I would submit that an accurate answer using basic physics, using no specifics or details of Apollo, is as simple as "thermodynamics" or the (slightly) less accurate "radiation".

Why do you need Jay for this? Wouldn't a basic physics textbook do just as well?

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And you, to whom adversity has dealt the final blow
With smiling [faces] lyin' to ye' everywhere ye' go
Turn to, and put out all your strength of arm and heart and brain
And like the Mary Ellen Carter, rise again.