The other side would radiate, losing the heat. Earth, being in a similar position, is neither incinerated nor refrigerated, though different sides of it can be hot or cold.

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0_____0 8 hours ago | parent [-]

Earth has the benefit of a thermal mass that's at least a couple times larger than your average terrarium.

	▲	nitwit005 3 hours ago \| parent [-]
		Everything exposed to the sun will heat up until the energy it emits balances out the incoming energy. Being a larger mass just means an object will take longer to heat up.