What is space made out of? What is the blackness in space?
In: Physics
Space isn’t “made” out of anything; it’s, mostly, where stuff _isn’t_. It’s speckled with stars here and there, a lot of which are clumped into galaxies, and smaller things like comets or asteroids, but most of space is staggeringly empty.
(There’s some cutting-edge theoretical physics hypotheses about how, if you look really REALLY small, much smaller than protons pr neutrons, space is made out of other mathematical stuff. But you need the advanced math to even try to follow those, so in general people work with “space is what’s left when you take all the matter away”, and “space is what lets you have distances between things”.)
Similarly, space, when youi’re not looking directly at a star (including our Sun) or something starlight is reflecting off of (like our Moon, or Jupiter), is dark because … there isn’t any light there. Nothing about space intrinsically glows. And, since the universe is expanding, we don’t run into the Olbers Paradox – most of the directions you look DON’T have a very far-away star exactly in that direction.
(Though if you want to blow your mind a little bit, look up the ‘cosmic microwave background’ – there IS a glow, left over from a while after the Big Bang, but it’s so red-shifted and stretched that human eyes can’t see it, it’s down with microwaves now.)
–Dave, hoping to illuminate
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