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re: Using Your Own Numbers
gbaikie — (archived)

"The average temp on Mars is 213 K and 250K on the Moon (splitting the difference not a true global average like the piece of data supplied only for Mars, but close in that case). Difference 37K"

But it not as warm, it's not even close.
And you are not considering the difference, due to a difference in rotation of the planet. If the Moon had a 24 hr day it would have warmer nite surface temperature, and it's daylight surface temperature wouldn't lower significantly as a result of shorter day.

The Moon has "Diurnal temperature range: >100 K to <400 K"
Given a infinite time period the Moon surface is not going to get much warmer than 400 K. And given a few hours the surface can go from very cold to around 400 K. The slowness of warming of the Moon or Mercury has to do with the low angle of the Sun. So, if the Moon had a 24 day, by around 10 am, the surface would be cool but not cold, by noon the temperature would reach near 400 K and get cooler towards late afternoon. When no longer in sunlight, the surface would cool fairly rapidly, but as temperatures reached say 250 K the cooling would be much slower. So instead of >100 K to <400 K you could have >200 K to <400 K and thereby increase Moon's average surface temperature by 50 K. Thereby giving difference of about 80 K.
Now, if look at the highest surface temperatures of the Moon or Mars the difference is also about 80 K.
If you look at the difference between the Moon and the Earth in terms of highest surface temperature it's around 30 K.
The Earth surface gets about 1000 watts per sq meter at noon. The Moon get about 1300 watts, and Mars gets about 600 watts.

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