def dusk_utc(self, date, latitude, longitude, depression=0, observer_elevation=0):
        """Calculate dusk time in the UTC timezone.

        :param date:       Date to calculate for.
        :type date:        :class:`datetime.date`
        :param latitude:   Latitude - Northern latitudes should be positive
        :type latitude:    float
        :param longitude:  Longitude - Eastern longitudes should be positive
        :type longitude:   float
        :param depression: Override the depression used
        :type depression:   float
        :param observer_elevation:  Elevation in metres to calculate dusk for
        :type observer_elevation:   int

        :return: The UTC date and time at which dusk occurs.
        :rtype: :class:`~datetime.datetime`
        """

        if depression == 0:
            depression = self._depression
        depression += 90

        try:
            return self._calc_time(depression, SUN_SETTING, date, latitude, longitude, observer_elevation)
        except ValueError as exc:
            if exc.args[0] == "math domain error":
                raise AstralError(
                    (
                        "Sun never reaches %d degrees below the horizon, "
                        "at this location."
                    )
                    % (depression - 90)
                )
            else:
                raise
Calculate dusk time in the UTC timezone.

        :param date:       Date to calculate for.
        :type date:        :class:`datetime.date`
        :param latitude:   Latitude - Northern latitudes should be positive
        :type latitude:    float
        :param longitude:  Longitude - Eastern longitudes should be positive
        :type longitude:   float
        :param depression: Override the depression used
        :type depression:   float
        :param observer_elevation:  Elevation in metres to calculate dusk for
        :type observer_elevation:   int

        :return: The UTC date and time at which dusk occurs.
        :rtype: :class:`~datetime.datetime`