Hello!
Have you ever wondered that why do Sun, Moon
and other objects which are far from us, seem to be moving as we move?
This happens due to the Parallax Effect .
You will come to know about whole of this topic today…so let’s start!
Parallax is an appearant change in the position of an object when viewed from two different view points.
It is measured by an ANGLE between the two view points. Let’s call this angle- angle d in the following figure 
In the above diagram, it’s clear that if we want to keep looking at the object, we will need to turn our head when we move from A to B. This angle of our head turn is equal to angle ‘‘d’’.
So, as far the object is, smaller the angle of our head turn will be.
Hope…it’s clear 
So, now we have got our answer that why the moon seem to move with us…
It’s because moon is about 3,84,000 km away from us!
That’s a quite huge distance. As a result the parallax angle is quite small, means the head turn will also be small.
Fun Fact- The angle of our head turn is just 2° if we move from North Pole to South Pole while keeping a look at the moon.
Thus, because of such small angle of our head turn…it creates an illusion in which we feel that the moon is moving with us!
Yes, that’s the answer to the question that rarely comes to our mind!!
Thank You! 