angle(for_aster: Object):
  136. def fun(time: Time) -> float:
  137. return (
  138. position.get_planet_topos()
  139. .at(time)
  140. .observe(for_aster.skyfield_object)
  141. .apparent()
  142. .altaz()[0]
  143. .degrees
  144. )
  145. fun.rough_period = 1.0
  146. return fun
  147. def is_risen(for_aster: Object):
  148. def fun(time: Time) -> bool:
  149. return get_angle(for_aster)(time) > RISEN_ANGLE
  150. fun.rough_period = 0.5
  151. return fun
  152. start_time = get_timescale().utc(
  153. for_date.year, for_date.month, for_date.day, -timezone
  154. )
  155. end_time = get_timescale().utc(
  156. for_date.year, for_date.month, for_date.day, 23 - timezone, 59, 59
  157. )
  158. try:
  159. for aster in ASTERS:
  160. rise_times, arr = find_discrete(start_time, end_time, is_risen(aster))
  161. culmination_time, _ = find_maxima(
  162. start_time,
  163. end_time,
  164. f=get_angle(aster),
  165. epsilon=1.0 / 3600 / 24,
  166. num=12,
  167. )
  168. if len(culmination_time) == 1:
  169. culmination_time = culmination_time[0]
  170. else:
  171. culmination_time = None
  172. rise_time, set_time = None, None
  173. if len(rise_times) == 2:
  174. rise_time = rise_times[0 if arr[0] else 1]
  175. set_time = rise_times[1 if not arr[1] else 0]
  176. elif len(rise_times) == 1:
  177. rise_time = rise_times[0] if arr[0] else None
  178. set_time = rise_times[0] if not arr[0] else None
  179. # Convert the Time instances to Python datetime objects
  180. if rise_time is not None:
  181. rise_time = normalize_datetime(
  182. translate_to_timezone(
  183. rise_time.utc_datetime().replace(microsecond=0), to_tz=timezone
  184. )
  185. )
  186. if culmination_time is not None:
  187. culmination_time = normalize_datetime(
  188. translate_to_timezone(
  189. culmination_time.utc_datetime().replace(microsecond=0),
  190. to_tz=timezone,
  191. )
  192. )
  193. if set_time is not None:
  194. set_time = normalize_datetime(
  195. translate_to_timezone(
  196. set_time.utc_datetime().replace(microsecond=0), to_tz=timezone
  197. )
  198. )
  199. ephemerides.append(
  200. AsterEphemerides(rise_time, culmination_time, set_time, aster=aster)
  201. )
  202. except EphemerisRangeError as error:
  203. start = translate_to_timezone(error.start_time.utc_datetime(), timezone)
  204. end = translate_to_timezone(error.end_time.utc_datetime(), timezone)
  205. start = date(start.year, start.month, start.day + 1)
  206. end = date(end.year, end.month, end.day - 1)
  207. raise OutOfRangeDateError(start, end) from error
  208. return ephemerides