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 ...

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 ...