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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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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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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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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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
??
The ...
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Has any astronomer/physicist used geometry and trigonometry to calculate where the center of the universe is? [duplicate]
Since we are pretty sure that the universe is expanding at a steady and accelerating rate wouldn’t it be possible to simultaneously observe 4 points (galaxies) that are all, as closely as we can tell, ...
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What Parts of the Observable Universe have we Observed?
Everyone talks about how big the observable universe is, all of the complexity, etc... But what parts of the observable universe have we actually seen? What Parts are hidden in relative shadows? Is ...
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Can the gravity of objects entering the observable universe be detected?
As time passes, we will be able to see objects that are further away, as their light eventually reaches us. Since gravity also travels at the speed of light, would we be able to detect when a super ...
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Could the redshift of all incoming photons be explained by a massive ring of distant masses pulling the sources of the photons away?
ChatGPT and wikipedia have informed me that the primary evidence for the theory that the universe is expanding is the fact that photons that arrive to our planet from all directions are being ...
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