Distance articles

Are red galaxies further away?

The light arriving at our telescopes from far-off galaxies carries a crucial message about its origin, primarily concern...

Why do astronomers use AU instead of km?

Vast Distances Trying to describe the scale of space using everyday units like kilometers or miles quickly becomes an e...

How far is the Perseus Arm from Earth?

The sheer scale of the Milky Way galaxy often makes precise measurements feel like an abstract exercise, especially when...

What is the astronomical unit AU and how is it used?

The Astronomical Unit, universally abbreviated as AU, serves as a fundamental yardstick for measuring distances within o...

How to tell if a star is close?

Figuring out how far away a star truly is presents one of the greatest measurement challenges in astronomy, largely beca...

How does a star look closer?

The night sky presents an illusion of order, where countless distant suns appear as mere pinpricks of light scattered ac...