Imagine taking the distance that light travels in an entire year. Now turn that distance into a cube, each side one light-year across. How much "stuff" would be in there? And how empty would it be? It all depends on where you put your massive cube.
Everything in this image is so far away that it defies our comprehension. And yet we're also looking at two vastly different scales here, as stars from well within our own galaxy share space with a far distant spiral galaxy.
Apparently our radio broadcasts can be listened to in a "space bubble" 200 light years in diameter. That's huge! But when you compare it to the rest of the Milky Way, um, not really. So just know when you're hoping an E.T. will find you through your radio broadcasts, he has to be within that bubble to hear you. God,…
