宇宙 うちゅう背景 はいけい放射 ほうしゃでしょう
uchūhaikeihōshadeshō

Noun
Desu Copula

Expresses probability in a polite manner ("probably…") of 宇宙背景放射

1. Probably cosmic background radiation.

Polite
Presumptive
Conjecture