1 Anakin: Ok, even if you could grow enough food on-planet to feed everyone on Coruscant, consider how much energy you'd need.
2 Anakin: Greenhouse lighting, hydroponic reticulation, gas exchange, plus the actual energy consumption of the civilisation.
3 Anakin: That's at least 10¹⁸ watts of waste heat. The surface should be hotter than boiling water, and nearly hot enough to melt lead.
4 Qui-Gon: Anakin, just shut the hell up! It's some weird Jedi magic, okay?

Wow. #386 and #393 have generated more emails than anything else I've done so far in this comic. It seems there are some people out there still clinging desperately to the shreds of anything in Star Wars being even vaguely plausible.

Well, go take it up with Messrs Kelvin and Boltzmann. You can make your social dynamics, city planning, and biology arguments all you like, this is thermodynamics baby. Don't mess with a cartoonist with a Ph.D. in physics. ;-)

(And thank you for everyone who actually did write to me. You gave me beautiful inspiration for this strip.)

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2013-02-02 Rerun commentary: Here we go then...

There are follow-ups to this strip coming up later, which cover many of the questions that this raised in readers' minds at the time. For now, suffice it to say that, under the laws of physics as we know them, it's really, really difficult to make Coruscant work because it should generate so much heat that it would be unlivable.

Star Wars is, however, a space fantasy, so it's perfectly acceptable to just say they have some uber-technology that violates the laws of thermodynamics and be done with it. But that wouldn't be funny.