earth-sun distance and heat involved

In article ,
Keith F. Lynch wrote:
Also because 4.8 million out of 150 million is really not much
difference. It makes a difference of about 3% in light intensity...

Remember, it's a square law: a 3% difference in distance turns into about
a 7% difference in light.

(However, Keith is correct to point out that the fourth-root law for
temperature greatly reduces the impact of this.)
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