Merge pull request #122 from Kosmorro/issue72-moon-apogee-perigee

Add support for moon apogee and perigee

.github/workflows/e2e.yml

@@ -16,6 +16,7 @@ jobs:
 
     - name: Prepare tests
       run: |
+        sudo apt update
         sudo apt install ruby
         sudo gem install ronn
         pip install -U setuptools pip requests wheel Babel

kosmorrolib/data.py

@@ -44,7 +44,9 @@ EVENTS = {
     'OPPOSITION': {'message': _('%s is in opposition')},
     'CONJUNCTION': {'message': _('%s and %s are in conjunction')},
     'OCCULTATION': {'message': _('%s occults %s')},
-    'MAXIMAL_ELONGATION': {'message': _("%s's largest elongation")}
+    'MAXIMAL_ELONGATION': {'message': _("%s's largest elongation")},
+    'MOON_PERIGEE': {'message': _("%s is at its perigee")},
+    'MOON_APOGEE': {'message': _("%s is at its apogee")},
 }
 
 
@@ -115,6 +117,9 @@ class Object(Serializable):
         self.skyfield_name = skyfield_name
         self.radius = radius
 
+    def __repr__(self):
+        return '<Object type=%s name=%s />' % (self.get_type(), self.name)
+
     def get_skyfield_object(self) -> SkfPlanet:
         return get_skf_objects()[self.skyfield_name]
 
@@ -176,6 +181,13 @@ class Event(Serializable):
         self.end_time = end_time
         self.details = details
 
+    def __repr__(self):
+        return '<Event type=%s objects=[%s] start=%s end=%s details=%s>' % (self.event_type,
+                                                                            self.objects,
+                                                                            self.start_time,
+                                                                            self.end_time,
+                                                                            self.details)
+
     def get_description(self, show_details: bool = True) -> str:
         description = EVENTS[self.event_type]['message'] % self._get_objects_name()
         if show_details and self.details is not None:

kosmorrolib/events.py

@@ -20,7 +20,7 @@ from datetime import date as date_type
 
 from skyfield.errors import EphemerisRangeError
 from skyfield.timelib import Time
-from skyfield.searchlib import find_discrete, find_maxima
+from skyfield.searchlib import find_discrete, find_maxima, find_minima
 from numpy import pi
 
 from .data import Event, Star, Planet, ASTERS
@@ -135,6 +135,45 @@ def _search_maximal_elongations(start_time: Time, end_time: Time, timezone: int)
     return events
 
 
+def _get_moon_distance():
+    earth = get_skf_objects()['earth']
+    moon = get_skf_objects()['moon']
+
+    def get_distance(time: Time):
+        earth_pos = earth.at(time)
+        moon_pos = earth_pos.observe(moon).apparent()
+
+        return moon_pos.distance().au
+
+    get_distance.rough_period = 1.0
+
+    return get_distance
+
+
+def _search_moon_apogee(start_time: Time, end_time: Time, timezone: int) -> [Event]:
+    moon = ASTERS[1]
+    events = []
+
+    times, _ = find_maxima(start_time, end_time, f=_get_moon_distance(), epsilon=1./24/60)
+
+    for time in times:
+        events.append(Event('MOON_APOGEE', [moon], translate_to_timezone(time.utc_datetime(), timezone)))
+
+    return events
+
+
+def _search_moon_perigee(start_time: Time, end_time: Time, timezone: int) -> [Event]:
+    moon = ASTERS[1]
+    events = []
+
+    times, _ = find_minima(start_time, end_time, f=_get_moon_distance(), epsilon=1./24/60)
+
+    for time in times:
+        events.append(Event('MOON_PERIGEE', [moon], translate_to_timezone(time.utc_datetime(), timezone)))
+
+    return events
+
+
 def search_events(date: date_type, timezone: int = 0) -> [Event]:
     start_time = get_timescale().utc(date.year, date.month, date.day, -timezone)
     end_time = get_timescale().utc(date.year, date.month, date.day + 1, -timezone)
@@ -143,7 +182,9 @@ def search_events(date: date_type, timezone: int = 0) -> [Event]:
         return sorted(flatten_list([
             _search_oppositions(start_time, end_time, timezone),
             _search_conjunction(start_time, end_time, timezone),
-            _search_maximal_elongations(start_time, end_time, timezone)
+            _search_maximal_elongations(start_time, end_time, timezone),
+            _search_moon_apogee(start_time, end_time, timezone),
+            _search_moon_perigee(start_time, end_time, timezone),
         ]), key=lambda event: event.start_time)
     except EphemerisRangeError as error:
         start_date = translate_to_timezone(error.start_time.utc_datetime(), timezone)

kosmorrolib/locales/messages.pot

@@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: kosmorro 0.8.1\n"
 "Report-Msgid-Bugs-To: EMAIL@ADDRESS\n"
-"POT-Creation-Date: 2020-06-07 11:13+0200\n"
+"POT-Creation-Date: 2020-12-01 12:01+0100\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -83,43 +83,53 @@ msgstr ""
 msgid "%s's largest elongation"
 msgstr ""
 
-#: kosmorrolib/data.py:262
+#: kosmorrolib/data.py:48
+#, python-format
+msgid "%s is at its perigee"
+msgstr ""
+
+#: kosmorrolib/data.py:49
+#, python-format
+msgid "%s is at its apogee"
+msgstr ""
+
+#: kosmorrolib/data.py:274
 msgid "Sun"
 msgstr ""
 
-#: kosmorrolib/data.py:263
+#: kosmorrolib/data.py:275
 msgid "Moon"
 msgstr ""
 
-#: kosmorrolib/data.py:264
+#: kosmorrolib/data.py:276
 msgid "Mercury"
 msgstr ""
 
-#: kosmorrolib/data.py:265
+#: kosmorrolib/data.py:277
 msgid "Venus"
 msgstr ""
 
-#: kosmorrolib/data.py:266
+#: kosmorrolib/data.py:278
 msgid "Mars"
 msgstr ""
 
-#: kosmorrolib/data.py:267
+#: kosmorrolib/data.py:279
 msgid "Jupiter"
 msgstr ""
 
-#: kosmorrolib/data.py:268
+#: kosmorrolib/data.py:280
 msgid "Saturn"
 msgstr ""
 
-#: kosmorrolib/data.py:269
+#: kosmorrolib/data.py:281
 msgid "Uranus"
 msgstr ""
 
-#: kosmorrolib/data.py:270
+#: kosmorrolib/data.py:282
 msgid "Neptune"
 msgstr ""
 
-#: kosmorrolib/data.py:271
+#: kosmorrolib/data.py:283
 msgid "Pluto"
 msgstr ""
 

manpage/kosmorro.7.md

@@ -7,6 +7,10 @@ The terms are given in an alphabetically order.
 
 ## TERMS
 
+### Apogee
+
+The Moon is told being at its apogee when it is at its furthest point from the Earth.
+
 ### Conjunction
 
 From the point of view of the Earth, two asters are said in conjunction when they are close together.
@@ -27,6 +31,10 @@ An aster is said in opposition when it is positionned at the exact opposite of t
 For all the superior planets, it is the best moment to observe them, because they will be at the smallest distance to the Earth. Plus, they will appear full.  
 For instance, Mars is in opposition when the angle Mars-Earth-Sun is equal to 180 degrees.
 
+### Perigee
+
+The Moon is told being at its apogee when it is at its nearest point from the Earth.
+
 ### Planet
 
 A planet is an aster that orbits around a star, is not a star itself, is massive enough to maintain it nearly round, and has cleaned its orbit from other massive objects.

test/events.py

@@ -1,6 +1,7 @@
 import unittest
 
 from datetime import date, datetime
+from json import dumps
 
 from kosmorrolib import events
 from kosmorrolib.data import Event, ASTERS
@@ -27,29 +28,38 @@ class EventTestCase(unittest.TestCase):
 
         (date(2025, 1, 16), [Event('OPPOSITION', [ASTERS[4]], datetime(2025, 1, 16, 2, 38))]),
 
-        (date(2027, 2, 19), [Event('OPPOSITION', [ASTERS[4]], datetime(2027, 2, 19, 15, 50))]),
+        (date(2027, 2, 19), [Event('MOON_PERIGEE', [ASTERS[1]], datetime(2027, 2, 19, 7, 38)),
+                             Event('OPPOSITION', [ASTERS[4]], datetime(2027, 2, 19, 15, 50))]),
 
-        (date(2020, 1, 2), [Event('CONJUNCTION', [ASTERS[2], ASTERS[5]], datetime(2020, 1, 2, 16, 41))]),
+        (date(2020, 1, 2), [Event('MOON_APOGEE', [ASTERS[1]], datetime(2020, 1, 2, 1, 32)),
+                            Event('CONJUNCTION', [ASTERS[2], ASTERS[5]], datetime(2020, 1, 2, 16, 41))]),
 
         (date(2020, 1, 12), [Event('CONJUNCTION', [ASTERS[2], ASTERS[6]], datetime(2020, 1, 12, 9, 51)),
                              Event('CONJUNCTION', [ASTERS[2], ASTERS[9]], datetime(2020, 1, 12, 10, 13)),
                              Event('CONJUNCTION', [ASTERS[6], ASTERS[9]], datetime(2020, 1, 12, 16, 57))]),
 
-        (date(2020, 2, 10), [Event('MAXIMAL_ELONGATION', [ASTERS[2]], datetime(2020, 2, 10, 13, 46), details='18.2°')]),
+        (date(2020, 2, 10), [Event('MAXIMAL_ELONGATION', [ASTERS[2]], datetime(2020, 2, 10, 13, 46), details='18.2°'),
+                             Event('MOON_PERIGEE', [ASTERS[1]], datetime(2020, 2, 10, 20, 34))]),
 
         (date(2020, 3, 24), [Event('MAXIMAL_ELONGATION', [ASTERS[2]], datetime(2020, 3, 24, 1, 56), details='27.8°'),
+                             Event('MOON_APOGEE', [ASTERS[1]], datetime(2020, 3, 24, 15, 39)),
                              Event('MAXIMAL_ELONGATION', [ASTERS[3]], datetime(2020, 3, 24, 21, 58), details='46.1°')]),
 
-        (date(2005, 6, 16), [Event('OCCULTATION', [ASTERS[1], ASTERS[5]], datetime(2005, 6, 16, 6, 31))])
+        (date(2005, 6, 16), [Event('OCCULTATION', [ASTERS[1], ASTERS[5]], datetime(2005, 6, 16, 6, 31))]),
+
+        (date(2020, 4, 7), [Event('MOON_PERIGEE', [ASTERS[1]], datetime(2020, 4, 7, 18, 14))]),
+
+        (date(2020, 1, 29), [Event('MOON_APOGEE', [ASTERS[1]], datetime(2020, 1, 29, 21, 32))])
     )
 
     @data_provider(expected_events_provider)
     def test_search_events(self, d: date, expected_events: [Event]):
         actual_events = events.search_events(d)
         self.assertEqual(len(expected_events), len(actual_events),
-                         'Expected %d elements, got %d for date %s.' % (len(expected_events),
-                                                                        len(actual_events),
-                                                                        d.isoformat()))
+                         'Expected %d elements, got %d for date %s.\n%s' % (len(expected_events),
+                                                                            len(actual_events),
+                                                                            d.isoformat(),
+                                                                            actual_events))
 
         for i, expected_event in enumerate(expected_events):
             actual_event = actual_events[i]