What do α and β mean in astronomy? On what basis did you get such a name?

This is the content of the nomenclature of Bayeux. That is, each constellation is sorted by celestial brightness, which is α, β and γ in turn, until 26 Greek letters are used up. However, it must be pointed out that this method has too many counterexamples, and it is longer than the list and shorter than the memory, so no one will use this system to recognize stars for fans. For example, K in Ursa Major, I can find it in a few minutes from the star map or catalog, but let me identify it as the one in the sky. It is estimated that few people can point out the stars after γ.

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