Nutze Skyfield fuer praezisere Daemmerungsberechnung

public/py/vendor/skyfield/__main__.py

@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+
+import numpy as np
+
+import jplephem
+import sgp4
+import skyfield
+from skyfield.api import load
+from skyfield.functions import load_bundled_npy
+
+def main():
+    print('Skyfield version: {0}'.format(skyfield.__version__))
+    print('jplephem version: {0}'.format(jplephem.__version__))
+    print('sgp4 version: {0}'.format(sgp4.__version__))
+
+    ts = load.timescale()
+    fmt = '%Y-%m-%d'
+
+    final_leap = (ts._leap_tai[-1] - 1) / (24 * 60 * 60)
+    print('Built-in leap seconds table ends with leap second at: {0}'
+          .format(ts.tai_jd(final_leap).utc_strftime()))
+
+    arrays = load_bundled_npy('iers.npz')
+    daily_tt = arrays['tt_jd_minus_arange']
+    daily_tt += np.arange(len(daily_tt))
+    start = ts.tt_jd(daily_tt[0])
+    end = ts.tt_jd(daily_tt[-1])
+    print('Built-in ∆T table from finals2000A.all covers: {0} to {1}'
+          .format(start.utc_strftime(fmt), end.utc_strftime(fmt)))
+
+main()