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If JWST can look into past then why it cannot find how the sun formed 4.603 billion years back?

I heard that JWST will process infrared light waves to make them more clear to the human eye but not it will directly look at the stars like our eyes looking at things now.

If that is the case then it also would have processed light waves produced by sun 4.603 billion years back right?

Similarly I have another question about future also.

If JWST can look into past then JWST in a future planet also might be looking at our sun now then it would also have generated light i.e. JWST on our earth might be looking at future stars also right?

If light travels in all directions then JWST on our earth might be looking at future stars also right?

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    $\begingroup$ The JWST is not 4.603 billion light-years from the Sun. $\endgroup$
    – notovny
    Commented Jul 21, 2022 at 16:22
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    $\begingroup$ "JWST on our earth might be looking at future stars" What do you mean? Are you implying that light can travel backwards in time, from the future to the past? $\endgroup$
    – PM 2Ring
    Commented Jul 21, 2022 at 17:47
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    $\begingroup$ Re, "If JWST can look into past..." But it can't really do that. JWST can only look into the past in the same sense that you look into the past when you look at old photographs. The physical reality when you look at those photographs is that you are looking at chemical stains on a piece of paper that you're holding in front of your face in the present moment. The physical reality for JWST is that it's looking at ancient light rays that are captured by its mirror in the present moment. $\endgroup$
    – Solomon Slow
    Commented Jul 21, 2022 at 18:50
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    $\begingroup$ I've just arrived in this community. Is there a habit here of downvoting questions from people who may not have made correct assumptions when formulating it? Is that to discourage the person from asking other questions? Because it certainly could. $\endgroup$
    – Rondo
    Commented Jul 22, 2022 at 3:11
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    $\begingroup$ @Rondo downvotes are used as a signal of quality to signpost others users about a question, not to punish/cast judgement on a user (questions are downvoted, not users). The tooltip for downvotes says 'does not show any research effort' which I guess might the reason for downvoting, since any trivial amount of research about the speed of light and telescopes would have answered this question, i.e. the second google hit for a search returned this which would have explained it. $\endgroup$
    – user438383
    Commented Jul 22, 2022 at 7:36

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The James Webb Space Telescope has the potential to observe things that occurred thirteen billion years ago, because those objects were at sufficient distance at that time that the light they emitted took thirteen billion years to get to where the telescope is now.

Any direct sunlight that reaches the JWST would have emerged from the sun roughly 500 seconds prior to its arrival at the telescope. Any remaining photons emitted by the sun billions of years ago are currently billions of light-years from the Sun, and getting further distant.

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  • $\begingroup$ I remember reading some thought experiments in which under certain assumptions (like bounded vs unbounded Universe model or somesuchthing), there might be a way for light from our sun to be lensed back to us: I think most of those assumptions have been disproven but I can't recall the details now. I think in the end, and if it were possible at all, the idea that we would be in a place to see our own 'reflection' is extremely unlikely unless the model of the universe was very simple with a lot of symmetries at large scales, etc. $\endgroup$
    – Rondo
    Commented Jul 22, 2022 at 3:23
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    $\begingroup$ @Rondo A black hole BH can easily deflect light back to its source. But the odds of finding a black hole (or a series of them) that lets us see our galaxy or solar system are extremely small. Please see astronomy.stackexchange.com/a/49874/16685 $\endgroup$
    – PM 2Ring
    Commented Jul 22, 2022 at 16:16

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