I'm trying to show that for certain combinations of altitude and inclination there will be periods of the year where a satellite has eclipse-free orbits. Using a satellite-centered celestial coordinate system, in which the orbit plane is the equator and the direction of Earth is fixed along the x-axis, how do I calculate the Sun's maximum angle above the orbit plane? I know the altitude, and thus the angular radius of the Earth disc on the sphere. In my book, to get the maximum angle of the Sun above the orbital plane, they simply take the sum of the orbit inclination and the angle between the ecliptic and the Earth's equator (23 deg). This is fine until the orbit inclination > 67 degs, for which the max sun angle would exceed 90 degrees -- which doesn't make sense (to me) if I understand the geometry in the figures of my book correctly. E.g., what if the orbit is a LEO orbit with 100 degrees inclination?