If you find the Graffiti Room at Tertoliod's Observatory, you will receive an Increase of 2 points to Astrology and 1 point to both Astronomy and Art - but only for the duration of your stay.
If you happen upon it, make sure you go to the Graffiti Room before you leave Tertoliod's Observatory. Over the centuries, astrologers have gone to the room to share ideas and literally leave their mark for future students. Carefully inspect the carvings in the wood, and you will see that messages have been left about comets that only streak by Choris every 200 years, easier methods for calculating a star's hour angle, and uncharted segments of the sky. The visit is its own Astrology Lecture, something well worth attending for its own sake.