I'm pretty sure the ancient Chinese could see the colors of at least some of the planets. You don't need a telescope to tell that one celestial object looks red

I'm pretty sure the ancient Chinese could see the colors of at least some of the planets. You don't need a telescope to tell that one celestial object looks redder than another, especially if you have good eyesight and no light pollution. Venus is indeed golden; Jupiter is red-brown like some type of wood; Saturn looks like it's covered in sand (土 can mean dirt as well as rock, and there's a lot of yellow dirt in China); Mars is unmistakably red; and Mercury looks plain white so why not assign it to the only remaining element. Four correct guesses out of five = probably not a coincidence.