This placement
Your mind is a delicate scale — analytical, meticulous, systematic; you catch the single error in a text, the single gap in a plan, instantly. You're at the peak of practical intelligence: you organize, filter and make knowledge usable. Your strength is your clarity, your logic and your mastery of detail; your weakness is excessive criticism (of yourself and others), obsessive perfectionism, and the "what if it's wrong" worry. Your test: accepting good enough, balancing criticism with compassion.
What does “domicile” mean?
The planet is in its own sign: it speaks the same language as the sign. The most natural, most comfortable expression — it works without effort.