Mistake in sentence: The colour of a star depends on the heat, and how much...

Please help me to find what’s the mistake in this following sentence:
The colour of a star depends on the heat, and how much energy it produces
Really, I find this sentence nothing wrong

Quite frankly, neither do I.
Maybe someone else will spot the blemish.

(on the second thought, I think it should be like this: The color of a star depends on the heat and energy it produces, though I’m not completely sure)