What is the Sesquiquadrate (135°) Aspect?

The sesquiquadrate (sesquisquare, 135°) is a minor aspect that is three times the semi-square (45°); it carries a dynamic similar to a square that challenges and creates tension, but its effect is weaker.

What Does Sesquiquadrate Mean?

• Tension and Change: It creates a dynamic bond that challenges like a square — but with less intensity than a square.
• Narrow Orb, High Activity: It is usually defined with a small orb (~2°); despite being narrow, it can exhibit a distinct and productive effect in practice.
• Relationship to the Semi-Square: It is directly related to the semi-square (45°) — it arises from its triplet (3×45°) and carries similar themes such as irritation, tension, and activity.
• Variable Intensity by Individual: While it can produce significant issues in some charts, in others it may be almost imperceptible — a common characteristic of minor aspects.

How to Interpret the Sesquiquadrate in Your Chart?

• Relevant Planets: Start with the natural functions of the planets; assess which inner or outer areas the tension created by the aspect pressures.
• Transit Overlap: Check whether the aspect is a transit and if it intersects with other minor aspects or a major transit simultaneously — the overlap significantly strengthens the effect.
• Element/Sign Similarity: The element or quality similarity of the signs where the planets are located (e.g., both in earth signs) shapes how the interaction will unfold.
• Watch the Orb: A narrow orb of ~2° is recommended; the effect is felt more distinctly in tight (narrow) aspects.

Things to Keep in Mind

The effect of minor aspects varies greatly from chart to chart; generalizing alone can be misleading — it should be evaluated in conjunction with the whole chart and the planet’s other connections. Detailed psychological descriptions about the sesquiquadrate in resources are limited; existing information is mostly focused on the theme of tension/activity and emergence under transit conditions.

For an overview of its root semi-square (45°) aspect, square, and other fundamental aspects, you can check our articles on Square Aspect and Guide to Aspects in Astrology.