AcidShAwk t1_itnc0gz wrote on October 24, 2022 at 10:20 PM

Reply to comment by RedSteadEd in Webb reveals unprecedented glimpse of merging galaxies. Because light takes time to travel to us, when we look at objects like this one in the very distant regions of the universe, we're seeing light that was emitted about 11.5 billion years ago by Wagamaga

> I'm not sure if I understand this... yes, we have pictures facing the opposite way in the universe that also have light that originate from 11.5b years away. Or, are you asking what it would look like if, 11.5b years ago, someone in that galaxy took a picture of us?

Take a volume of space, and position a spherical point within that space.. now draw a vector away from the sphere from 6 equal-distant positions on the spheres surface.

Take a picture from each vector origin in the same direction as the vector.

That would give you 6 distinct images from every possible direction away from the sphere.

Do we have images of 11.5b years ago from every single direction away from the earth?

[deleted] t1_itqwr2l wrote on October 25, 2022 at 5:24 PM

[removed]

pittaxx t1_itu6ly7 wrote on October 26, 2022 at 10:23 AM

Still no idea what you are talking about.

Humanity had the capability to take pictures for so little time that on the scale of the universe earth is a point that doesn't move.

And the 11.5b years only apply to the objects really far away. How far into the objects pay we see is directly proportional to how far away the object is. The closest star is only 4 light years away, so we see it as it was 4 years ago. (Estimated) 13.3b years for the oldest point of light we found so far.

If you want to think in vectors, you have to add a fourth dimension - time. You draw a vector from earth, but you extend it over time, and for each 1 light-year of length you are turning the galaxy simulation back one year. Only the objects that intersect the tip of the vector are visible to us, nothing else is.

Now repeat that with infinite number of vectors and you have an expanding bubble. Everything on the surface of that bubble is equally old, but since objects don't move faster than light, we only have one snapshot of them.