The T-Square
Think of a pressure cooker. Steam builds and builds, and it has to come out somewhere, so it is released through one valve, with force. That is a T-square: two planets pulling against each other, and a third where all that tension comes out.
A T-square is three planets: two facing each other in opposition, and a third, the apex, square to both. Drawn on the wheel, it looks like a T, or a triangle with a right angle.
T-Square. An opposition with a third planet square to both. The tension gathers at the apex planet, which becomes the outlet and the drive.
How to spot it
Look for an opposition (a long red line across the chart) with a third planet roughly halfway between its two ends, linked to both by squares. Check the signs: a classic T-square has all three planets in the same modality.
The missing leg
Here is a detail astrologers love. A T-square is three corners of a square cross, with one corner empty. That empty point, directly opposite the apex, is called the missing leg. Astrologers often find that developing the qualities of the sign and house of the missing leg is what eases the tension, giving the pressure somewhere to go other than straight out through the apex.
- Planets
- 3
- Built from
- 1 opposition, 2 squares
- Usually in
- One modality

Is there a pattern in your chart?
Grand trines, T-squares, stelliums: see which shapes your planets make.


