Nubian sun
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The Nubian sun is used in the saying "clear as the Nubian sun".
Cain uses this term when replying to Apollo's question on whether Cain had been aiming at a Raider: "You didn't, Captain? He was as clear as the Nubian sun to me." This was a lie, as Cain destroys the tankers in order to convince Adama that his plan to attack Gamoray is the best option (TOS: "The Living Legend, Part I").