okay so. does anybody remember this creepy image? and yes, it's real, by the way.
this is barnard 68, a dark nebula that does not allow light to pass through. it's quite close to us too, and so dense that the stars behind it can't be observed from earth. it's just a molecular cloud, though! looks like a tear in the fabric of existence itself, but it's just a very big dark blob of gas floating in space. barnard 68 is often confused with the boötes void, which is also referred to as "the great nothing".
what's that, you say? oh, well... it's a region in space about 330 million light years wide. this is about 0.27% of the width of the entire observable universe. an area this large is expected to have around 2000 galaxies, but this one only has 60. everything else is just... dead, empty space.
okay, what if i told you that we actually are within a void ourselves? it's called the kbc void. another name is uhh.. local hole. anyways. it's theoretically the largest void we know of, about 2 billion light years across. it's extremely speculative, but it might account for the hubble tension; that is, shit seems to be flying away from us faster than it should be.
some people claim other things cause the discrepancy in our observations of the hubble constant, some debate whether it's consistent with our current cosmological model at all. it isn't completely accepted by the astrophysics community, but it's not a preposterous claim to make either. i personally think it's cool.
maybe shit does fly away faster from us because we live in a local hole. the rest of the universe is an intergalactic party, and we're not invited.
