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- Pix2Sky_Gnomonic

# Pix2Sky_Gnomonic

class astropy.modeling.projections.Pix2Sky_Gnomonic(*args, **kwargs)

  Bases: `Pix2SkyProjection`, `Zenithal`

  Gnomonic projection - pixel to sky.

  Corresponds to the `TAN` projection in FITS WCS.

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

  \[\theta = \tan^{-1}\left(\frac{180^{\circ}}{\pi R_\theta}\right)\]