ephem_notes.txt

sudo apt-get install python-dev
sudo apt-get install python-pip

sudo pip install ephem

import ephem

#Make an observer
fred      = ephem.Observer()

#PyEphem takes and returns only UTC times. 15:00 is noon in Fredericton
#fred.date = "2013-09-04 15:00:00"
fred.date = date

#Location of Fredericton, Canada
fred.lon  = str(-66.666667) #Note that lon should be in string format
fred.lat  = str(45.95)      #Note that lat should be in string format

#Elevation of Fredericton, Canada, in metres
fred.elev = 20

#To get U.S. Naval Astronomical Almanac values, use these settings
fred.pressure= 0
fred.horizon = '-0:34'

sunrise=fred.previous_rising(ephem.Sun()) #Sunrise
noon   =fred.next_transit   (ephem.Sun(), start=sunrise) #Solar noon
sunset =fred.next_setting   (ephem.Sun()) #Sunset

#We relocate the horizon to get twilight times
fred.horizon = '-6' #-6=civil twilight, -12=nautical, -18=astronomical
beg_twilight=fred.previous_rising(ephem.Sun(), use_center=True) #Begin civil twilight
end_twilight=fred.next_setting   (ephem.Sun(), use_center=True) #End civil twilight

print "sunrise: " + str(sunrise)
print "sunset:  " + str(sunset)