def to_sky(self, wcs, mode='all'):
        """
        Convert the aperture to a `SkyEllipticalAnnulus` object defined
        in celestial coordinates.

        Parameters
        ----------
        wcs : `~astropy.wcs.WCS`
            The world coordinate system (WCS) transformation to use.

        mode : {'all', 'wcs'}, optional
            Whether to do the transformation including distortions
            (``'all'``; default) or only including only the core WCS
            transformation (``'wcs'``).

        Returns
        -------
        aperture : `SkyEllipticalAnnulus` object
            A `SkyEllipticalAnnulus` object.
        """

        sky_params = self._to_sky_params(wcs, mode=mode)
        return SkyEllipticalAnnulus(**sky_params)
Convert the aperture to a `SkyEllipticalAnnulus` object defined
        in celestial coordinates.

        Parameters
        ----------
        wcs : `~astropy.wcs.WCS`
            The world coordinate system (WCS) transformation to use.

        mode : {'all', 'wcs'}, optional
            Whether to do the transformation including distortions
            (``'all'``; default) or only including only the core WCS
            transformation (``'wcs'``).

        Returns
        -------
        aperture : `SkyEllipticalAnnulus` object
            A `SkyEllipticalAnnulus` object.