astronomical unit

US /ˌæs.trəˈnɑː.mɪ.kəl ˈjuː.nɪt/
UK /ˌæs.trəˈnɑː.mɪ.kəl ˈjuː.nɪt/
"astronomical unit" picture
1.

天文单位

a unit of length, roughly the distance from Earth to the Sun, used to express distances within the solar system. It is approximately 150 million kilometers (93 million miles).

:
Mars is about 1.5 astronomical units from the Sun.
火星距离太阳约1.5天文单位
The distance between Earth and the Sun is defined as one astronomical unit.
地球与太阳之间的距离被定义为一天文单位