観かん測そく可か能のうな宇う宙ちゅう

expression, noun

observable universe

Astronomy term for the spherical region of the universe that can be observed from Earth, limited by the speed of light and the age of the universe.

• 観かん測そく可か能のうな宇う宙ちゅうの直ちょっ径けいは約やく930きゅうひゃくさんじゅう億おく光こう年ねんと推すい定ていされている。

  The diameter of the observable universe is estimated to be about 93 billion light-years.