A classical reading (ame/ama) of '天' meaning the sky or heaven; used in old Japanese to refer to the sky/heavens.
夜、天（あま）を仰げば満天の星が輝いていた。
At night, when I looked up at the sky (ama), a host of stars was shining.
古歌に『天（あめ）の川』と詠まれる表現がある。
There is an expression in old poems that enshrines 'Ama no gawa' (the Milky Way).