Sky2Pix_HammerAitoff#

class astropy.modeling.projections.Sky2Pix_HammerAitoff(*args, **kwargs)[source]#

Bases: Sky2PixProjection, PseudoCylindrical

Hammer-Aitoff projection - sky to pixel.

Corresponds to the AIT projection in FITS WCS.

$$\begin{array}{rl}x& =2\gamma \cos \theta \sin \frac{\varphi }{2}\\ y& =\gamma \sin \theta \end{array}$$

where:

$$\gamma =\frac{{180}^{\circ }}{\pi }\sqrt{\frac{2}{1+\cos \theta \cos (\varphi /2)}}$$