This q stems from a common misconception that we're at the center of the Universe. Let's clear that up: from our position in the Universe, light from the Cosmic Microwave Background (CMB), a relic of the Big Bang, took ~13.8 billion yrs to get to us from all directions. (1/n) 
https://twitter.com/chmn_victor/status/1415380308384489475
A galaxy 5 billion light yrs away is one we see *as it was* 5 billion yrs ago, because light has a finite constant speed in vacuum (space is a VERY nearly a vacuum). Now let's look at the perspective of an intelligent being in that galaxy that's 5 billion light years away. (2/n)
That being, when they look at our galaxy, the Milky Way, will see our galaxy as we can never see it: they see it as it was 5 billion years ago!! And from their perspective, the light from the CMB took 13.8 billion yrs to reach them, from all directions. (3/n)
The most distant galaxy detected, GN-z11, is 13.4 billion ly away. I know, not as cool as "Andromeda"; it's named by the region of the survey it was found in, and z11 stands for the redshift, or *distance*, from us: z=11, or 13.4 billion ly. Just a blob at how far it is! (4/n)
You may think going to this galaxy would bring you really close to the edge of the Universe! However that's not the case: if we could use a wormhole to get to GN-z11, then looking back at the Milky Way, we'd see a blob, and how our galaxy looked 13.4 billion years ago! (5/n)
From GN-z11, light from the CMB took 13.8 billion yrs to get to it, from every direction. There is no center of the Universe! We're not seeing a sphere, we're looking back in time. It's seems spherical because we look out radially in every direction. (6/n)
Because we look out radially, what we map appears a sphere. But the Universe has no center, or edge: the Big Bang did not happen at one point, it happened *everywhere*. Things aren't just moving away from *us*, everything is moving away from *everything* with the expansion. (7/n)
Once you realize space is really space*time*, and looking into space is looking back in time, and the BB happened everywhere and *not* at a point, you'll start seeing there's no center to the Universe, and CMB light took 13.8 billion yrs to reach *anything* in the Universe. (8/8)
One added tweet: it appears that this wasn't exactly the question the person had, but I'm glad it turned into a thread that addresses a common misconception anyway!
And my friends, because I've been asked many times about space not having an edge, there *are* shapes that are still flat spacetime that have no edge and aren't infinite! A torus is one, a cylinder is another.
https://twitter.com/Astropartigirl/status/1415875093897482240?s=19
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