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: 2024/09/03 20:25:59.812 (台灣標準時)
astroplan を使って、与えられた場所での与えられた時間で天体が見えるかど うか判定するには以下のようにすればよいようでござる。指定した天体が地平 線よりも上にあるのか、下にあるのかを調べてくれるようでござる。
#!/usr/pkg/bin/python3.9 # # Time-stamp: <2022/07/03 10:28:13 (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 = "visibility check at given location" 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') parser.add_argument ('target', nargs='+', help='names of targets') # 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 list_target = args.target # 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 ("# Targets:") for target in list_target: print ("# %s" % target) 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') # processing target one-by-one for target in list_target: # getting object from name obj = astroplan.FixedTarget.from_name (target) # checking visibility of the object visibility = observer.target_is_up (datetime, obj) # printing result if (visibility): print ("%-16s ==> %s" % (target, 'visible') ) else: print ("%-16s ==> %s" % (target, 'not visible') )
実行してみると、以下のようになるでござる。
% ./astroplan_sample_02.py -h usage: astroplan_sample_02.py [-h] [-l LONGITUDE] [-b LATITUDE] [-a ALTITUDE] [-t DATETIME] target [target ...] visibility check at given location positional arguments: target names of targets 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_02.py -t 2022-07-03T12:00:00 Betelgeuse Sirius Procyon \ ? Arcturus Spica Vega Altair Deneb Antares Fomalhaut # # input parameters # # Location: # longitude = +121d11m12s # latitude = +24d58m12s # altitude = 151.6 m # Date/Time: # date/time (UT) = 2022-07-03T12:00:00 # Targets: # Betelgeuse # Sirius # Procyon # Arcturus # Spica # Vega # Altair # Deneb # Antares # Fomalhaut # Betelgeuse ==> not visible Sirius ==> not visible Procyon ==> not visible Arcturus ==> visible Spica ==> visible Vega ==> visible Altair ==> visible Deneb ==> visible Antares ==> visible Fomalhaut ==> not visible