What is a sesquiquadrate in astrology?

A minor aspect of 135 degrees. One and a half squares (135°). Classified as inharmonious. Adds friction similar to the semisquare. Modern reading: agitating tension late in a developmental cycle. Pressure to express or resolve.

How is the sesquiquadrate angle of 135 degrees derived?

135 degrees is derived from dividing the circle into 5 parts and taking an odd multiple. Aspects are ratios of the circle rather than arbitrary distances, which is why the minor set is small: the minor aspects come from the simplest divisions, and each further subdivision produces a narrower, more contested aspect.

What orb should a sesquiquadrate use?

This site uses 2 degrees by default for the sesquiquadrate. Orb is a convention, not a measured quantity: there is no agreed value, practitioners commonly tighten orbs for minor aspects and for slow-moving bodies, and some assign orb to the planets involved rather than to the aspect. Widen the orb and more aspects appear; narrow it and the same chart looks sparse. Any aspect list is therefore only comparable to another when both state the orb used.

Is the sesquiquadrate a good or bad aspect?

Classical sources class the sesquiquadrate as tense. That describes friction between the two bodies, not a verdict: tense aspects are where most sources locate motivation and development, and a chart with none is not a better chart.

Sesquiquadrate

135°·tense·minor·default orb ±2°

Classical source

One and a half squares (135°). Classified as inharmonious. Adds friction similar to the semisquare.

Modern Western reading

Modern reading: agitating tension late in a developmental cycle. Pressure to express or resolve.

Sesquiquadrate between two planets

Cited reference for this aspect between each pair of planets. Inner-planet pairs only list aspects their orbits can actually form.

Other aspects

Questions

What is a sesquiquadrate in astrology?: A minor aspect of 135 degrees. One and a half squares (135°). Classified as inharmonious. Adds friction similar to the semisquare. Modern reading: agitating tension late in a developmental cycle. Pressure to express or resolve.
How is the sesquiquadrate angle of 135 degrees derived?: 135 degrees is derived from dividing the circle into 5 parts and taking an odd multiple. Aspects are ratios of the circle rather than arbitrary distances, which is why the minor set is small: the minor aspects come from the simplest divisions, and each further subdivision produces a narrower, more contested aspect.
What orb should a sesquiquadrate use?: This site uses 2 degrees by default for the sesquiquadrate. Orb is a convention, not a measured quantity: there is no agreed value, practitioners commonly tighten orbs for minor aspects and for slow-moving bodies, and some assign orb to the planets involved rather than to the aspect. Widen the orb and more aspects appear; narrow it and the same chart looks sparse. Any aspect list is therefore only comparable to another when both state the orb used.
Is the sesquiquadrate a good or bad aspect?: Classical sources class the sesquiquadrate as tense. That describes friction between the two bodies, not a verdict: tense aspects are where most sources locate motivation and development, and a chart with none is not a better chart.

Reference, not advice

This is cultural and astronomical reference, not personal prediction or advice.

Aspect classifications follow classical Western convention. Different traditions assign slightly different orb budgets - the values shown are conservative defaults used throughout this site.

Sources

Ptolemy, Tetrabiblos

Last reviewed 2026-05-28.