Hi all, It's only a few days to the equinox, which happens here in the middle of the night (3:35 AST). I'm going to use the previous evening and following morning to use a pole's shadow to make myself an East-West line, to compare to my existing NS meridian line. I hope to find that they are at right angles to each other.
The moon becomes fully full just hours earlier, at 0:44 AST, so I'm wondering if I can do the East-West thing by moonlight too. Is it a valid thing to try? I've got a suspicion it only works when the equinox is also an eclipse, so that all the bodies are all in the same plane. If that is so, does the phase of the moon have any relevance, other than giving a strong shadow? Unfortunately, my understanding isn't good enough to answer my own questions. And are there any other special sundial-related phenomena which I should be looking out for? Steve
