Sasaki-san and the halo, revisited

Sasaki-san wondering why he sees the halo at 22° when the triangle between him, the halo and the sun seems to suggest otherwise.

Sasaki-san looks at the halo and wonders why it is at 22° from the sun. He knows that the light’s deflection in the ice (orange angle) is 22°, but the triangle on the figure seems to suggest that he should see the halo at a smaller angle. The explanation is that the sun is so incredibly far away compared to the ice in the atmosphere, that the angle at the sun is effectively 0°.