SAMU,

Okay, it's clear to me that you have your theory and you're in love with it. Nobody's going to convince you you're wrong, and you're not going to convince anybody here that you're right.

But I'm enough of a masochist to take one more shot, even at the risk of being called "lame".

You claim the moon's surface is much brighter than fresh asphalt. Assume for a moment that this were true -- that the moon was a good reflector, and nearly white.

If that were the case, then the surface of the full moon would look nearly as bright as the disc of the sun! A moonlit night would have at least a dark-blue sky, and the moon would be too bright to look at directly. (No, it wouldn't be quite as bright as the sun, because some of the infalling light would reflect away in other directions. My point it that the moon would be far, far brighter than it is.)

But really, that's a side issue.

The main question is, if an Apollo spacecraft lost nearly all electrical power, would the cabin warm up or cool down?

Your own evidence shows that the designers were coping with a major heat buildup problem(under normal conditions) -- so much so that they had to provide lots of active cooling. The issue becomes, what is the source of that heat? We know of three possibilities: solar radiation, the astronauts' metabolisms, and the onboard electronic equipment. Which was the main contributor?

If it was the electronics, your claim falls apart, because all the CM systems were shut down, and the LM systems were running at a minimum level (and still being actively cooled, I might add -- you can't use a computer as a space heater without causing it to fail in both capacities).

OK, so how do we determine where the heat came from? We can discount the astronauts themselves. Their body heat wasn't nearly enough to require all that refrigeration. So was it the sun, or the electronics? I say that the presence of the radiators proves that it was the latter.

Remember, weight is critical on any space mission, and the lunar missions especially so. Refrigeration systems are heavy, and the more heat they have to dissipate, the heavier they get. So a spacecraft designer is going to do everything in his power to reduce the amount of heat that has to be removed.

But an electrical or electronic system can only get so efficient (given a particular era's technology). This was in the infancy of mircocircuits, and even a modern computer puts out quite a bit of heat. So for a given roster of electrical gear, there would be an irreducible heat budget.

But solar gain is something you can do something about, and it's not only easy to do but costs nothing in weight. That's to make the spacecraft as highly reflective as possible, reducing the solar gain so as to make the cooling system's job that much easier. A shiny surface doesn't weigh any more than a dark one -- maybe less.

In summary:
- Apollo had active cooling systems.
- So, Apollo had to get rid of excess heat.
- So, Apollo would have been designed to absorb as little solar heat as possible.
- So, since it still needed radiators even though it was reflective, the heat source was something else.
- So, the heat source was internal electrical equipment.
- The electrical equipment was nearly all turned off after the explosion on 13.
- Therefore, the cabin got cold.

I've said all I care to say on this topic. Have a nice, paranoia-filled life, SAMU.