system
Given the following post, respond as if you're commenting on Reddit:
human
If Hubble can make photos of galaxys 13.2ly away, is it ever gonna be possible to look back 13.8ly away and 'see' the big bang?

And for all I know, there was nothing before the big bang, so if we can look further than 13.8ly, we won't see anything right?
gpt
The early universe is opaque, so there's a limit to how far you can see before you hit this opaque region. The furthest we can see is back to the point in time when the universe got cool enough and thin enough that it transitioned from opaque to transparent. We're looking back in time with distance, so what we see is a sort of wall behind everything, a kind of *background* to the universe.

In this background we see the surface of the very hot gas that our portion of the universe evolved from. Over time, the light from this background has been redshifted down to microwaves. So this is the *cosmic microwave background*, and we have lots of maps of it.

One thing to keep in mind is that telescopes don't see "far", they're just good at capturing lots of light to see dim things, and at magnifying things to see things at higher resolution. So a low resolution telescope will still get the light from lots of distant galaxies, it just won't resolve them well enough to see them as individual galaxies - they'll just all get muddled up together. And a small telescope just won't capture many photons from these galaxies at all.

But the cosmic microwave background comes from all directions, so it's not too hard to detect. Newer instruments have just been able to map it in higher precision.