On ye fifthe daye of Christmas:
The ecliptic has two blind spots. What are they? and why are they blind?
- Why they are the Vertex and the Antivertex. They have turned around so much that their ‘eyes’ are focused on each other and so can’t ‘see’ anything else. By analogy it is like being folded down the middle so that the eyes look at each other.
- These are the deferent and the equant. Ptolomy called them ‘blind’ because they are not visible.
- These are the points where the Moon crosses the ecliptic. They are ‘blind’ because when the Sun and Moon are near them during a Full or New Moon there is an eclipse. The Lights darken or are blinded. They are not functionally but effectually blind!
- Why the nodes of course. Could you see if you had one of them sitting on your nose?