How can I get a habitable moon of a gas giant to cool once it is in the planet's shadow?

I'm currently heavily revising a story which is largely set on a habitable but not exactly hospitable moon of a gas giant orbiting on the outer edge (or just beyond) of the habitable zone around a Sun-like star. I should note that the moon is not naturally habitable - it was terraformed in the distant past, and its ecosystem is a very simple engineered one.

For plot purposes, I need the moon to support unaided human life but get very cold very quickly when it passes into the gas giant's shadow and ideally stay this way for a day or two by Earth's standards. I've tried to research what factors might allow this to happen - distance to primary, the primary's diameter, inclination, atmospheric density, size of the moon, ocean coverage, cloud layers and so on but I've not been able to find a consistent answer.

How can I design this moon so that it is habitable but will get cold enough quickly enough to pose a significant threat to human life every time it enters the primary's shadow?

There is supposed to be little in the way of inclination so the eclipses are fairly regular events.

posted about 9 years ago

MG1981‭

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