def lunar_parallax(self, tee):
"""Return the parallax of moon at moment, tee, at location, location.
Adapted from "Astronomical Algorithms" by Jean Meeus,
Willmann_Bell, Inc., 1998."""
geo = self.lunar_altitude(tee)
Delta = Lunar.lunar_distance(tee)
alt = 6378140 / Delta
arg = alt * cos_degrees(geo)
return arcsin_degrees(arg)
