Sun Opposition Moon in Depth
The Full Moon geometry
One hundred eighty degrees puts Sun and Moon on opposite sides of the wheel, facing each other across the chart. You were born at or near a Full Moon, which means the Moon was fully illuminated by the Sun. That image is the aspect. Your feelings are extremely visible to you and to others, because your solar will is shining directly on them. Nothing about your emotional life stays subtle.
Standard orb runs seven to nine degrees. The opposition also guarantees your Sun and Moon sit in signs of the same modality but opposite elements, fire with air or earth with water, so the tension is between two compatible temperaments pulling in incompatible directions rather than two things that simply cannot speak.
Relationships as the arena
Oppositions almost always get projected. The half of the pair you are less comfortable owning gets handed to whoever is closest. In practice this often looks like choosing partners who carry your Moon sign qualities so you can stay identified with your Sun, then feeling smothered or unmet by exactly the trait you outsourced. Somebody with a Leo Sun and Aquarius Moon may keep dating cool, detached people and then complain about the coolness.
The turn comes when you stop looking for a person who completes the axis and start alternating consciously between the two ends yourself. That usually means building a weekly rhythm that feeds both, not a compromise that half feeds each. Notice which end of the axis you describe as the real you, because that is usually the half that has been getting all the practice while the other half waits.
How it ages
This is one of the aspects that improves most reliably with time. Young people with a Sun-Moon opposition tend to swing, decisive one week and withdrawn the next, and read the swing as instability. By the late thirties, after the first Saturn return has forced some structure onto it, the same swing tends to be reframed as range. The capacity to argue both sides of a question honestly is unusual and professionally valuable in mediation, editing, negotiation, and any work that requires holding two viewpoints at once.
Timing and what to do
Every Full Moon activates the pattern to some degree, but the ones that fall on your natal Sun-Moon axis, roughly twice a year, are the loud ones. Expect something you have been quietly holding to become undeniable within a day or two of exact.
The workable practice is simple and slightly boring. When you feel the pull, name both sides out loud or on paper before acting on either. Written down, the two positions usually turn out to be about ninety percent compatible, and the fight was over the remaining ten. This is reflective practice, not therapy, and a real conflict with someone still needs a real conversation.