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- Sky2Pix_ZenithalEqualArea

# Sky2Pix_ZenithalEqualArea

class astropy.modeling.projections.Sky2Pix_ZenithalEqualArea(*args, **kwargs)

  Bases: `Sky2PixProjection`, `Zenithal`

  Zenithal equidistant projection - sky to pixel.

  Corresponds to the `ZEA` projection in FITS WCS.

  See `Zenithal` for a definition of the full transformation.

  \[\begin{split}R_\theta &= \frac{180^\circ}{\pi} \sqrt{2(1 - \sin\theta)} \\ &= \frac{360^\circ}{\pi} \sin\left(\frac{90^\circ - \theta}{2}\right)\end{split}\]