Sky2Pix_HammerAitoff

class astropy.modeling.projections.Sky2Pix_HammerAitoff(*args, **kwargs)

Bases: Sky2PixProjection, PseudoCylindrical

Hammer-Aitoff projection - sky to pixel.

Corresponds to the AIT projection in FITS WCS.

\[\begin{split}x &= 2 \gamma \cos \theta \sin \frac{\phi}{2} \\ y &= \gamma \sin \theta\end{split}\]

where:

\[\gamma = \frac{180^\circ}{\pi} \sqrt{\frac{2}{1 + \cos \theta \cos(\phi / 2)}}\]