Which unit is equal to the distance from the earth to the sun?
The Astronomical Unit or AU.
See the related question.
The actual distance varies as the earth follows an elliptical orbit around the sun. However, the Astronomical Unit (AU) is defined as a unit of measuring distance in space (much smaller than light years). The AU is the average distance between the earth and the sun and is equal to 149,597,870,700 meters. It is common to refer to it as 150 million Kilometers.
An astronomical unit is the average distance from Earth to the sun, so on average, the Earth is one astronomical unit away from the sun. The earth's orbit around the sun is not a perfect circle, so Earth is not always the exact same distance from the sun. The Earth is usually a little farther or a little closer to the sun, depending on where Earth is in its orbit.
An Astronomical Unit (AU, au, a.u., or ua) is the mean distance from the Earth to the Sun, equal to about 92,960,000 miles. As defined by the International Astronomical Union, an AU is the mean distance from the Earth to the Sun over one Earth Orbit of the Sun. The International Bureau of Weights and Standards recommends the abbreviation UA, but most countries use AU.