Correct pinyin and pronunciation for 太阳 What is the correct pinyin and pronunciation for 太阳?

Most dictionaries put it as: tai4 yang2, but I noticed cc-cedict uses tai4 yang5. There is also a discussion in the change log around colloquial and correct pronunciation. They reference another discussion here which also talks about this, though the references here aren't what I'd call necessarily respected.

So wondering what people's thoughts are here? In additon are there any respected sources for one way vs another for what is the correct pinyin and pronunciation? I'm talking "普通话" specifically.
太阳 Tàiyáng, Sun: pronounced "Tie Yang"


太 Tài：highest; greatest

阳　yáng：sun

You may find some reference yáng as 5th tone (轻声 qīngshēng) because it's easier to pronounce in spoken Chinese. The character 阳 yáng by itself is always 2nd tone.