"dlzc" wrote in :

.. whereas the far side (with its lack of radiative
heat sink at ~293K) could have gotten much stiffer, sooner.

From the moon, the Earth does not cover very much of the sky.

In any case, the earth is seen as a radiative *source*. It is the empty
black sky that appears as a "sink" (~4 Kelvin).

The sun is seen pretty much the same from both sides of the moon,
notwithstanding relatively rare eclipses.

--
http://pages.videotron.ca/duffym/usenet.htm#s.p