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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Would we know if the universe was rotating?
I was wondering what we would observe if the universe had a small rotation. My conclusion was that galaxies on the equatorial plane of the universe would be slightly more redshifted than galaxies than ...
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How many individual extrasolar "shiny" objects has humanity identified?
Sorry, if this is a 'stupid' question of a non-expert, but this question came recently up in family discussion of mine and I couldn't give a satisfactory answer:
I know we have good (?) estimates of ...
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Why no Big Bang are happening now?
Why we are not able to see any Big Bang now? There is a possibility, I think.
Is it that Universe is so large that the probability of it's happening in the observable universe is almost zero, or is ...
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Does "Angular Diameter Turnaround Point" solve the Great Wall Problem?
According to Wikipedia,
The Hercules–Corona Borealis Great Wall is the largest known structure in the observable universe, measuring approximately 10 billion light-years in length.
But since it's ...
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How can the universe be 13 billion years old, but objects are seen farther away than that? [duplicate]
I keep running into this paradox, and the answers I get seem to be the same and not satisfying.
Most sites say the universe is about 13 billion years old, but we can see objects farther away, like 50 ...
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Is there any way to detect the three-dimensional distribution of baryonic gas in our Universe?
As the title suggests, can the current observational techniques detect the 3D large-scale distribution of the baryonic gas, rather than just the gas within groups or clusters?
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Is our universe flat?
I heard our universe is flat. Then one question is puzzling in my mind. If our universe is really flat, why we measure distance from any point across in a spherical way. In other words, why we say, ...
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Is there anything currently 46 billion light years away from Earth that we can see?
If the oldest galaxy ever discovered, i.e GLASS-z13, is at a present proper distance of around 33 billion ly from Earth, why then do we define the observable universe to have a radius of around 46 ...
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Was the Big Bang an event within a preexisting Universe, or did it mark the beginning of the entire Universe, beyond just the observable Universe?
Could it be that the Universe is truly infinite, and the Big Bang was merely a singular, specific event that resulted in the birth of a 'bubble,' i.e. what we perceive as 'the observable universe'? ...
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As of now how much larger is our practically observable universe compared to just prior to JWST becoming operational
On April 2 2022 I asked for estimates of expected results. How much larger will the "observable by us" universe be when JWST becomes operational?.
As of Jan 27 2024 with JWST operational for ...
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Size of the whole universe if it were spherical
Suppose the universe is spherical and its density ratio is
$\Omega \leq 1.00125$
$\Omega = 1.00125$ is approximately the maximum possible value of the density ratio according to the Planck Mission ...
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Formula for rate of expansion of the universe vs distance?
How does the distance $r$ scale with the expansion of the universe?For example if $r_{o}$ is the distance between us and a galaxy and $V(r_{o})$ is the rate of expansion of the universe at that ...
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How can telescopes see anything at all?
I'm impressed that we have any telescope imagery at all. Take the images we have from the "Pillars of Creation".
The Pillars of Creation is in the Eagle Nebula, some 7,000 light-years away ...
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Is the universe still considered "finite but unbounded"?
The BBC reports in Alien life in Universe: Scientists say finding it is 'only a matter of time' that Scotland's Astronomer Royal, Catherine Heymans, has said
We live in an infinite Universe, with ...
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What natural astronomical object is rare on a Hubble volume scale?
There are some milestone objects on different scales of the universe.
The star is a notable feature on a solar system scale
The supermassive black hole is a feature on a scale of a galaxy
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The ...
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