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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What is the rarest stable element in the universe? [closed]
I am making a hard sci-fi game with a focus on realism, in this game there is a need for a hard element to base money off of. Similar to how gold is used on earth.
I know there are lots of elements ...
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where are we in the universe as compared to the observable universe? [duplicate]
For distant galaxies to be accelerating away at equal speed in every direction, Earth would have to be at the centre of the universe. Since it is not, some region of the distant galaxies should appear ...
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Conditions in the Early Universe
I am interested in how the large-scale properties of the Universe change over time.
Does anyone know a trusted website which gives the temperature, density and radius (distance to the particle horizon)...
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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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Other Hubble spheres with no Lorentz symmetry?
Perhaps this may be a stupid question but anyways here it goes...
If the Lorentz symmetry is not global but rather local, wouldn't that mean that is possible that other Hubble spheres outside our ...
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When Only 50% percent of the sky will be filled with stars?
Answers to Approximately what percent of the sky has nothing in it? seem to suggest that with enough depth, we will finally hit something hence the sky is basically 100% full for any given resolution. ...
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Approximately what percent of the sky has nothing in it?
From my persepective here on Earth, the sky seems to look like a few large-ish things and a bunch of tiny things. Hubble teaches us that even the apparent void between the tiny things has many very ...
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Would an observer standing at the edge of the "observable universe" perceive the expansion of space-time?
I got this bizarre idea in my mind, after reading SCP-3321
There, as a person gets teleported through a wormhole, ends up at the edge of the Observable Universe, 46 billion light-years away from Earth....
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Are there any binary red supergiants?
I wonder if we ever have identified or observed a pair of binary stars (red supergiants). And I also wonder what would happen if they exploded, (theoretically) as we haven’t observed it. Also, would ...
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How do we know universe is expanding and not light slowing down? [duplicate]
We tend to take some things for granted, for example the light of speed is constant, but what if it isn't? How can we know that light is not slowing down at great distances for example, or that light ...
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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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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 much larger will the "observable by us" universe be when JWST becomes operational?
Right now, using all our various current means of observing, we can "see" a sphere of X diameter around us. Webb will increase that to Y diameter. So our observable volume will increase by ...
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Is the solar system the only survivor of cosmic evolution? [closed]
A question has entered my mind, we know that all the phenomena in the universe are several thousand light years away from us, so the light we see from them is related to the past few years, now my ...
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How is observable matter distributed in the universe?
The observable matter in the universe is distributed and arranged into various structures, including black holes, stars, nebulae, and the much more diffuse regions of the inter-stellar and inter-...
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