I know they help us see further away but I just can’t picture in my head how they work.
Especially when people talk about building bigger to look at galaxies 8 plus billion light years away, surely we’re not looking that far distance wise we’re just catching the light at the telescope so if the light has taken that long and traveled to us surely it’s just as close now as the light from our sun that took 8 minutes so wouldn’t a pair on binoculars work just as well?
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The main issue is that light scatters and space is HUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUGE. So when a photon from a star 8 billion light-years away reaches earth, there aren’t many of its friends around.
Space telescope (or any telescope for that matter) use mirrors to capture that light and reflect it back to a numerical latice for numerisation. The bigger your mirror, the more light you can catch at once. And even with that, they have to look at that region of space for hours and hours to have a clear picture.
On a side note, one benefit of being head of the Space Telescope Science Institue is that you have allocated time on Hubble that you can do whatever you want with. Most of the time it means they can allocate that time to researchers whose observation they think is worth it.
But one former head thought “what if I had Hubble look at that empty region of space where there is nothing for 100 hours ??”
The resulting picture is known as the [Hubble Deep Field](https://en.wikipedia.org/wiki/Hubble_Deep_Field#/media/File:HubbleDeepField.800px.jpg). This was in 1995 and it shook the astronomy world, revealing hundreds and hundreds of extremely young galaxies.
Because the further the object, the older the light and thus the younger the object appears to us (because it was emitted a long time ago).
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