Thanks to the Webb infrared telescope we do see galaxies now over 30 billion light years away, and we “see” the Cosmic Microwave Background surface now 46.5 billion light years away. We will never see either of these as they are today, because they are (well) being the Hubble distance (14.5 billion light years) and receding from us faster than the speed of light. We see them both only as they were in the very early universe and much closer,
They were even then moving away from us at speeds higher than that of light and indeed faster (for the CMB 60 times the speed of light) than their recession rate today. Here’s why (light path shown for the CMB):
The light that we see, initially 60 times the speed of light originally moved rapidly away from where we are now, and only as the expansion of the universe slowed did the receding light (red line) stop at what was then the Hubble distance 5.7+ billion light years away, and as the Hubble distance (now 14.5 billion light years) continued to grow, move slowly (at first) toward where we are now. The speed of the CMB light, on the green line approach to us now, reaches the local speed of light only asymptotically as it reaches earth.
All deep space light reaching us on earth from s given direction follows the same time/distance curve:
The CMB radiation is the only light going the full distance, beginning only 42 or so million light years away. 380,000 years into the Big Bang, reaching earth after a 13.757 billion year journey out to an ancient Hubble distance, and to earth only now.
Meanwhile, the material that we see from 14 or so million light years so long ago has moved out today to 46.5 billion light years, the radius of the observable universe.
We will never see it as it is today.
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