What is an astronomical unit? Distances in our solar system are vast. So astronomers often don’t speak of the distances to planets, asteroids, comets or spacecraft in terms of miles or kilometers.

One of the stalwart units of astronomy just got a makeover. The International Astronomical Union, the authority on astronomical constants, has voted unanimously to redefine the astronomical unit, the ...

Click anywhere on this site, and you’ll likely run into a measurement in terms of light-years, solar masses, astronomical units, or arcminutes. These units are unique to astronomy, and all can be ...

Without fanfare, astronomers have redefined one of the most important distances in the Solar System. The astronomical unit (au) — the rough distance from the Earth to the Sun — has been transformed ...

The International Astronomical Union drops the mic. How far away from Earth is the sun? Not just, you know, very, very far, but in terms of an actual, measurable distance? When you're calculating, how ...

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 confusing calculation (“the radius of an unperturbed ...

One of the stalwart units of astronomy just got a makeover. The International Astronomical Union, the authority on astronomical constants, has voted unanimously to redefine the astronomical unit, the ...