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Questions tagged [cosmic-microwave-background]

The cosmic microwave background (CMB) is the electromagnetic radiation in the microwave band which can be observed throughout the whole universe, not connected to any astronomical object. Its spectrum follows a very precise black-body radiation with a temperature of about 2.7 K.

The cosmic microwave background (CMB) is the electromagnetic radiation in the microwave band which can be observed throughout the whole universe, not connected to any astronomical object. Its spectrum follows a very precise black-body radiation with a temperature of about 2.7 K.

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Will the CMB eventually recede outside our observable universe?

As I understand it, some billions of years ago, the universe used to be opaque (edge of the sun - orange colored). Due to the expansion of the universe, photons emitted billions of years ago from billions of light years away are just now reaching us…
nullUser
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Relationship between the cosmic microwave background (CMB) radiation and the visible universe

I know that the cosmic microwave background radiation (CMBR) is the leftover radiation from the Big Bang. Have we been able to make a concrete map of the radiation and the objects in the visible universe? (Something like "this point in the CMBR map…
Jus12
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Do oceans produce the cosmic microwave background?

A guy who has a career in medical physics named Pierre-Marie Robitaille argues in two recently published papers in “Progress in Physics”, that the CMB is not from the big bang but from the oceans. The first paper is entitled WMAP: A Radiological…
user34039
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Could the cosmic microwave background radiation (CMBR) map be used as a backup for GPS navigation?

Using a sextant and a clock you can navigate by measuring the position of the observable stars and comparing them with the known map of the fixed stars. However, if it was cloudy couldn't you theoretically use the CMBR map instead? The cosmic…
Nicholas Lee
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How does the Cosmic Background Microwave work?

I sort of understand it but I am not sure if my understanding is correct. So what I understand of the CMB is: When the universe was created it was very hot, too hot for matter to form. When matter tried to form a photon would smash the electron…
hbblue
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Did Penzias and Wilson use Wein's law (or data based on it) to determine the temperature of CMB?

I'm writing a paper and I used them as an example, but then reconsidered . . . maybe I'm not getting it right! thanks!
Gigi Giles
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Do COBE, WMAP, or Planck data show time-variance of the CMB's anisotropies?

What limits on the time-variance of the CMB do the COBE, WMAP, or Planck data put? In other words, I am looking for a peer-reviewed paper that would answer this question: If I made maps of, say, WMAP Month 1, Month 2, Month 3, … data, would the…
Geremia
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When will PLANCK release all-sky CMB anisotropy measurements?

After hearing so much about PLANCK, people these days are still constraining models with WMAP results. When will PLANCK finally release its much more superior data?
felix
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Future of the cosmic microwave background pattern

Does the comoving size and the observed angular diameter of CMB hot and cold patches change with time in the future?
Rene Kail
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Cosmic Microwave Background Radiation

I'm going through the NRAO Essential Radio Astronomy course and on the section about Cosmic Microwave Background Radiation, it mentions that BB radiation is $T_0 = 2.725 \pm 0.002$ K equating to "frequency of peak brightness" ~ 160 GHz. Could…
George Emsden
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How is temperature of space calculated?

wikipedia says: The CMB has a thermal black body spectrum at a temperature of (T=) 2.72548±0.00057 °K. The spectral radiance dEν/dν peaks at 160.23 GHz Could you explain how is T= 2.72 K obtained? is it an average, is it an integral or what? Is…
user157860
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Will the cosmic microwave background radiation eventually not be microwaves?

I was reading through this answer about the cosmic microwave background radiation, which implied that we receive it as microwaves because it's been shifted to that wavelength by the expanding universe. Did I understand that correctly? If so,…
Telastyn
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Why isn't the cosmic microwave background a solid 3D volume?

This is the cosmic microwave background radiation: It's a Mollweide Projection, which maps the surface of a sphere. Like, this is a map of Earth (also Mollweide Projection): And it only shows the outer surface of Earth. You can't see the…
clickbait
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CMB free containment area for proposed experiments

Could someone please help me? I would like to have a method whereby I can do experiments I have in mind involving a purpose built container of dimensions of at least a foot cubed or it can be larger if easier to built it bigger. My aim is to remove…
user155203
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Derivation of the Hubble constant from the cosmic microwave background

In the paper which presents the results of the Planck measurement (DOI: 10.1051/0004-6361/201321591) the Hubble constant is a derived parameter. How does this derivation work? Moreover, how does the Hubble constant change if we use cold dark matter…
user185188
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