ASPECT PATTERN When three or more PLANETS are connected to each other by aspect they form a pattern with a meaning of its own. 'T' SQUARE:
Two PLANETS in opposition are both in square to a third PLANET. This brings tension and sharp, pressing problems the result of which may be great energy and consequently a better than average chance of success throughout life.
When interpreting a T' Square all the factors involved - planets, signs and houses - must be taken separately and then built up into a picture of the choices, difficulties and solutions which each planet suggests.
When the 'T' Square is in:
Cardinal Signs, there is exceptional dynamism and energy Fixed Signs, people may be excessively stubborn fighting personal battles to the bitter end.
Mutable Signs, they may try to solve, or even avoid the problems associated with the 'T' Square by being flexible and adaptable.
Solution to the 'T' Square
A: via harmonious Aspects.
The tension of the 'T' Square can be released or positively expressed through the planet which makes the closest sextile or trine to any of the three planets in the 'T' Square. In this example the emotional tension of the Sun-Mars-Saturn 'T' Square can be released through the sextile to Jupiter in Cancer
Along with JA's comment that only bodies form planetary configurations like the t-square, part of the challenge [like a t-square] or harmony [like a grand trine] of the configuration is based on the challenge or harmony of the signs involved.
In your case, Uranus trines Mars by sign, so there is harmony there, even if you want o allow for a 6 degree orb to call it a square, which is pretty wide anyway for an aspect from Mars to with an outer planet.
And out-of-sign aspect excludes it from the force of planetary configuration.