Moon phase seems inconsistent: Getting values over 180 degrees

[JsBergbau]

According to https://rhodesmill.org/skyfield/almanac.html#phases-of-the-moon 0 degrees is new moon, 180 degress is full moon.

Trying with this script

from datetime import datetime
from dateutil import tz
from skyfield import almanac

planets = load('de421.bsp')

#Next full moon
ts = load.timescale()
time=datetime(2022,6,14,1,48,tzinfo=tz.tzoffset("DE",7200))
timets=ts.from_datetime(time)
moonphase = almanac.moon_phase(planets,timets)
print("Moonphase: " ,time, ": " , moonphase)

#about one month later
time=datetime(2022,7,18,1,48,tzinfo=tz.tzoffset("DE",7200))
timets=ts.from_datetime(time)
moonphase = almanac.moon_phase(planets,timets)
print("Moonphase: " ,time, ": " , moonphase)

I get

Moonphase:  2022-06-14 01:48:00+02:00 :  172deg 51' 21.5"
Moonphase:  2022-07-18 01:48:00+02:00 :  238deg 03' 32.6"

172 degrees seem reasonable, but why is there 238 degress for about one month later?

[brandon-rhodes]

Because the phase is a number from 0°–359.99° that tells you where the Moon is in its whole journey from New to Full to back to New. I'll expand the description there in the docs you link to, to clarify that the angle keeps growing until the end of the lunar month.

[brandon-rhodes]

There! The documentation should update the next time I do a release of Skyfield. Thanks for pointing out that the description of the function was incomplete.