Historically, the astronomical unit was conceived as the average Earth-Sun distance (the average of Earth's aphelion and perihelion), before its modern redefinition in 2012. The astronomical unit is used …

In 1976 the International Astronomical Union (IAU) defined the astronomical unit as the distance from the Sun at which a massless particle in a circular orbit would have a period of one year.

Jan 1, 2025 · One astronomical unit is the approximate mean distance between Earth and the sun. It’s about 93 million miles (150 million km), or 8 light-minutes.

Nov 9, 2024 · The astronomical unit (AU) is a standard unit of measurement roughly equal to the distance between the Sun and Earth. It provides a convenient scale for comparing the distances of …

Nov 25, 2025 · The meaning of ASTRONOMICAL UNIT is a unit of length used in astronomy equal to the mean distance of the earth from the sun or about 93 million miles (150 million kilometers).

The astronomical unit (au) is defined by the IAU as exactly 149,597,870,700 m. It is approximately the average distance between the Earth and the Sun (about 150 billion meters). The IAU has specified …

Nov 7, 2025 · The Astronomical Unit is defined as the mean distance between the Earth and the Sun, which is approximately 93 million miles or 150 million kilometers. This distance is used as a standard …

a unit of measurement of distance in space equal to 149,597,870,700 meters, which was originally based on the average distance between the earth and the sun, or about 93 million miles:

The astronomical unit (abbreviated variously as AU, au, a.u. or ua) is a unit of length roughly equal to the mean distance of the Earth from the Sun. The currently accepted value of the AU is …

ASTRONOMICAL UNIT definition: a unit of length, equal to the mean distance of the earth from the sun: approximately 93 million miles (150 million km). AU See examples of astronomical unit used in a …