Greetings

Astronomy for Astrologers

7. In fact, the direction of 0° Cancer is defined by the
   direction toward which the North Pole is tilted in the
   Tropical zodiac.

The Earth's Tilt

The important idea so far is that the axis of the Earth is
frozen or fixed in space, no matter where the Earth
happens to be in its orbit around the Sun. Here are
some other facts to consider in relation to these same
diagrams:

1. The seasons result from the 'tilt' of the North Pole into
   or toward the Sun.


2. At the moment of the summer solstice, the North Pole
   is tilted most toward the Sun and therefore is aligned
   with a vertical light ray coming from the Sun.