An astronomical unit (AU) is exactly 149,597,870,700 meters (92,955,807 miles or 149,597,871 kilometers), according to the International Astronomical Union (IAU). This is roughly the average ...

If you guessed the astronomical unit, you are correct. The au — the rough distance between the Earth and the Sun — was previously determined by a ...

But even something as big as an astronomical unit isn’t enough for the hugeness of space. The nearest star to us, other than the Sun, is Proxima Centauri, likely part of the Alpha Centauri system.

Next time a 5-year-old asks you how far the sun is, know you have the unanimous support of the International Astronomical Union (IAU) in answering clearly and confidently: 149,597,870,700 meters ...

Scientists still define astronomical time in years, ... The International Astronomical Union, based in Paris, decided in 1976 to define the astronomical unit of time as one day of 86,400 seconds.

The astronomical unit (au) — the rough distance from the Earth to the Sun — has been transformed from a confusing calculation into a single number. The new standard, ...

One AU is roughly the average distance between the Sun and the Earth, or 149,597,870.691 kilometres. But its formal definition by the International Astronomical Union (IAU) is rather more complicated.