Since we live in the Northern Hemisphere of our planet, we always look at space from a certain angle, so we are familiar with a specific view of the Moon.
If you never travel outside the Northern Hemisphere; If you’re only in Europe, North America, Asia, and the North Pole, you’ll almost always see the Moon in the same shape. When you go to the Southern Hemisphere, that is, places like South America, South Africa, Australia or New Zealand, you will notice that the Moon appears upside down. Likewise, if you’re used to the sky visible in the Southern Hemisphere, you’ll see the Moon upside down when you move to the Northern Hemisphere.
Since the Moon is often seen as it is in the Northern Hemisphere in photographs or movies, there is a perception that it looks like this everywhere on Earth.
Looking at the Moon from the Northern Hemisphere has no privileges over looking from the Southern Hemisphere. But since we have defined the North as the “up” direction throughout history, we have always depicted the celestial bodies from our point of view. For this reason, when viewed from the Northern Hemisphere, it seems normal to us to see the Moon as straight rather than upside down and to transfer it to the drawings in this way.
If someone living at the North Pole stands facing “up”, and another person at the South Pole is standing with the head facing “up” relative to the earth beneath their feet, then they will both have their heads facing completely opposite directions.
A person living at the North Pole would see a bright Moon with a dark upper part and a light lower part. For someone facing the South Pole with their head in a different direction, the dark regions of the Moon would appear this time with the bright part at the top, while the dark regions of the Moon would appear on the lower side.
If they were to move from the North and South Poles towards the Equator, they would find the Moon rotated relative to them, as their “up” direction would change due to the Earth’s tilt.
If the person at the North Pole wanted to see the sky from the point of view of the person at the South Pole, and not leave the North Pole, he would literally have to do a handstand. But standing like this, he couldn’t see what someone standing in the Southern Hemisphere sees because of the Earth’s inclination.
Let’s imagine two people standing 45 degrees north of the Equator (middle between the North Pole and the Equator) and living 45 degrees south of the Equator (middle between the South Pole and the Equator). On the ground, both face “up” but at 90 degrees to each other. If two Moon observers were able to swap places, they would say that the Moon rotated about 90 degrees. This is exactly the same as the phenomenon of shifting perspective described in the North and South Pole example above.
When a hemisphere change is made, the appearance of the entire sky changes, not just the Moon.
Some northern constellations cannot be observed from the south. But Orion, one of the easiest to spot and brightest constellations in the northern winter sky, can be seen from both hemispheres. Just like the image of the Moon, the Orion Constellation’s direction and shape relative to the background stars will change depending on the position of the observer on Earth.