Yeah, turns out I was looking at base temperature instead of surface temperature, so Mars was hot as an oven.
A related question; do Greenhouse Gases dissipate over time? I think I remember in past games where planets I thought were terraformed lost their greenhouse gasses resulting in insufficient atmosphere pressure.
Also, does accuracy apply to every shot a weapon makes or just every volley? For instance, will a Gauss cannon shooting 3 rounds with 25% accuracy have a sperate 25% chance to hit with each one of those rounds?