Aesthetics: Objective or Subjective?

I am going to focus on the philosophy of aesthetics in this post. There is a saying "beauty is in the eye of the beholder" which gives example to beauty being subjective. Is it possible for beauty to be objective? Is the Mass objectively beautiful? Do you consider the Sistine Chapel to be an example of objective beauty? According to Wikipedia, Plato felt that beautiful objects incorporated proportion, harmony, and unity among their parts. How does one distinguish between an object or piece of art being subjectively beautiful versus objectively beautiful?