They were all bundled in heavy garments, for the temperature of Callisto, never high, frequently drops to sub-zero readings.
The sub-zero temperature of Meta's voice left no doubt as to what she wanted to do with her.
The Wing Commander stiffened and snorted like a Merlin backfiring on a sub-zero morning.
We have since found that it can and does heat the entire house even at sub-zero temperatures.
During the day the heat would boil eggs, and at night the sub-zero cold cracked great scales off the granite boulders.