VLA LST Calculator

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VLA LST Calculator

This is a short script that converts a time to Local Apparent Sidereal Time (LAST) at the VLA. This script can easily be modified to work for other observatories recognized by CASA's 'measures' toolkit. This version reports the current time, and sunrise and sunset on the current day.

t1 = me.epoch('utc', 'today')
me.doframe(me.observatory('VLA'))
me.doframe(t1)
t2 = me.measure(t1,'LAST')

d1=me.riseset(me.direction('sun'))
t_rise = d1['rise']['last']
t_set = d1['set']['last']

print('LST now: '+qa.time(qa.sub(t2['m0'],qa.floor(t2['m0'])), prec=7))
print('LST sunrise: '+qa.time(qa.sub(t_rise['m0'],qa.floor(t_rise['m0'])),prec=7))
print('LST sunset: '+qa.time(qa.sub(t_set['m0'],qa.floor(t_set['m0'])),prec=7))