AU

An astronomical unit (AU) is a measurement used to describe distances within our solar system, roughly equal to the average distance between Earth and the Sun. It’s approximately 93 million miles (150 million kilometers). The AU provides a convenient way to compare distances between planets and other objects, making space measurements easier to understand. For example, Mars is about 1.5 AU from the Sun, meaning it’s 1.5 times farther from the Sun than Earth is. This unit mainly applies to solar system scales and helps astronomers communicate distances clearly.