Where the huge velarium that Nero had stretched across the Colosseum at Rome, that Titan sail of purple on which was represented the starry sky, and Apollo driving a chariot drawn by white, gilt-reined steeds?

横跨罗马斗兽场的巨大天幕，代表空的紫色泰坦帆，阿波罗驾驶由镀的白色骏马牵引的战车在哪里？