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- Pix2Sky_HammerAitoff

# Pix2Sky_HammerAitoff

class astropy.modeling.projections.Pix2Sky_HammerAitoff(*args, **kwargs)

  Bases: `Pix2SkyProjection`, `PseudoCylindrical`

  Hammer-Aitoff projection - pixel to sky.

  Corresponds to the `AIT` projection in FITS WCS.

  \[\begin{split}\phi &= 2 \arg \left(2Z^2 - 1, \frac{\pi}{180^\circ} \frac{Z}{2}x\right) \\ \theta &= \sin^{-1}\left(\frac{\pi}{180^\circ}yZ\right)\end{split}\]