これは日々の作業を通して学んだことや毎日の生活で気づいたことをを記録しておく備忘録である。
HTML ファイル生成日時: 2024/12/21 11:44:57.596 (台灣標準時)
astroplan を使って、薄明の終了と開始の時間を調べるには以下のようにすれ ばよいようでござる。市民薄明、航海薄明、天文薄明のいずれも調べることが できるようでござる。
#!/usr/pkg/bin/python3.9 # # Time-stamp: <2022/07/03 10:59:57 (CST) daisuke> # # importing argparse module import argparse # importing astropy module import astropy.units import astropy.time import astropy.coordinates # importing astroplan module import astroplan # units unit_m = astropy.units.m # constructing parser object desc = "finding time of twilight" parser = argparse.ArgumentParser (description=desc) # adding arguments parser.add_argument ('-l', '--longitude', default='+121d11m12s', \ help='longitude of observing site in format "+121d11m12s"') parser.add_argument ('-b', '--latitude', default='+24d58m12s', \ help='latitude of observing site in format "+24d58m12s"') parser.add_argument ('-a', '--altitude', type=float, default=151.6, \ help='altitude above sea-level in metre') parser.add_argument ('-t', '--datetime', default='2000-01-01T12:00:00.000', \ help='date/time in UT in "YYYY-MM-DDThh:mm:ss.sss" format') # command-line argument analysis args = parser.parse_args () # input parameters site_lon = args.longitude site_lat = args.latitude site_alt = args.altitude * unit_m datetime_str = args.datetime # printing input parameters print ("#") print ("# input parameters") print ("#") print ("# Location:") print ("# longitude =", site_lon) print ("# latitude =", site_lat) print ("# altitude =", site_alt) print ("# Date/Time:") print ("# date/time (UT) =", datetime_str) print ("#") # location object location = astropy.coordinates.EarthLocation.from_geodetic \ (site_lon, site_lat, site_alt) # observer object observer = astroplan.Observer (location=location, name="observer", \ timezone="UTC") # time object datetime = astropy.time.Time (datetime_str, scale='utc') # end of twilight twilight_civil_end = observer.twilight_evening_civil \ (datetime, which="nearest") twilight_nautical_end = observer.twilight_evening_nautical \ (datetime, which="nearest") twilight_astronomical_end = observer.twilight_evening_astronomical \ (datetime, which="nearest") # start of twilight twilight_civil_start = observer.twilight_morning_civil \ (datetime, which="nearest") twilight_nautical_start = observer.twilight_morning_nautical \ (datetime, which="nearest") twilight_astronomical_start = observer.twilight_morning_astronomical \ (datetime, which="nearest") # printing results print ("end of evening twilight nearest to %s" % datetime) print (" civil twilight: %s" % twilight_civil_end.isot) print (" nautical twilight: %s" % twilight_nautical_end.isot) print (" astronomical twilight: %s" % twilight_astronomical_end.isot) print ("start of morning twilight nearest to %s" % datetime) print (" civil twilight: %s" % twilight_civil_start.isot) print (" nautical twilight: %s" % twilight_nautical_start.isot) print (" astronomical twilight: %s" % twilight_astronomical_start.isot)
実行してみると、以下のようになるでござる。
% ./astroplan_sample_06.py -h usage: astroplan_sample_06.py [-h] [-l LONGITUDE] [-b LATITUDE] [-a ALTITUDE] [-t DATETIME] finding time of twilight optional arguments: -h, --help show this help message and exit -l LONGITUDE, --longitude LONGITUDE longitude of observing site in format "+121d11m12s" -b LATITUDE, --latitude LATITUDE latitude of observing site in format "+24d58m12s" -a ALTITUDE, --altitude ALTITUDE altitude above sea-level in metre -t DATETIME, --datetime DATETIME date/time in UT in "YYYY-MM-DDThh:mm:ss.sss" format % ./astroplan_sample_06.py -t 2022-07-03T16:00:00 # # input parameters # # Location: # longitude = +121d11m12s # latitude = +24d58m12s # altitude = 151.6 m # Date/Time: # date/time (UT) = 2022-07-03T16:00:00 # end of evening twilight nearest to 2022-07-03T16:00:00.000 civil twilight: 2022-07-03T11:14:44.574 nautical twilight: 2022-07-03T11:45:31.111 astronomical twilight: 2022-07-03T12:17:44.886 start of morning twilight nearest to 2022-07-03T16:00:00.000 civil twilight: 2022-07-03T20:44:29.544 nautical twilight: 2022-07-03T20:13:43.255 astronomical twilight: 2022-07-03T19:41:29.051