1) Originally, I had planned to have something cool happen during solar and lunar eclipses. The two icons in the middle represent points where the circle of the moon's orbit crosses the circle of the suns' orbit (the ecliptic). In astronomy and astrology, those points are called the head and the tail of the dragon. When one of them lines up exactly with the sun and the moon simultaneously, an eclipse occurs. Right now, they don;t do anything!

2) Good suggestions. Yes, I will be adding some contextual info (possibly with tooltips) to have the whole things make more sense.