def moonage(d, d1): # used in twilighttab (section 3)
# return the moon's 'age' and percent illuminated
# percent illumination is calculated at noon
t12 = ts.ut1(d.year, d.month, d.day, 12, 0, 0)
phase_angle = almanac.phase_angle(eph, 'moon', t12)
pctrad = 50 * (1.0 + math.cos(phase_angle.radians))
pct = "{:.0f}".format(pctrad)
# calculate age of moon
pnm = PreviousNewMoon
nnm = NextNewMoon
#dt0 = datetime.date(pnm.year, pnm.month, pnm.day)
#dt1 = datetime.date(nnm.year, nnm.month, nnm.day)
dt = datetime.datetime.combine(d1, datetime.time(0, 0))
age1td = dt - pnm.replace(tzinfo=None)
age2td = dt - nnm.replace(tzinfo=None)
age1 = age1td.days
age2 = age2td.days
age = age1
if age2 >= 0:
age = age2
return age, pct
def moonphase(d): # used in twilighttab (section 3)
# returns the moon's elongation (angle to the sun)
# convert python 'date' to 'date with time' ...
dt = datetime.datetime(d.year, d.month, d.day, 0, 0, 0)
# phase is calculated at noon
dt += datetime.timedelta(hours=12)
t12 = ts.ut1(d.year, d.month, d.day, 12, 0, 0)
phase_angle = almanac.phase_angle(eph, 'moon', t12)
elong = phase_angle.radians
# phase_angle.degrees is ...
# 180 at New Moon, drops to 0 at Full Moon, then rises to 180 at New Moon
#pnm = PreviousNewMoon.replace(tzinfo=None)
#nfm = NextFullMoon.replace(tzinfo=None)
#pfm = PreviousFullMoon.replace(tzinfo=None)
#nnm = NextNewMoon.replace(tzinfo=None)
if WaxingMoon:
phase = math.pi - phase_angle.radians
else:
phase = math.pi + phase_angle.radians
return phase
def equation_of_time(d, d1, UpperList, LowerList,
extras): # used in twilighttab (section 3)
# returns equation of time, the sun's transit time,
# the moon's transit-, antitransit-time, age and percent illumination.
# (Equation of Time = Mean solar time - Apparent solar time)
t00 = ts.ut1(d.year, d.month, d.day, 0, 0, 0)
position = earth.at(t00).observe(sun)
ra = position.apparent().radec(epoch='date')[0]
gha00 = gha2deg(t00.gast, ra.hours)
eqt00 = gha2eqt(gha00)
if gha00 <= 180:
eqt00 = r"\colorbox{{lightgray!80}}{{{}}}".format(eqt00)
# percent illumination is calculated at noon
t12 = ts.ut1(d.year, d.month, d.day, 12, 0, 0)
position = earth.at(t12).observe(sun)
ra = position.apparent().radec(epoch='date')[0]
gha12 = gha2deg(t12.gast, ra.hours)
eqt12 = gha2eqt(gha12)
mpa12 = gha2mpa(gha12)
if gha12 > 270:
eqt12 = r"\colorbox{{lightgray!80}}{{{}}}".format(eqt12)
# !! transit times are rounded to the nearest minute,
# !! so the search needs to start and end 30 sec earlier
# !! e.g. after 23h 59m 30s rounds up to 00:00 next day
# calculate moon upper transit
mp_upper = find_transit(d, UpperList, False)
# calculate moon lower transit
mp_lower = find_transit(d, LowerList, True)
if not (extras): # omit 'age' and 'pct'
return eqt00, eqt12, mpa12, mp_upper, mp_lower
phase_angle = almanac.phase_angle(eph, 'moon', t12)
pctrad = 50 * (1.0 + math.cos(phase_angle.radians))
pct = "{:.0f}".format(pctrad)
# calculate age of moon
pnm = PreviousNewMoon
nnm = NextNewMoon
#dt0 = datetime.date(pnm.year, pnm.month, pnm.day)
#dt1 = datetime.date(nnm.year, nnm.month, nnm.day)
dt = datetime.datetime.combine(d1, datetime.time(0, 0))
age1td = dt - pnm.replace(tzinfo=None)
age2td = dt - nnm.replace(tzinfo=None)
age1 = age1td.days
age2 = age2td.days
age = age1
if age2 >= 0:
age = age2
return eqt00, eqt12, mpa12, mp_upper, mp_lower, age, pct