Fun fact:
The "Popping in of HD textures" bug in Space Engine has happened a lot of times in many versions (for Intel users is very common).
While
reading this, I just remembered that the first time I saw the
Aristarchus Plateau in SE (when I was totally ignorant about anything related to
Selenography) I just thought that it was a huge patch of HD texture added badly to the surface of the Moon. There was not the slight attempt from my computer or the author of the lunar texture to blend this region naturally with the rest.
Then one day I looked through a telescope and instantly realized it is really like that in the real world! Many of you are probably aware of this but for me it was mind bending. A feature in the Moon that looks totally unrealistic and computer rendered. Here you have some amateur and LRO pictures of what I mean.
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Look at the upper left corner of the region in the last image. Is such an abrupt change in geology and is all bounded by such a seemingly artificial rectangular shape that it fooled me completly at that time.