Cosmic Microwave Background Explained 

LMAOOO

As the saying goes, we are stardust!

The fact that we are cognizant of this could mean that we are more imo

@@jan_sim1969 true. If someone would be 70million lightyears away and has a really really strong telescope he would still see dinosaurs wandering earth and would not know we even existed.

@@mercuryfalconog maybe.. or would be becasue the zoom in they would see it as is… the lens makes distance closer so would it not bring time with that . Only if u look at the planet from a distance in view would it appear in the past cuz ur seeing the light from that long ago But a lens would make it zoom in seeing the planet as is in time… :)

The answer is yes. Orange (the colour) has the name orange *because* of Oranges (the fruit).

Chris Vitullo QUESTION: Which one came first, the fruit or the color? ANSWER: Yes ???....genius -.-

lgmatias the color obviously...

lgmatias Grue came first.

i made that joke before i watched the video and now i feel like an idiot

+zmunk Nonsense, thump another attaboy on. Now if you said 'Oh, you mean space used to be a toaster' that would have been idiotic.

hmmmm what if space was shaped as a toaster.... how interesting would it be to move around in it?

@@agimasoschandir so we can't toast our bagles in this cosmic microwave?

@@curtishollerback6707 I like the crispiness of a toaster. Using a cosmic microwave would leave it a bit soggy I suspect

what if a galaxy filament is just a single neuron in a guy who got hist toast stuck in the toaster? (hits bong)

addition - we live in a microwave/toaster of an alien then where we live Slices ?

Heard some grapevine the world is a sitting on an elephants nose. LOL.

Or a toaster simulation.

An exponentially expanding microwave toaster*

+LukeDude759 It's sign language with Italian accent !

He's not actually doing sign language though XDDD

***** It was a joke, I just played into it :P

+Reydriel duhh

+LukeDude759 3:56 Grabbing 3:58 Rubbing 3:59 Flapping 4:01 Holding 4:04 Tapping? 4:06 Pouring 4:09 Squeezing. I see what he's imagining.

+Lucas Gearheard Its not the attitude. It just is never aliens. Or our future selves. Or supernatural beings. Or cosmic pixies.

+Agimaso Schandir man stfu 😂

I'm not saying it's not aliens. But it's not aliens.

Lucas Gearheard sounds like something an alien would say

You can't just outright deny the evidence, the x files exist!

+Tobey Plug no

+Tobey Plug I had to stop watching with sound because of a headache I was getting from it.

+Tobey Plug It's the C-Hum-B

I thought my computer fan was damaged and buzzing. The hum doesn't make a good illustration for the CMB, because it is four isolated tones, approximately, 206, 620, 1035, 1477 hertz, which I succeeded removing with an equalizer with minimum hollowness to the voice, whereas black body radiation is broadband.

+Tobey Plug yeah noticed it too i really thought my headset was broken

puncheex2 Yep. Precisely.

+puncheex2 Question: Has the universe ever turned white?

White is a concept, not a color. Red, green and blue are colors - I can give you an EM radiation frequency for each of them. White is the combination of all the colors naturally occurring in the proportions that the sun has provided them for the past 200,000 years or so, (say the sum total of a 3000 degree black body) as modified by our atmosphere. So, yeah, at some point the universe (as seen from Earth) no doubt radiated at that temperature as it wound down from 10 billion to its current 2.7 degrees, and humans would have seen it as white. It would have been the equivalent to being in the center of a 3000 degree oven.

***** The land of the Whos could use a little Warming. And Max understands, cringeingly.

if our eyes didnt melt,,,, would it look white or black during the first ever second of the universe, since gamma is not visible?

Beam me up scottie I can't get it

Lol dude sounds normal like this

Lol

U must b religiois

Ikmal Axl yay!!!! Yes !!!! Someone, finally.

@@seashley8931 uhh did i do somethin wrong?

CMB's have extremely weak intensity.

There is actually a very very very small bit of static we receive from the CMB, but its only visible on either super sensitive radios or old rabbit ear antenna tvs

Most is a good job. In that blackbody curve for the toaster the horizontal axis is calibration is way off. The toaster's peak wavelength is much much shorter than 3000 mm.

+electrocat1 Orange is the new black is on netflix.

BoredThatsWhy cool!

Yes please! xD

askdubi What problem? You make gravity just being there brah! Just gotta get something bigger! But then you would be on a planet. But isn't a planet just a really big spaceship? They just don't steer very well.

Obama Morton true, but let's say you want to create an environment with artificial gravity. like a room where you can lower the gravity or a space station that holds a steady 1g.

askdubi I feel ya bro. It would be pretty hard. If mass is related to gravity then making artificial gravity would use a lot of energy.

askdubi not sure that is really a problem and more of a fantasy.

Same lol

***** lol. worth it.

someone had to make this joke before me

Julian Lö adjust the playback speed it helps

I am undergoing the same process in reverse now. :P

Yes he talks very fast, but he also slurs his words a little and doesn't enunciate as clearly as you'd typically want a communicator/educator to.

idiot, pause it, go back and forward again.

Carlos Mariano Tosza bro chill lol, dont have to insult him

Albert Mendoza Yes they would

Yep! It'll take a lot of expanding, but absolutely, they'll drop to radio waves eventually.

So wouldnt we see different wavelengths across space? If we look billions of lightyears into space, we'll be looking billions of years into the past, being as all waves take time to travel. So wouldnt we be seeing shorter wavelengths further into space rather than it all being the same?

Ethan Grazier Nope. The further we look through space, the longer/more redshifted then wavelengths will be. When light travels further and further throughout space, the expansion of the universe stretches the wavelength more and more.

@@user-ys3xr9bl7f but still, doesnt that mean those wavelengths would be hitting us at at different parts in time depneding on how far away they are from us? Just like light from stars hit us from different points of time due to how long it takes to get to us. Recently been trying to learn a lot more about the expansion/big bang theory, hence the questions.

Google it?

Basically, if I understand your question, it means the heat signature, the way the radiation is spread out over the whole universe. Maybe put a timestamp next time you want clarification of something from a video? It often really helps, especially when someone can go to that part and listen to the context of what you are wanting to know about. I hope this clears it up, at least somewhat, for you. Like I said, a timestamp would have helped, because I don't recall that specific phrase being used, and I really don't want to watch this all over again, just to try to listen for those specific words.

(5 years later still responding lol) I think that is the coolest thing. Obviously there never was nothing, because then there wouldn't be anything, as matter cannot be created nor destroyed (unless laws didn't apply to space at this point? Which might be possible...) So, therefor, there had to just be at least something, but apparently, there was nothing but empty space. It's also said that the universe was very cold, but if it was true empty space, how is it cold?? Doesn't something have to be physical to be cold? So how could an empty space be cold??? It's all really confusing, but really cool, too.

​@@memehivefive9852 ..... Five years later and you just threw me back into that existential crisis 😂😂😂😂

i like red

@@Dannyisgreatful robloxs logo is red so u like roblox

jamie Russell yes and the realization that the Earth is the center of the universe. Genesis. Mind blown boom ... thank you Heavenly Father 🙏

@@Meson10 Its honestly a perpetual question because than it goes "well what created the diety? Another big bang", "well what created the big bang"..... Original "creation" (I dont feel that the larger measure of "the all" could of ever really ever began) is essentially a never ending and perpetual offset. We don't know...and that means none of us, to claim otherwise is a lie of hubris.

@@whatabouttheearth in which case there are only two options, either God is eternal or that the dense energy that originated the big bang is eternal in the sense of having no beginning, in which case understanding the nature of both, the question arises with the Big Bang event, which is that to produce the Big Bang a change would need to happen that triggers the event, which would mean that the energy might not be stable and being decaying for it to release energy (nuclear radiation), which would imply that an eternal state for the dense energy might not be possible because of change. But if we are to believe the initial property of a being with no begging that doesn't change, produced with his word (Gen 1 the source of creation is his word) Electromagnetic waves first (let there be light) then that could mean a release of extraordinary amounts of energy, similar to what commonly is described as the Big Bang. So the premise of a being who doesn't have a beginning might even explain the possibility of a Big starting point where lots of energy starts to expand... With this, I'm only following a natural conclusion to the statements above. Of course, that leads to the question of how can something be eternal? since we live under the common law of space and time than a being that is not ruled by space and time would be quite difficult to understand the nature of it... which is consistent with what the Bible explains on the nature of God... But well I just wanted to help and contribute a little in the conversation using the arguments above as premises... have a good day!

Yeah, I'm not part of the "everyone," either! I yelled "the TARDIS!" too! 😄❤❤

GargusSCP Exactly the same.

Orange.

Radient

it would appear whatever the color infrared length waves has to infrared sensitive eyes

@@ModerateDev not even close. Even if that species couldn't also see in our wavelengths, too! The sky would be radiant, from all directions, really. Like that image developed of the CMB radiation, it would have those kinds of microwave "colors" all over the entire cosmos!

Yeah, what was that? I was not able to concentrate on the video :/

It's CMB static

@@JonathanMoonen It's the reflection of the sea from the Earth because they didn't insulate the satellite.

Congratulations for using your own head instead of taking what's being told at face value. There is no physical way for "the light from the beginning of the universe" to reach us without some way for it to bounce off and fly back at us, because according to the Big Bang theory all light and all matter at the beginning of the universe was expanding at the same rate. What instead happens is the same problem as the temperature of Sun's corona, which is said to be at some billions of degrees, which violates thermodynamic laws. All matter radiates electromagnetic waves is all spectrums, but in different amounts. This is why you can put a filter over our Sun like pseudoscientists do and say "See, it's 15 million degrees hot!", but when you put a different filter you'll be able to also say "Look, now it's only 6 thousand degrees hot!". CMB follows the same principle, but due to distance it's more prevalent, when you apply a correct filter. For example when you look at the night sky what do you see? 99% pitch black and 1% bright dots (+/- atmospheric interference). This is the visible spectrum. It's pretty high up there, so you can only see it coming from very hot objects. But the thing is that everything with temperature higher than about 2.7K radiates in the microwave spectrum. Yes, even you, Earth and every single speck of dust between asteroids. So when if you were to look at the night sky in microwave spectrum it'd be 100% bright with no distinguishable spots. This is CMB. And somehow they propagate bullshit that's it's some "ancient light from right after the Big Bang". So that is one reason why CMB is everywhere and, say, visible spectrum isn't, but what about the cosmological horizon or why there's less galaxies the further you go? Redshift is an increase in wavelength. Energy of photon is inversely proportional to wavelength, thus redshift is a decrease in photon's energy. How do you lose energy? Working against other forces. What photon could possibly work against in space? Gravitational fields of objects. As photons move away from gravity wells they have to lose energy to escape said wells, thus with enough distance photons can redshift completely into nothingness. This is the cosmological horizon and this is also why we can't see behind it in visible spectrum, but we can still see in microwaves. I hope this answers your questions and pushes you to further inquire about such topics.

​@@LecherousLizard Wait, nobody is saying that the CMB is coming from the moment of the Big Bang. According to the video, it's coming from light that existed at some time AFTER the big bang, call it 400,000 years after or so. I don't know the exact figure. It's taken about 13.5 billion years to reach us, because the "sphere" (was it a sphere?) that existed at that time has since been expanding, so the light from that period in time had to move through ever expanding space. It's only reaching us now because that's how long it's taken to move through expanding space, which also expands the massive red-shift of that light as time has passed. So, it's not that the photons had to bounce off of something for us to see it now. From the period in time they came from, those points were "around" us already, emitting in all directions, so what we are seeing is the period of time that happens to match how long it took that light to reach us. Once again, it's NOT light from the "beginning of the universe", it's light from things that were X distance some 400,000 years after the big bang. We were part of that goop back then, but not the center; there were things around us, emitting light, and a sphere around us (our relative position back then) was emitting light that is only just now reaching us. Light from other periods in time are also hitting us all the time, but the CMB is from a very specific period in time due to the distances involved. Make sense? Long story short, it is NOT bouncing off something so we can see it. It was simply emitted a long, long time ago to cross (rapidly) expanding space, which is why it's taken so long to get here. And the CMB really was from back then. How do they know? They can calculate the temperature based on the frequency of the wave, and the fact that it is uniform in all directions where there isn't an obvious EM source. While you are correct all objects emit light in the microwave spectrum, it is NOT true that it does so at the same wavelength. The frequency of the wave varies due to temperature. Based on calculations, the CMB is from a time period where the universe would have appeared orange to us, after accounting for red-shift.

@@LecherousLizard One more thing, the redshift of the CMB is due to the expansion of the universe, the expansion of space itself. I don't really understand your explanation of redshift "working against other forces". That doesn't make sense to me. It's more like the Doppler effect, where the waves are moving through expanding space and so they are "shifted" in the red direction (longer waves) because fewer waves reach us per unit time (due to the source being in relative motion away from us).

@@Qichar Don't present that as a fact when there's no unrelated way too check it. Cosmology is currently built around the Big Bang theory which foremost and basically only proof of is the assumption of CMB being this and not something else. The expansion of the universe is something cosmologists can't measure after all those decades with each measurement giving a different value. It's borderline not science at this point, ironically, true to it's roots of trying to agree science with Catholic dogma.

@@Qichar Don't present that as a fact when there's no unrelated way too check it. Cosmology is currently built around the Big Bang theory which foremost and basically only proof of is the assumption of CMB being this and not something else. The expansion of the universe is something cosmologists can't measure after all those decades with each measurement giving a different value. It's borderline not science at this point, ironically, true to it's roots of trying to agree science with Catholic dogma.

VEGETA NOOOOOOOOOO

Vegetaaa!!!!!

+The Light There are a few in the area you call the axis of evil that would understand the consequences of the CMB existing.

The Light science doesn't like to acknowledge what happens when you apply circular harmonics to the wmap which is why it keeps getting swept under the rug

what?

I think it's a very "Biocentristic" view. Or, it's often what you want to see, not what you are actually seeing.

They just get longer

It's a bit out of my knowledge but about 10-17 million years after the big bang, the temperature of the universe would have been around room temperature so it would have already been blackened. Unless there was a place which was actually significantly cooler than its surroundings, it would have been too hot for water to be in liquid form. The cool thing though would be that that time between 10-17 million years after the big bang, liquid water could exist anywhere in the universe with the proper pressure. It was also possible, but very very rare, for rocky planets to be already formed.

Yes, the temperature at which you can heat steel and not have it glow is more than enought to evaporate water

Kieron George "... too hot for liquid water ..." The short answer is yes, since the Universe was around 3000 K at that time, and hotter before then. The longer answer is that there was no water because there was quite literally no oxygen. Elements heavier than helium wouldn't exist for some hundreds of millions of years, when they were produced inside stars.

You don't know how elements form? Maybe start there. Lmao

CMB caused by Big Bang is a self defeating concept. The "light from the beginning of the universe" had nothing to bounce of to be reradiated back at us, so how can we possibly observe it in the first place? The answer is, we shouldn't be able to. And that's why Big Bang is load of crap. CMB is a product of not only visible matter (i.e. all the galaxies we can see within the cosmological horizon), but also all the matter that's behind the cosmological horizon, but which has redshifted so much it left the visible spectrum. Note that in contrary to the "mainstream" cosmology expansion of the universe is NOT required to explain redshift, in fact it's redundant and could be the reason why "expansion is accelerating" (they are adding something that never existed and when they measure the same thing the next time, they also measure the thing you added before, thus it forever increases). Redshift is explained with nothing more, but the energy loss of photons due to effects of escaping gravitational fields. After all you can't change the speed at which photons propagate through vacuum (i.e. light), so how do you decrease energy of photon? The only variable is wavelength and by increasing photon's wavelength its energy decreases and increase in wavelength is what we call "redshift". So to answer your question: Only when there are no stars in the entire universe (and I mean ENTIRE, not just what we can see in the visible spectrum) to radiate more photons the CMB will end.

@@LecherousLizard no, you are obviously an anti-science/pseudoscience preacher of some sort. Not a thing of what you're trying to tell these people (not just this one, but all of them you're lying to) is remotely accurate! Stop claiming that you know more than all of the scientists that have spent their lifetimes studying these things! Because you simply don't.

Well, to answer you with a little more intelligence than Mister Lizard was shoveling out, there really isn't a "past us" in that sense, as it's radiating from all over the universe. There _will_ come come time when the energy waves have lost enough "oomph" (from being stretched) that they will degenerate into radio waves, instead of microwaves. The length of the waves will have been stretched enough, by the expansion of space, to where they are so long that they will be in the radio spectrum, like the cellphone radio waves, shortwave radio, then FM radio, then AM radio, then CB and amateur radio bands, and on down to longer and longer waves.

​​@@LecherousLizard this is completely false mate, where did you get this from? The very second sentence is already operating on a false assumption. You begin your idea with a mistake

@@MrMegaMetroid The second sentence may be worded poorly, yes, but that doesn't mean the rest of the comment isn't. And if you got so hung up over the second sentence so badly, then I guess you didn't read anything after anyway.

I'm guessing it would cease to exist once it's wave amplitude reached the Planck Length, but for all practical purposes it would be long gone by then.

does it exist only because we can measure it? if so then when the wavelength is too flat to measure, it will not exist.

David Smith I know I'm late but the Copenhagen interpretation of quantum mechanics is no longer widely accepted. Plz correct me if I'm wrong.

David Smith- *mind blown*

Anyone who says they know something isn't aliens is only working on a cognitive bias of being scared to be ridiculed for saying it might be aliens. To say it is definitely without evidence, is just as silly as saying it definitely isn't without evidence. That being said, it does seem extraordinarily unlikely in this case, that another race of animal from a different planet on our plane of existence have created something so massive that it emits microwaves from every conceivable direction we look. But, if we are a species that has evolved on what may be an electron of an atom as viewed from a higher dimension, it is possible that the radiation we see is residual energy from a microwave and we are atoms of three day old pasta, about to get eaten.

It's because physicists, especially astrophysicists, get constant claims from people who are sure that some phenomena or another are aliens, or that their cousin totally saw an alien spaceship one night. Actual extraterrestrial life is a very extraordinary claim and should not be believed without extraordinary evidence. It's better to say "it's never aliens, until it is," because so far, for every alien claim that had actual evidence, it's turned out to be natural phenomena.

Me 🖐

Me too 😂😂😂😂

That’s why I’m here

I've always found Jewish prophecy fascinating!

That's very interesting

It's a load of idiotic bullshit, grow the fuck up.

+Bass Dat Nope. etymonline.com/index.php?term=orange

^Thanks

in english we seemed to only have the colour once the fruit was imported, but who knows what word came first in ancient arabic. . in germanic languages it refers to fruit too, like in icelandic is aplesingalur which means 'yellow of chinese apples'

It's also a completely wrong explanation.

​@@LecherousLizard how so?

@@MrMegaMetroid Where to even start... Maybe I'll explain how CMB is obtained. The sky is measured in several distinct bands of microwave spectrum. This is essentially a 360 degree sphere around the satellite doing the measurement. Now, due to the fact we're a part of a galaxy (Milky Way) various parts of that sphere are essentially opaque. This largely depends on the band observed, but the higher (I think it was the higher, it's always a pain to find information about those bands) the frequency of the band in question, the worse the galactic interference is and in the highest bands measured it's... basically 100% of the sky. From there one needs to clean the image off those interferences. Problem is, only our own galaxy is taken into account and it's done quite arbitrarily for one simple reason. To obtain a weak signal from a strong noise you need to have either perfect knowledge of the source of the weak signal or perfect knowledge of the noise signal. We have neither. So what happens is that the initial microwave map is given a set of subtraction filters to create "anisotropy" maps. Those maps are then dubbed "CMB anisotropy maps" or "CMB" for short. They absolutely do NOT account for any of the billions of stars and galaxies that exist outside our own Milky Way and thus cannot be deemed as... what do they call it? "The oldest light"? Because that's simply not what it is, as any object above a certain temperature, even you, radiates in the microwave spectrum. The only thing CMB proves is that regardless of which direction you look, there are countless stellar objects.

Abhilash S with the orange... that would mean a lot of gamma too. I dont know...

There was no night sky or any sky at all as there weren't any planets to create shadows/night. Also you would melt.

Actually, I don't think you do, you wouldn't witness it for very long...or not at all with the instant death and all

Orange Holes😂

whoaaa

Agreed - although the popup sound that occurs occasionally reminds of the TNG door chime sound :D

Well... didn't that nearly happen when the Daleks dumped it into a huge fire, in Journey's End, when they all thought it was empty except for Donna, and then #10-two was formed from #10's hand when Donna touched it? The clear intent was to destroy the TARDIS, and they all believed it actually happened - at least, the Doctor didn't let on that he believed otherwise, if any psychic connection he had with the TARDIS told him it wasn't really destroyed. And then #10-two and Doctor Donna, both from the human-timelord metacrisis, saved the day, except they had to leave #10-two in the alternate universe with Rose (which made her happy, at least), and then Donna had to have her memories removed, so the Doctor part of her wouldn't kill her human body... and I always ugly cry during that episode! Ah, Doctor Who... my very favorite show of all time!

It is considered homogeneous on large enough scales. yeah, so this was asked 2 years ago.

@@borisjohnson1944 On large enough scales. LOL.

Yes. Do you have a problem with that?

en.wikipedia.org/wiki/Cosmological_principle

@@borisjohnson1944 Sorry if I questioned your belief. No offence intended. Great source.

Yes

+Ernest Choy According to Family-Guy, God farted and used a lighter to flint a spark in that gas cloud, near his rear end.. It exploded, there was a fire ball.. and there was light.. along with galaxies.. Such a source MUST leave some eternal-holy-radiation out there.. :)

Ernest Choy, there was no big bang. The CMB is literally a photoshop creation and given a title by some imaginative artists who manipulated recorded data using all kinds of signal processing no-no's. The whole notion that the "background" picked up by our observations is a remnant of the primordial "big bang" is complete gibberish. Here's why. Our own galaxy produces so much noise on the plane of the galaxy that the background is hidden behind a foreground signal over 1000 times as powerful. It is impossible to pull a background signal from the foreground under that condition. The next problem is that the instruments creating the so-called background map at the shortest wavelengths have only a 0.25 degree resolution of the sky (NASA's own numbers). The lower frequencies have only a 1 degree resolution of the sky. In the case of the smaller, finer resolution region, there are over 1 MILLION galactic sources alone in each pixel, all of which produce signals like OUR galaxy that swamp whatever background signal there might be. Again, it is IMPOSSIBLE to separate the 1 MILLION galactic sources in each pixel from the measly background signal. Whatever these blowhards tell you about the CMB is nothing but BS. They literally have no idea what the background of the universe looks like.

@@t00by00zer So what about the ESA Planck mission? There have been several readings of the cosmic Microwave Radiation Background. Are you aware of the WMAP results? It verified the results from the COBE satellite. Also, the Universe is a prolific source of microwaves. The intensity of COSMIC microwaves is as great as the brightness of the Milky Way if we imagined the Milky Way to extend over the entire sky. How could we possibly cause any interference to such an uniform signal? The intensity of the background radiation had been measured at many different Wavelenghts. Before stating misinformation I really suggest you look at the original papers by Arno Penzias and Robert Wilson. Also the ESA Planck results: archive.nytimes.com/www.nytimes.com/interactive/2013/03/21/science/space/0321-universe.html

@@t00by00zer Also you maybe want to research the NASA WMAP Satellite results. Just because YOU "believe" something to be impossible doesn't mean that it actually IS impossible. The WMAP Satellite provided ridiculous accuracy with near perfect measurements providing accuracy of one millionth of a degree!!!

Raydensheraj, No matter which direction you point the Hubble telescope, or any telescope for that matter, and if you leave it in that position, gathering light for hour after hour, you will see an immense number of galaxies. (See Hubble Deep Field, or, Hubble Ultra Deep Field) The Hubble telescope has an angular resolution many orders of magnitude higher than any of the microwave satellites sent to study the "background." The WMAP images have a resolution of about .3 degree. Hubble has a resolution of about .05 arc seconds. In other words, Hubble has over 20,000 times the resolution of the CMB maps. And when I say "degrees" I'm talking about ANGULAR degrees. In every single pixel of the CMB there are over 1,000,000 galactic radio sources emitting radiation in the same bands studied by PLANK. You tell me, Raydensheraj, how does the NASA team of "scientists" ignore those galactic sources and arrive at a "background?" It is utter nonsense to make the claim that they are measuring the temperature of the primordial background. They are measuring the microwave output of TRILLIONS OF DISTANT GALAXIES! The galaxies cover the sky in every direction, varying in their distribution density somewhat, but on average, their distribution looks exactly like the CMB. What a coincidence!!! Have you ever bothered to look at the raw data from PLANK? I have. Their conclusions, and the final map put out for public consumption, is a complete joke, a total fraud.

@Paweł Jarosz But first Trump must cool down. Not likely in a foreseeable future.

Gareth Dean "... would have formed two 'bursts' of atom forming ..." The emission of the CMB wasn't an instantaneous event; but rather happened over a period of some 100,000 years. "... absorbing the CMB ..." The CMB is quite faint, but in principle, you can build an apparatus to gather and store the energy of _any_ electromagnetic radiation.