Semi-square

A semi-square occurs when two planets are 45 degrees apart — exactly half of a square. It is read as a minor hard aspect: the two energies produce friction, but at a lower intensity than the full square. Orbs are tight, typically 2 degrees. Semi-squares are most useful in detailed natal work where they cluster with other tense aspects to reveal a chronic friction theme, and in transit work where a slow planet's semi-square to a natal point can produce a slow simmer of irritation that doesn't quite reach the volume of a square. Modern astrology, particularly in the cosmobiology tradition, takes semi-squares more seriously than mainstream Western astrology does.