Questions tagged [observable-universe]
Questions regarding the region of space containing all the objects that we can detect using any method of observation.
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Why are all quasars so far away?
Why are all quasars so far away?
If the universe is homogeneous, we should expect to have a homogeneous distribution of quasars, but all of then seem to be far away from Earth. Why is that?
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Why can't we see distant galaxies with the naked eye?
If light keeps travelling in a straight line, why can't we see distant galaxies with the naked eye? Surely if you stared long enough, the light from them would eventually hit your eye? I apologize if ...
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How can I see a nebula?
I've recently been seeing a bunch of pictures of nebulae and I'm just fascinated by their beauty and complexity. Is there any kind of telescope that would make it possible to view it from here on ...
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Does CIBER Experiment from Caltech suggest that there can be lots of stars which are not in any galaxy?
My question is about the implications of the observations recently made by the Cosmic Infrared Background Experiment, or CIBER, from Caltech. I've read at Caltech web site:
"The total light ...
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Red shifting galaxies
I am an amateur astronomer please correct if any of my understandings are wrong. We all know that from the Hubble's ultra deep field image the most distant galaxies which were created shortly after ...
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Objects entering or leaving the observable universe
Have there been any observations of objects entering or leaving the observable universe?
When looking at the physical limit of observing something like this I will to assume that the "object" would ...
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What is the radius of observable universe- 46 billion LY or 200 yottameters?
I have found two answers for the radius of the observable universe. Wikipedia (and other places, including this site) say approximately 46 billion LY. I am researching this to study for the National ...
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Why aren't the farthest objects close to each other?
The last years we find some objects like this : MACS0647-JD which are more than 13 billion light-years away from us.
This means that the picture we get was created only some million years after the ...
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Can we see the Big Bang happen if we look far enough?
The observable universe is constantly expanding as more light from the Big Bang reaches us. This light has been travelling for billions of years, so we are looking at the universe as it was a few ...
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Infinite universe? How? [duplicate]
So it seems the overall thought is that the universe is infinite. I don't get how.
Most depictions I read mention something to the effect of "at 1^-20 seconds the universe was the size of _". (...
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How many new galaxies enter the observable universe each day/year/decade?
Each day light has more time to reach our eyes from distant galaxies. In one day, light travels 2.59×10^10 km.
So our observable universe (assuming my simple math skills apply here and there isn't ...
crclayton