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 is the Cosmic Microwave Background at the same distance no matter the direction we look?
I've read from different sources that:
The CMB is visible at a distance of 13.8 billion light years in all
directions from Earth, leading scientists to determine that this is
the true age of the ...
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How did we measure the mass of the universe?
In an wiki article, observable universe, it was mentioned that,
Mass (ordinary matter) 1.5×10^53 kg
I wonder how did we measure the mass of our observable universe?
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Picking two random points in space and drawing a line between them, what is the chance the line intersects anything?
I thought of this question after pondering how most of the observable universe is observable. If we can observe it, then the space between us and that object must have been unoccupied to allow the ...
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Kardashev scale [closed]
Why is becoming a type 3 from a type 2 civilization the hardest?
I have watched many videos on the topic and still can't figure out why?
Also is there a difference in technology between a type 4 and a ...
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Demonstration of scales for the two components (transverse and perpendicular) of Baryonic Acoustic Oscillations (BAO)
I transfer here a post that has not had any answer pn physics exchange, so I am going to delete this latter. Maybe I will have more luckiness here.
In an astrophysics context about BAO (Baryonic ...
user16492
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Intuitive explanation for why the Doppler effect (and red-shift) happens?
I was looking for an intuitive explanation as to why the Doppler effect happens. I haven't found any, but this is what I thought:
-Waves emitted travel at a constant speed
-The source emits a wave
-If ...
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can we calculate the velocity of galaxies at the edge of the observable universe?
I read this post
Does the edge of the Universe travel faster than the speed of light?
but there was no calculation, so I tried it thusly:
The observable universe is 28.5 Gpc (gigaparsecs)
= 28500 ...
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How frequently do Jupiter & Regulus have triple conjunctions?
I am wanting to know if the triple conjunction of Jupiter with Regulus in:
Sep 10, 3 BC
Feb 7, 3 BC &
May 8, 2 BC
with Jupiter later having a conjunction with Venus in Jun 17, 2 BC has happened ...
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How is the gravitational effect of galaxies outside of the visible universe on galaxies within the visible universe currently modeled?
Given currently accepted models of the universe,
How much mass is outside of the visible universe?
What is the gravitational effect of that mass on the visible universe?
The question How strong is ...
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With the expansion of the universe is time also increasing?
With more space being created would there be more time in that new region formed? Is the over all universe increasing in time? This is my first question so go easy on me. PS. Would that also mean that ...
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Various stars moving in a line [duplicate]
I from India saw various stars moving in a line from North-West direction to the South-East direction at 5:27 AM on date 13 february 2020... They all are moving rapidly and can be easily seen from the ...
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Earth as a grain of sand
If Earth was a grain of sand in Buenos Aires
in what point in this observable universe map would be LA be?
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Anecdote of an astronomer looking for correlations in antipodal pairings of stars; what am I remembering?
The question Are the stars distributed in uniform distribution, on the celestial dome, with respect to brightness? brings to mind a different study that I vaguely remember hearing about a while ago, ...
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At what rate is the observable universe expanding?
The observable universe is $4.4 \times 10^{26} m $ in every direction. I told this to my daughter and then added, "And guess what? It's a little bigger today than it was yesterday."
"Wow!"
But by ...
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Could different views of the universe simply be different points in time?
I'm not sure if this is the correct stackexchange site for this question.
I've been reading this article on Vice Motherboard There’s Growing Evidence That the Universe Is Connected by Giant ...
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