I like noticing things…

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For instance, this is the just after full moon. Its in the same place in the sky as it was over the last few days, but not at the same time! I know the Earth and Moon orbit each other, and the moon is tidally locked with us. Which means it has one side always facing towards us. But as I say its in about the same place, but each day its a bit later, so after 5 days it’s moved from being there at 2am to 6am…..

Think about it. The Earth rotates in 24 hours, if the Moon is coming up later each day it must be going round the Earth at a certain speed. I don’t have the mathematic skill to work that out but if it takes 6 days to move 4 hours then if you multiply 4×6 you get 24 (hours) for it to end up in the same place so if you multiply 5(days)x6 you get 30, which is approximately a month to get to the same place in the sky and appear again at 2am. The Moon waxes and wanes while doing this. From that you can tell approximately where the sun is in relationship to us. If the half moon, and all the other phases are facing one way before full moon, the Sun is on the lighter side of the Moon. If its curved the other way as the moon starts to go away from full, then it’s on the other side. You can guess when the sun will rise from this, the smaller the area of brightness the more to the side of the Earth the sun must be. I can’t work out whether the sun would be rising sooner or later depending on its phase. I can see in my mind that if you were looking at both Earth and Moon from space they would be lit from the same direction, but sometimes you see the Moon in daylight, so I don’t know how that works. I think I would need to start drawing very long thin triangles, based on say a quarter of a centimeter on one side and 93 centimeters on the other two to work something out (based on the ratio of distances from the Earth to the Moon and the Earth to the Sun – .5:93…this is just scaling down the siz. I’m thinking in miles because I don’t know the distances in kilometers…. Its all got a bit complicated….

I remember once watching the moon every day for a week from the top of the hill, each day it got closer to the setting sun, till finally there was almost an eclipse. Somewhere on Earth there must have been an eclipse in the following day or so, but we missed it because the sun had already set.

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