noun
night sky
Refers to the sky at night, often with stars, moon, or darkness. Common in poetic and everyday contexts.
今夜は夜空がとてもきれいだ。
The night sky is very beautiful tonight.
彼は夜空の星を眺めるのが好きだ。
He likes gazing at the stars in the night sky.
星空 specifically means 'starry sky', emphasizing the presence of stars, while 夜空 is the broader 'night sky'.
Compound of 夜 (よ, 'night') and 空 (そら, 'sky'), with rendaku voicing of そら to ぞら.