Cameron Moran of Queenstown asks :-
Why are the Sun and Moon visible from both sides of the equator?
Alan Gilmore, an astronomer at the University of Canterbury's Mt John Observatory, responded.
The sun, or the moon, is visible from half the earth at any one time, because it is so very far away. The equator points toward the sun, roughly speaking. So sunlight shines on both sides of the equator at the same time.
The earth's axis is tilted in its orbit. So sometimes the sun shines more on one hemisphere than on the the other. In our winter the sun shines more on the northern hemisphere. Then places near the north pole have the 'midnight sun'. At the same time the south pole and places like Scott Base in Antarctica are in continuous darkness.
In our summer the sun shines all the time on the south pole while north pole places are in darkness all the time.
The same thing happens with the moon except that it sometimes ranges further north and further south than the sun. We expect to see a full moon in our sky every month. Places near the south pole don't see a full moon in our summer because the moon is too far north. That doesn't matter because they have the sun all day anyway. In the Antarctic winter they have the full moon continuously in the sky.