If you are an amateur astronomer, a student of celestial navigation, or a programmer trying to write code to calculate the position of Jupiter, you have likely hit the same wall.
But the book is dense. It involves spherical trigonometry, Keplerian elements, and rigorous timekeeping standards (like the difference between Terrestrial Time and Universal Time). If you are an amateur astronomer, a student
The Explanatory Supplement is the technical manual for the universe. If you are an amateur astronomer