The astronomical unit for length is described as the “mean” distance (average of aphelionPoint farthest from the sun in a body's elliptical orbit. Click on Term to Read More and perihelion distances) between the Earth and the SunOur parent star. The structure of Sun's interior is the result of the hydrostatic equilibrium between gravity and the pressure of the gas. The interior consists of three shells: the core, radiative region, and convective region. Image source: http://eclipse99.nasa.gov/pages/SunActiv.html. The core is the hot, dense central region in which the. Though most references state the value for 1 AU to be approximately 150 million kilometers, the currently accepted precise value for the AU is 149,597,870.66 km.
The time required for light to travel from the sun to the Earth is approximately 8 minutes and 20 seconds.
Symbol: au, ua, or AU