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.

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 ...

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 ...

The sun still shines as bright, but according to the International Astronomical Union (IAU), its precise distance from us has just changed. At a recent meeting of the IAU in Beijing, China, members ...

Appearances aside, the stars are not eternal and the planets do not move with clockwork precision. For these reasons, one astronomer is proposing that his colleagues ditch the astronomical unit, or AU ...

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 transit of Venus was the preferred method for assessing the length of an astronomical until for a long time (Jan Herold) During a meeting of the International Astronomical Union (IAU) held last ...

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 ...