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 point of space telescopes isn’t that they can see objectively further, it’s that they can see clearer without that pesky atmosphere blocking large swathes of wavelengths (infrared and xray/gamma are particularly bad) and distorting everything.
That’s important for “ultra far” views because the light from the furthest objects has been stretched out into infrared.
So a better comparison than telescope vs. binoculars is fog vs. no fog at the worst end, or trying to observe something through binoculars through heat shimmer and without at best. The latter can be amd is regularly done, but it’s just better without it. The former just doesn’t have a solution aside from “go to space”.
The main thing is that the atmosphere does some things to light that we would like to avoid. To a powerful telescope, looking out through the atmosphere is like us trying to look at the ceiling from the bottom of a pool of water; it gets all fuzzy and distorted. On top of that, light from the ground can bounce off the atmosphere back down, and go into the telescope. Putting the telescope outside the atmosphere lets us avoid those problems.
1. Earth’s air causes the scattering of light from space – hard to get perfect pictures – especially if the amount of light you’re capturing is very little in the first place.
2. Binoculars have two lenses – one at the end and one near your eye – each one messing with the light a little bit. Space telescopes are reflecting telescopes (thanks Isaac Newton for the idea!). These are FAR superior – they reflect light better than lenses magnify light. The reflection gets captured in an amazing digital camera with almost no distortion and we get the pictures.
3. Space telescopes are MASSIVE. The giant mirrors can gather up more waves of light than a little set of binoculars can.
Add these three things up and they amount to a GIGANTIC difference in image quality from a reflecting space telescope and regular ol’ binoculars.
Telescopes just collect and focus light from distant objects. When objects emit light, that light spreads out as it travels further away from the object. That, coupled with the fact that objects appear smaller the farther away they are, means we can’t see a lot of distant objects with our naked eye. Telescopes use lenses and/or mirrors to collect more light than we can see with our eyes and to make the objects appear larger so we can see them.
I have no idea what you’re saying in that paragraph because it’s one giant run-on sentence and I can’t decipher it. If you’d like to try and fix that, I’ll be happy to address what you said there.
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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