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I've never fully understood why we can still see galaxies that are 10 billion light years away. The age of the universe is calculated to be 13.9 billion years old and we live on a planet that it is roughly 4 billion years old. The universe came into existence 13.9 billion years ago and expanded incredibly quickly but those galaxies that were created in those early years are still visible to us via the amazing Hubble telescope (see the latest from Hubble). Those galaxies would surely have long gone so why can we still see the light from so long ago? How can we see further and further back to the beginning of the universe because surely the light from the moment of the big bang and subsequent eons would have past by us long ago?

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Hi Matt, welcome! I think I understand your question, but before to write an answer it is better to clarify your doubt: is it your question about the "death" of such an old galaxies, or more related to how we can see in the past? –  Py-ser Jun 6 at 8:06
    
More a question of how we can see in the past. I'm trying to understand why the light that left these galaxies is still arriving here on Earth. How did we jump ahead of the light that left those galaxies 10 billion years ago? –  Matt Jun 6 at 8:45
    
Are you aware of the Hubble law? :) based on your answer, I can write a proper answer! –  Py-ser Jun 6 at 8:52
    
I'm thinking of the universe as a big balloon where we all started from the same starting point. So why, if I'm on the circumference of the balloon, can I see a galaxy that is back near where I started? If you explain in terms of balloons I will be fine :) Just kidding. –  Matt Jun 6 at 8:57
    
Py-ser, I am aware of Hubble's law but can't say I understand it fully –  Matt Jun 6 at 9:13

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How can we see further and further back to the beginning of the universe because surely the light from the moment of the big bang and subsequent eons would have past by us long ago?

A simple intuitive way to understand that part of your question: Bigbang happened everywhere, in all of space. As time passes we see more distant parts of the bigbang, or rather, of the microwave background which is the furthest away phenomena we can see. The bigbang as it happened for example 1 billion years ago has passed by us long ago. Today we see the bigbang as it happened 13.8 billion years ago.

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Those galaxies were 10 billion light years away from Earth. So light would take much more time to reach here and that light which is now 10 billion years older can be seen now. Even light from the Sun takes 8 minutes to reach to us. So if somehow sun disappears(very unlikely) we wouldn't know for 8 minutes.

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The deepest we look into the space the further in the past we look. So if we take pictures of galaxies that are 10 billion ly away we see them as they were 10 billion years ago.

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