Re:Brayton cycle (Score 1)

Actually, I wasn't being a pendantic jackass, I was correcting something that was wrong. Period. Not just a subtle, technical issue that will only appear on an exam; plain wrong.

You can have net heat transfer from an object even with a hotter object nearby via radiation. A radiator will lose heat (via radiation) to space regardless of what it is near. It's ability to absorb/reflect will determine if there is any heat transfer the other way. You can't just simply say what the NET direction will be based on temperature. Only for conduction and convection can you say this...not radiation. What would be the purpose of a shield by the way if you couldn't take advantage of this fact?

Not that you will want to know since you seem to "know" it all ready... the orbital plane of the Earth about the Sun that you are referring to is called the ecliptic. Since I wasn't trying to be pedantic or overly technical, I just said that it was near-equatorial. There is really no need for it to be exactly in the ecliptic for simply for thermal reasons--it would be determined based on other constraints.

As for why drag is an issue here, the radiators needed are huge, as in on the order of 500 m^2. Not that it will slow it down, but it does make attitude control an issue if you try to fly it sideways.