Is this painting made by PS or other software? I want the right answer! Illustrator KAGAYA constellation and cosmic background are also PS, or illustrator?

Hehe, don't worry too much about what software to use. This kind of diagram can be realized by many softwares, depending on what you use. This picture is easy to draw with PS, and Illustrator can't draw it.

There are many drawing softwares. PS belongs to image synthesis software, but many people use it to draw illustrations, and the effect is very good. Painter is recognized as the best painting software at present, and illustrator is vector software, which is different from PS.