the room is exactly the diameter of Jupiter to my memory

the rest gradually gets consumed as the city expands; there's that one part where a guy explains to killy how the room they're in is as large as saturn or jupiter (I forgot which one)

i think the deal is that "the city" is so so big that it doesnt even really matter anymore whats outside of it. the world is big enough, imagine that this is the size of the whole solar system

What ever happened to the rest of space in Blame!

is that from blame?

Yep. My thoughts exactly.