Axons
Published in

Axons

The Cosmic Distance Ladder Explained

Distance is something peculiar. It’s very hard to gauge if a celestial object is far away and bright or close and dim. We know that the closest galaxy, Andromeda, is ~2 537 000 light-years away and that Eta Carinae, one of the Milky Way’s brightest blue supergiants, is distanced at ~7 502 light-years. How do we know such distances as we can never actually measure them?

Photo by Mathias Elle on Unsplash

--

--

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store