When I saw the title I was like "This is so obvious, any 3 year old knows it" After a minute of starting watching it, I was like "Shit, I don't know shit"
@michaelunderhill54978 жыл бұрын
XD Same
@paolopatron54118 жыл бұрын
More like "lol I know this stuff" then he goes "actually, it's not that, there's this other explanation" then when I go "ohhh that makes sense" he goes "actually, that's not it either, here's another explanation" then he does this three more times
@KiDxNyu8 жыл бұрын
The answer is obvious, its dark so you can sleep better.
@LossOfEternal8 жыл бұрын
Lol
@Titanic-wo6bq8 жыл бұрын
Y Y Y Y Y Y
@Yottifferent7 жыл бұрын
Bizmarkk i am reading this commment at 10 pm
@condor07uk7 жыл бұрын
not true for people who live near arctic poles
@user-kx6gr6ky4b6 жыл бұрын
Bismarck that's so true man👍
@invertedgames79938 жыл бұрын
yes, inject the knowledge into my veins!
@gangstermedia90397 жыл бұрын
Bullshit knowledge
@invertedgames79937 жыл бұрын
Ian Last replied
@hazri87585 жыл бұрын
@@tomascanevaro4292 you really love streotyping people I see
@ishworshrestha35594 жыл бұрын
Ol
@oshiriz64863 жыл бұрын
.
@cloviscareca9 жыл бұрын
Vsauce, Minutephysics, Periodic videos..... An incredible and unbelievable playlist for the weekend :)
@raykent32119 жыл бұрын
You might like to add Sixty Symbols for next weekend (I'm a fan)
@vesteel9 жыл бұрын
Matheus Bitencourt and numberphile, Minuteearth and CGP Grey?
@GeekyStuffVerified9 жыл бұрын
:)
@yuichilee969 жыл бұрын
+Matheus Bitencourt SciShow, Crashcourse and Veritasium?
@aishwaryasriram73718 жыл бұрын
ASAPscience!!
@AldirneXd11111110 жыл бұрын
SO if aliens are observing us they see a dinosaur?
@InvokingPeace10 жыл бұрын
pretty much
@ghostlourde270010 жыл бұрын
Unless we figure out how to time travel. then they might see us looking at the dinosaurs. or perhaps we time travel to stop ourselves from time travelling, 1 + -1 style.
@gabepatton985110 жыл бұрын
***** Although, because of the motion of the Galaxy/Solar System/Earth, time travel would have to include some way to account for literally everything in the universe, as well as a way to get to the earth to actually see it during that time, instead of just the point in space that earth is in the time you're travelling from. Furthermore, we would have to measure the speed and direction of everything in the universe also, to find where it was/will be or else we run the risk of traveling to a time during which the place that you are now was in fact occupied by some asteroid. This would likely result in the destruction of what is known as you, as all of the electrons/neutrons/protons that you are made up of would be scrambled among those that made up said asteroid, and this would cause the creation of new particles as all of the electrons ... etc mixed and combined in ways that neither your bod nor the asteroid had them in before. Basically, time travel would be extremely dangerous without a dizzying amount of math.
@keithvrotsos384310 жыл бұрын
That appears to be the train of logic implied... so I guess.
@MaxoRedstoneo10 жыл бұрын
i think, as far as i know
@beccasiciliano93111 жыл бұрын
I asked this question in my 8th grade science class. My teacher didn't have an answer. A few years later I asked my dad. We thought about it and this is the answer we came up with. I am so excited this video exists because I've been asking this question for years. Thank you.
@adrianshuh-humphries39155 жыл бұрын
shouldn't ultraviolet and x-ray light from ultra-distant stars get redshifted into the visible spectrum?
@sodr74405 жыл бұрын
Oh yes ????
@sodr74405 жыл бұрын
May be there is a lot less ultraviolet light than infrared? so when they redshift to visible spectrum, they remain not intense enough for us to be able to see it
@mikethespike0565 жыл бұрын
Wow
@kenivia94765 жыл бұрын
probably would just look like a normal star to naked eyes tho cos they must be like super distant
@dreamyrhodes5 жыл бұрын
It does. The quasars we see from almost 13 b light years away are radiating heavily in the UV and X-Ray spectrum but we still see them all red. And the backgound light is shifted even more, into microwaves. That's why the cosmic background is a microwave background which equals a temperature of 3.15 K or -270°C so all the light from the big bang reaches us as 3 K radiation.
@Yves_Zhou8 жыл бұрын
i am even more confused after i finished watching this vid, sos
@yjk928 жыл бұрын
Well, you know a lightyear is the amount of distance light travels in one year, right? So if you look at a star 1 lightyear away, you get the image of the star with 1 year delay, since the light you just got started traveling 1 year ago. if a new star popped up 2 million years ago, but the distance between this star and our Earth is 1 million lightyears, we still need to wait 1 million more years for that light(the image of the star) to arrive. That is why we can't see a lot of stars that certainly exist. Light is so slow that it takes time to reach us. Also many stars' light is out of our visible spectrum. Kinda like how some animals can hear sound that is too high or low for humans to hear, there are light that only machines can see.
@Newstory7378 жыл бұрын
Light is fast I believe.. Just the space between the star and our planet seems to be very, very big :)
@yes123378 жыл бұрын
light is a wave, yes? So then imagine throwing a stone in the Pacific Ocean and waiting to see the wave on the coast of Europe.
@gabrielbrady14718 жыл бұрын
the reason its dark is because the universe is infinitely large and growing that the light from the big bang hasn't reached us yet but when it does the night sky will be light if that makes any sense to you if it don't forget everything that I just said
@samihaislam34877 жыл бұрын
Infrared radiation is outside of our visible limit. Humans cannot see it.
@h4happy3097 жыл бұрын
Videos like this are the reason why I LOVE physics 💚 Thankyou for the great work! continue doing so :)
@davidshtayfman75210 жыл бұрын
This is a lot better than the 10 second videos.
@haiggoh10 жыл бұрын
I want infrared vision :(
@SreenikethanI5 жыл бұрын
But you'll see every object on earth glowing eerily like hell
@iammaybeasliceofpie46745 жыл бұрын
Become a bee!
@ricardoalves96055 жыл бұрын
haiggoh The atmosphere would absorve the infrared coming from the sky And everything would glow
@missingpatel73495 жыл бұрын
Infrared vision is good. But the question is... how much infrared?
@leoroastkarega37534 жыл бұрын
Buy infrared binoculars
@CupojoePro10 жыл бұрын
2:26 is not to scale children!
@MSpacer10 жыл бұрын
Well, duh.
@brendarojas56134 жыл бұрын
Humans aren't as tall as Earth???
@Keredx8910 жыл бұрын
Hold on a second! Wouldn't the redshifting get the ultraviolet radiation from distant stars and galaxies into the visible spectrum in a similar way? So what's going on there?
@muthukumaranl5 жыл бұрын
i have the same doubt too..
@passthebutterrobot26005 жыл бұрын
That's a very good point! Anyone know?
@deadat25 жыл бұрын
Well sure it's just that the range of visible is fairly small Red700nm-violet400nm. Redhift is just the measurement of the change in wave length of light that say a hydrogen atom emits divided by it's rest wavelength. So really the question is kind of irrelevant with the scales we are talking about anything close enough to be in the visible spectrum is to close to matter. skyserver.sdss.org/dr1/en/proj/basic/universe/redshifts.asp www.space.com/25732-redshift-blueshift.html science.nasa.gov/ems/09_visiblelight
@vornamenachname52675 жыл бұрын
You are right, but the ultraviolet radiation from even more distant stars gets redshifted even more. Therefore it too becomes infrared. So there is a zone where you can see the 'ultraviolet' light, but farther away, you can't.
@MrLaptopus4 жыл бұрын
Good question. This video is false and just a misdirection into Big Bang, etc. The reason the sky is dark is because density of light reaching us is low.
@missingpatel73495 жыл бұрын
This is the only channel which gives me answers about cosmos without giving me existential dread
@ricochet1889 жыл бұрын
I can't believe I never knew what the term "infrared" actually meant until now.
@ricochet1889 жыл бұрын
I got that from the video. Thankyou.
@rescuecatHQ9 жыл бұрын
***** so what is microwaves?
@pyramidblack8 жыл бұрын
+Julien12150 thanks wiki
@Sontraid8 жыл бұрын
Is there a wavelength higher then 1 meter? Like 2 meter or even a kilometer?
@pyramidblack8 жыл бұрын
+Sontraid 10 m is decimeters but its rarely used 100 is hektometers and 1000 is kilometers
@raychumon10 жыл бұрын
does this mean if we could perceive infrared light with our human eyes, the sky WOULD be full of light at all times?
@TheThundercool10 жыл бұрын
It means that, if we were able to see in a wider spectrum of light (e.g. infrared, ultraviolet, or more), we would see many other things that are invisible to our current capacities...
@Evan_Case10 жыл бұрын
If we could see in Microwaves you would see the CMB (Cosmic Microwave Background) everywhere....
@KasisnuSingh9 жыл бұрын
Actually you would have to wait a really long time! There would be stars that are far enough that light from them hasn't reached us yet!. The background radiation would be visible as well.. something. A lot depends on how we would actually perceive the radiation. I assume you assumed there was no atmosphere! :)
@nicolasiguaran9 жыл бұрын
Tethloach Kingofreason Ehmmm. I may think you are wrong. The thing the haets up the earth is not the light, it is the infrared thingies. That we could see them doesn't mean there would be more of it and so the earth's temperature would stay the same. It would be a lot lot brighter, though.
@KasisnuSingh9 жыл бұрын
Tethloach Kingofreason Not quite. The light spreads out. The further away we are, the less intense it actually is. nicolasiguaran You're close. So both infrared and "light" are the same thing here. *We* can see one and not the other. And thanks, my comment above was partly flawed. Updated! Also, we need the atmosphere for the earth to *stay* warm. Think of other planets or the moon. It can get quite warm during the day but then also quite chilly at night. The reason that happens to a lesser degree on earth is due to the presence of greenhouse gases(in the atmosphere).
@demonhunter50511 жыл бұрын
Yes. I saw a picture sometime (an artist's rendition I think, or maybe a simulation) that basically measured the strength and wavelength detection of the creature's (I think it was a lizard or chameleon of some kind) eyes and then took a picture of the night sky with those wavelengths, combined it with visible light (I think it sees in the spectrum we see, along with infrared) and vuala. You'd have to do some searching for it, but if I remember the article right, that sums it up.
@Spinodal234 жыл бұрын
2:57 Korean Subtitles Typo - "자외선" should be "적외선"
@zwz.zdenek10 жыл бұрын
You forgot one piece of the mosaic - there is actually a "border" beyond which we cannot see. It is where the expansion reaches the speed of light from us. The area of this sphere is said to contain all of the entropy information in our observable universe. There is no classic hard barrier, but the laws of physics make it so that we cannot ever see or get past it.
@shabsi77010 жыл бұрын
למעלה מגלגל התשיעי, אין שם לא מקום ולא רקות.
@debmalyaroy58706 жыл бұрын
One of the best videos I have ever seen. This channel is so wonderful. Great job!
@elenaalex45888 жыл бұрын
what a complicated answer for a simple question
@BrickBuster25528 жыл бұрын
"Y me no see night?" "2 red"
@Titanic-wo6bq8 жыл бұрын
dat explains it
@EmilioKolomenski7 жыл бұрын
Start your own science channel, you can call it "SecondPhysics"
@gangstermedia90397 жыл бұрын
because it is all bullshit
@raghavnandyal15187 жыл бұрын
It's that simple. It's something called the Oliver's paradox, which is still unsolved. It basically says, if there's an infinite number of stars, then why is there light in every direction you look?
@coasterrick9 жыл бұрын
damn I wish I was brainy so I could understand this stuff. If they teached this in school id of listened all I remember doing in physics is connecting a fucking battery circuit to a few little bulbs
@ErojFeeding9 жыл бұрын
Its not that hard you just have to understand the basics at first :P
@LucaPed949 жыл бұрын
Slick Rick Taught*
@ree83ce9 жыл бұрын
Could be worse + Slick Rick all I do in science is burn stuff ( ussually salt water or something else added to pure water that that dose or dose not dissolve in it ) to learn diffrent things like, why salt dosent evaporate or how to get clean water or somthing wired, I mean, dont get me wrong, you put fire into a lesson, I aint complaining.... unless I get burnt by the fire then ill be a little mad lol
@dee81637 жыл бұрын
tell me about it. we keep learning about how light gets reflected or refracted by glass, mirror etc etc
@meryemrashidova59846 жыл бұрын
This is what we are learning in Physics just now
@Sinan970828 жыл бұрын
BRAINGASMS!!! I love this stuff, it stimulates my brain somehow. Started to study again with 30 and I would recommend to others too who feel stuck in life or in their job and generally considers learning as a never ending process and enjoys it. Thanks to all the people who do this stuff (Vsauce, RSA, MinutePhysics, FightMediocrity, Brian Johnson, Elliot Hulse and so on) Any Recommendations refering to similar Videos? Education, Psychology, Self Development, ... would be apreciated.
@Huu1598 жыл бұрын
Try In A Nutshell/Kurzgesagt
@Sinan970828 жыл бұрын
Akshay 28392 Warum kurzgesagt?
@Huu1598 жыл бұрын
+Sinano That was the earlier name of the channel. They explain big concepts in short videos hence "kurzgesagt"
@ash.junaid8 жыл бұрын
+Sinano Good to hear it man. I'm kinda in a similar situation right now. Check out Numberphile as well. Can't recommend it enough =)
@Sinan970828 жыл бұрын
Akshay 28392 Vielen Dank für den Hinweis :)
@thealphareject10 жыл бұрын
These minute physics are so interesting. I don't understand why so many people don't like it, is it that they don't understand it? I personally thinks it's cool!
@susanlegeza7562 Жыл бұрын
Love these to the point explanations!!!
@lauralopezbueno53511 жыл бұрын
This is almost unbearably beautiful. Thanks!
@mrvlhs10 жыл бұрын
This was amazing. I never really got a reason to admire astronomy but this is a great one, thanks! :)
@NickBeatoMusic10 жыл бұрын
Uni = One Verse= A Spoken Phrase Genesis 1:1 - "Let There Be..." Ladies And Gentlemen, The Universe
@zwz.zdenek10 жыл бұрын
Must...not...take...the...bait!!!
@NickBeatoMusic10 жыл бұрын
Cancer isn't contagious o.o lol just joking :) I can understand your motives ^_^
@ThaMinecraftNetwork10 жыл бұрын
Religious bait....so tasty...yet so dangerous...SCREW IT. The bible is a lie, get over it.
@technichy36339 жыл бұрын
Universe comes from the Latin word "Universus" which means whole
@osoco72949 жыл бұрын
ERROR IN THIS VIDEO? "If we lived in an infinite, unchanging universe, the entire sky would be as bright as the sun." Excuse my english, but my small brain tells me that's not how it goes at all. In my opinion, the most important thing is ratio between bright objects empty (lightless) space. Emptiness wins - big time. I also think that - in this context - this is also the most important thing in real, expanding universe, and red shift effect starts to affect in VERY distant objects. If the red shift were the main reason, we should see dark red(ish), not black background. Feel free to correct.
@jamescarwyncandila80449 жыл бұрын
OSOCO Yes? I agree in some part of your opinion. And that it is in the last part of it. We would see some kind of a dark reddish thing. Yeah, we will be able to see some dark reddish thing. But not the whole background of it. Because, As something gets redder, it gets more... well.. dark. And as it reach it's point where literally it's infrared. It would become, black. Because we cannot see it anymore. But if the theory was true, (The theory that I'm talking about is the Infrared thing.) Some animals like boas, will see the night with a lot of red stuff but not totally all. Because some far things are so infrared, that even animals that can see them, won't be able to see them. I hope you get my point.
@osoco72949 жыл бұрын
Jemas Dilacan That's pretty much how I think. Anyhow, in my opinion there should be the the whole range of light (because of different red shift levels and distances) from white to invisible infrared added (mixed) TOGETHER, sum total being somewhere between orage and dark red to human eye. That's not the case, so 'emptiness explanation' seems to be WAY more important factor in blackness phenomenon. In that light (no pun intended) there can not be an entity percieving infrared, because of very small percentage of visible objects compared to emptiness in the first place. This is rather hard to explain with my great English skills, lol.
@jamescarwyncandila80449 жыл бұрын
OSOCO Nice Englishy things! Anyways, Yeah. You're right. But we don't really know what will be the real factor. But I accept both as a factor. Do you?
@osoco72949 жыл бұрын
Jemas Dilacan 'Sum total' is probably wrong term. 'The result of mixed frequencies' may be more correct. "But I accept both as a factor. Do you?" Both factors are real and effective, but I don't agree with this: "If we lived in an infinite, unchanging universe, the entire sky would be as bright as the sun." That's because of 'emptiness wins' circumstance, thus we don't see the effect of red shift factor in the lack of enough light coming to us in the first place, let alone the dimmer light affected by the red shift.
@jamescarwyncandila80449 жыл бұрын
OSOCO Exactly
@alexcondurache10 жыл бұрын
a question .. if I'm on earth and you are on a planet one light-year away from me, and suddenly your planet explodes, but you're sending me a voice message in the exact time .. what reach to me first? your voice, or the light from the explosion?
@BenjaminStewart610 жыл бұрын
It depends on how the voice message is being sent. If it is radio or any other form of communication that uses the electromagnetic spectrum, then my voice being cut off would happen at the exact same time as the explosion, since light and radio waves are both on the electromagnetic spectrum.
@aaronreid578910 жыл бұрын
his body would reach u first lol
@mahmouduthman38210 жыл бұрын
Benjamin Stewart true, but given that the sound was send in the form of a message transmitted using electromagnetic radiation shouldn't it take extra x time to encode & decode the message content back into sound (Voice) ?
@MoAli7210 жыл бұрын
I still don't get it.
@lars123mc10 жыл бұрын
my mouth: intresting my brain: durrrr
@shynnsup838310 жыл бұрын
Red Shift. Thats all you need to know.
@MoAli7210 жыл бұрын
Shynn Sup Now I need to know what 'Red Shift' is... :s
@shynnsup838310 жыл бұрын
Mohammed Ali Light changing its wavelength into infrared.
@vottoduder10 жыл бұрын
Mohammed Ali Red shift is the same concept as when you hear a police car siren traveling away from you except in the form of light waves instead of sound waves.
@ricardopadua5180 Жыл бұрын
Very cool video, but I think the main cause is the inverse square law: the intensity of the emitted light decreases with the square of the propagated distance. Because the stars are far way most of their light arrives with intensity below our eyes sensitivity threshold.
@domishbk11 жыл бұрын
Lean back :)
@MeronBridgeMR8 жыл бұрын
This is awesome, I never thought that a certain wavelength light emitted from a moving star would actually appear as another wavelength to us I assume that is because of the Lorentz transformation... but if so shouldn't the wavelength actually "become" shorter relatively to us?
@MeronBridgeMR8 жыл бұрын
(Like becoming UV instead of IR)
@patrickhector8 жыл бұрын
As space grows, the spaces between everything grows. This includes the space between different adjacent waves in a beam of light, essentially making the wavelength longer. Another thing is that as objects creating any sort of wave moves away from an observer, the individual waves are made farther apart, making the wavelength longer. What you're thinking about is *blue*shift, so named because when an object is moving toward an observer fast enough, any light released appears slightly blue because the individual waves are released closer together.
@MeronBridgeMR8 жыл бұрын
+Patrick Hector That makes sense. Now I have to explore this topic further :D Thanks!
@Broockle9 жыл бұрын
Stars that are super far away also become etremely dim by the time they reach earth so that our human eyes couldn't see them even if their light was in the visible spectrum. We would still need telescopes to see them anyway.
@juanova55304 жыл бұрын
FINALLY,someone who can answer my "out-of-this-world questions"!
@purplepeoplepurple10 жыл бұрын
A good explanation, if a little hurried. The music, though, was a distraction - too loud.
@Pierrot11019410 жыл бұрын
Well, the channel is called "MinutePhysics"...
@jameslolan82910 жыл бұрын
Peter Pepper yeah not "HourPhysics" explaining every single fact about one thing!
@number001710 жыл бұрын
I always thought because the dark matter clouds cover a ton of light or bends light lol
@RICE4azns10 жыл бұрын
It's not called Dark Matter because it's dark. It's called Dark Matter because it is utterly invisible across all spectra of light, only detectable by its gravity. Galaxies are formed at dark matter clumps, so if anything, all the gravity would bend light into galaxies, enabling viewers to see more light.
@MichaelBernardo10 жыл бұрын
Haha what a great way of looking at it no pun intended. I never thought of that. Great video.
@solocani10 жыл бұрын
I believe that Cosmic Microwave Background isn't only beyond the stars but simply everywhere in space/time. Anyhow i think you've done a great video, I love it!!! :)
@mmartinisgreat8 жыл бұрын
question. can some one be looking back in time at us??
@Poulpink8 жыл бұрын
yes
@RichardPugsley8 жыл бұрын
So if we had a way to travel really fast to another place far from earth and than look at a certain place on earth, we could see who commited a murder for example...
@carloshgrant8 жыл бұрын
so to answer you question simply, yes. if you go one light year away from earth and if you could look at it with a telescope, the image you see is 1 year old. it looks like you are watching live events on earth (clouds moving and all) but it all happened one year before. thats just because light has a finite speed and it takes time for it to travel.
@dmmm8767 жыл бұрын
Yeah, as Carlos Grant said, 'if you go one light year away from earth and if you could look at it with a telescope, the image you see is 1 year old'. The only problem with doing it: it would only really work if we could instantly teleport one lightyear away, or if we could travel faster than the speed of light. Because we'd need to travel a lightyear away from the Earth faster than the light itself can get there. For example, if we have a race and you start a month earlier than I do, I'd need to drive much much faster than you are, otherwise I'd never catch up. The same sorta thing applies here. To see even a month into the past, we'd need to travel impossibly fast to catch up with the light that got sent out a month ago. It's still cool to think about though.
@prodbylukee7 жыл бұрын
If a species on an other planet had a very massive telescope (like 4 light years across) and they were observing us from 65 million light years aways, they could theoretically see dinosaurs.
@wesmo_8 жыл бұрын
Oudated. Parts of Universe are expanding, other are retracting. Conclusion: We don't know what the hell is going on out there.
@hrnekbezucha9 жыл бұрын
So if we would see infrared, sky would be full of stars all the time?
@coolipopy9 жыл бұрын
Hrnek Bezucha There are longer wavelengths than infrared
@justinlewtp9 жыл бұрын
There is a wavelength called far-infared. So the light will be that, as it is moving away
@MartinBrada9 жыл бұрын
And the cosmic microwave backgroud, as you can see from the name, is microwave.
@MrWestSky6 жыл бұрын
The atmosphere won't let infrared light past through into the Earth, that's the point of it. Hubble can take pics of it because it's in outter space. So if we were sensitive to infrared, we'd still see the night sky dark.
@princesselina60728 жыл бұрын
Omg I love space! It is so cool and it is so fun to know more and more
@CatalystEXE10 жыл бұрын
interadesting
@williamwatson37038 жыл бұрын
I thought the reason the sky was dark at because we were so far away from other stars
@01rai018 жыл бұрын
olber's paradox
@MegaBanne8 жыл бұрын
It is BS.
@01rai018 жыл бұрын
***** it is, leads to an understanding of doppler shift, cmb, etc
@MegaBanne8 жыл бұрын
rai ZOR Not realy olber's paradox is based on asumptions that violates the conservation of energy. Some believe that big bang resolved a physical paradox, but there never was any to begin with.
@01rai018 жыл бұрын
***** you misunderstand what I'm getting at
@MegaBanne8 жыл бұрын
rai ZOR ok
@godnyx117 Жыл бұрын
Good old LEGENDARY early 10s!!!! The best period for someone to be alive! Amazing video my friend!
@john42t9 жыл бұрын
There's a simpler reason: The stars are too far away and not bright enough. Virtually all stars the naked eyes can see are in our own galaxy. Even the Andromeda galaxy, which is really close and consists of numerous stars, is barely visible. So the fact that star's aren't visible from the universe outside our own galaxy with the naked eye has barely anything to do with the reasons given.
@chakaval1009 жыл бұрын
Agreed. I think it is like trying to see a candle light miles / kilometers away.
@Oinikis9 жыл бұрын
That's not true. For exmaple, if we double the distance between us and a star, we will receive 4 times less light, however, it will take up 4 times less area of our vision, so since they both change at the same rate, when an object is moved away from us it only gets smaller in out field of view, but the brightness density stays the same. For example: if you place a computer screen far enough, you won't be able to see individual pixels, but you could still see the screen. and if you move it so far away you can't see the screen, you can stack screens on top of each other and to the side, and still see them, and if you leave no gaps, it will still have same brightness. This is both beautiful, and scary.
@john42t9 жыл бұрын
Oinikis If you leave no gaps, yes. Space, though, is mostly empty, and even the gap-to-no-gap ratio is "almost all gap".
@Oinikis9 жыл бұрын
But if space is infinite and eternal, then there would be no gaps. This prooves universe had a beggining
@john42t9 жыл бұрын
Oinikis It's an interesting argument. Disregarding speed of light and assuming an average star density, an infinite universe should look infinitely bright. I'm pretty confident that the following holds for our universe though: Earth is part of a larger galaxy. If you'd look outside the window of a spaceship at a suitable point far away from any galaxy inside the local group, you'd possibly see two faint dots in the entire sky and nothing else (Milky Way and Andromeda). If you'd move far away from the local group into intergalatic space, you'd see nothing at all. Complete and total blackness. And that even holds if you remain in an area of the universe with a high density in galaxies. Most of the space is located in great voids that are particularly empty. So if you move away from our galaxy you usually get into space ever and ever more devoid of stars by orders of magnitude. However, that doesn't really refute your argument. Since if, regardless of how far you go, the density of stars remains constant over sufficiently large areas of space (we're thinking truly vast areas of space though), it should still be true that the average perceived brightness should even be infinite (if I think correctly here). There is, however, also the speed of light taken into account. The farer you look the more you look into the past. Indeed you can see "light" from all directions in the form of background radiation as talked about in the video. So the distance you can see is in fact limited by the age of the universe times the speed of light.
@highseas10368 жыл бұрын
I thought I knew shit?!
@emersonsrandomvideos2488 жыл бұрын
it is dark at night because batman wants it. He is the dark knight.
@toastedclubsandwich8 жыл бұрын
Thank you, Homo Erectus.
@stevencarlson542010 жыл бұрын
Couldn't it also be that the light coming to us from stars is pretty much parallel to our line if sight? It's like looking at a flashlight through a pin hole. The flashlight itself is bright but it's being restricted to parallel rays, much like the stars which are far away so we only see parallel rays. I think either way is a good explanation.
@thelitcandle70369 жыл бұрын
Does dark matter have to do with why the Cosmos is so dark?
@breakthewastedspace8 жыл бұрын
Dark matter is invisible
@rizzley9808 жыл бұрын
But how can you explain blackhole? Dark matter + particles + vortex .. You can see neither and light can't get pass through it because it is so dark
@AlchemistOfNirnroot8 жыл бұрын
+Trainer_Poke Doesn't interact via the electromagnetic force*
@sarukegirl10 жыл бұрын
brain fart. i have to write a two page paper on this. you covered it in 3 mins. and im still slightly confused LOL
@MrHorimiya10 жыл бұрын
Geez you're asian, you should understand !
@birk734810 жыл бұрын
Only 2 pages!?
@CrazyDoug179 жыл бұрын
***** What is an ''Azians'' ?
@alecbeach49110 жыл бұрын
I DON'T UNDERSTAND! THIS MAKES ME ANGRY!
@michychu38735 жыл бұрын
Alec Beach ikr
@zthecat3 жыл бұрын
This video answered a question I didn't know I had
@scotttimothy6410 жыл бұрын
Thanks. Now I won't be able to sleep at night.
@nora36169 жыл бұрын
Who else came here from Vsauce?
@ahmedalmatari97589 жыл бұрын
Noura Alzarouni I came here from searching up the best science youtube channels.
@69Solo8 жыл бұрын
+Noura Alzarouni Not exactly! I been spying on you for quite a while. So where ever you go, I go. @_@
@davetylerii89856 жыл бұрын
Noura Alzarouni I came here from Vsauce
@samslostshoe10 жыл бұрын
NO EDGE!
@PedroHenriqueScloneski10 жыл бұрын
DUDE, NO EDGE!
@RMoribayashi9 жыл бұрын
I think Henry had been reading Isaac Asimov's classic story Nightfall when he came up with this topic. It's about a planet in a multiple star system that only sees the night sky for a few hours every 2000 years.
@amandahiya9410 жыл бұрын
i dont understand :( !!!!
@quinnbaugh239810 жыл бұрын
As we know space is expanding, the stars are moving away. And the farther they are from us the faster the stars travel. As it goes on and on it becomes redder and redder until we can't see it anymore (at least with a naked eye). That's why it's dark at night, Aman Dahiya. :) : D
@metalvinnyofficial10 жыл бұрын
Humans can't see infrared light.
@amandahiya9410 жыл бұрын
Cool Math huh?
@flaminggaming462110 жыл бұрын
Aman Dahiya Space is always expanding, and the stars are moving with it, and as space gets bigger, and the stars get further away, they become red. As all this happens, space gets bigger, causing the stars to get farther away, making them get redder, they go infrared, which the human eye cannot see.
@WJames-nq2df6 жыл бұрын
Also factoring in the time between when you see a star and when a star is either created or when it dies. The blank spots may be home to stars that produce light which will never reach the human eye due to the long distance. And the stars that are there may have died long before humans came around but because they're so far away and the speed of light is so limited, the light those stars shone will be seen long after humans no longer exist.
@helens.undead6668 жыл бұрын
It's not that the dark is at night, it's that when the dark came, people called it night.
@alwaysthelight7 жыл бұрын
its because the Dark travels faster than Light
@gangstermedia90397 жыл бұрын
lol
@consmos3 жыл бұрын
Before digital TV, I used to love turning analogue TVs to static and just basking in the knowledge that I'm watching leftover signals of the big bang, populating throughout space in every direction. And also some random noise generated from Earthbound sources, for those pedantic enough to split hairs.
@blazinchalice10 жыл бұрын
I'm pretty sure dust has a lot to do with it, too.
@albionxhediku97885 жыл бұрын
no
@Munibahmad24110 жыл бұрын
IN ENGLISH PLEASE? -MINUTEPHYSICS
@bigballsgame559110 жыл бұрын
Fuck, I didn't know why I wanted to kill myself, until I realized I was in the nerdy part of KZbin.
@TheFishCostume10 жыл бұрын
I don't understand that, but okay.
@bigballsgame559110 жыл бұрын
You can call "science" the theoretical development of techniques meant to improve your sex life. Asking whether the sky is dark or not when, for all intensive purposes, it is and forever will be pitch fucking dark, is not just nerdy, but virgin fucking lame. I can't believe how you try to pull me into your fucking lame sad world.
@l3orn2Film10 жыл бұрын
bigballsgame Nobody tries to pull you into anything, you came here you fuck face. Fuck off
@Chordseeker10 жыл бұрын
bigballsgame rofl, you made my day. :D Not sure if joking or trolling, but you are surely free to go spend your quality time improving you sex life then learning something, unless it is less "science" and more "science-fiction" for you. :)
@Jaspertt110 жыл бұрын
Go to your cave... You won't get much more if you don't appreciate this stuff ;)
@sohailansari26737 жыл бұрын
MAN! where do you get this sort of information? You truly deserve a nobel.
@harrybullocks35311 жыл бұрын
Wait. If the universe is infinite in the space it occupies then how can it expand?
@freedfighter9610 жыл бұрын
It's not infinite
@Alexandra-ip2by6 жыл бұрын
Dun dun dunnnnnnn
@seanspacey44526 жыл бұрын
The idea is that if the universe is infinite, spacetime expands into itself. It's not that easy to visualize and I couldn't find a nice gif but here is a good video that helps: kzbin.info/www/bejne/oYeWZKduipuqaJo But the same question can be asked for a universe with curvature. If the universe is not infinite, it would still have to expand into itself because there is no such thing as "outside" of the universe because outside refers to a position and position only exists within our universe because there is spatial dimensions.
@LukeRileyA9 жыл бұрын
Well, why isn't the sky red then?
@marieflynn94209 жыл бұрын
Luke Riley Because it's infrared which is impossible to see with the naked eye.
@coolipopy9 жыл бұрын
Luke Riley Eh. Rayleigh scattering
@janablahova81169 жыл бұрын
Luke Riley Ha, ha... good qestion
@dependent-wafer-1779 жыл бұрын
+Luke Riley Dude really?
@dependent-wafer-1779 жыл бұрын
+Jana Blahová Erm no not a good question, INFRARED doesn't mean you can see it, infrared is invisible to our eyes like the guy kept on saying in the video jeez
@supertuesday60010 жыл бұрын
I don't like his accent. He keeps using that irritating tone~ towards the end of most sentences...
@crobatron680210 жыл бұрын
you little mean person
@musicboxer110 жыл бұрын
I don't like you :)
@HolaMiMundo9 жыл бұрын
I believe that there may be 2 flaw in this video: As visible light red-shift to IR, UV light would red-shift to visible light. “No matter what direction you pick, you should always see a star or a galaxy, so the whole sky should be as bright as the sun”… the infinite sum of finite numbers (limit of a serie) may be a finite number, then, if this number is small enough (bellow how much you eye can pick up light), the sky may remain dark.
@gretchenjansen756211 жыл бұрын
this was both educational and strangely adorable, thank you!!
@ohnoitsjasmin8 жыл бұрын
The cause is really more the intrinsic brightness of the objects we see and how far away they are. As light from distant objects gets to earth, it gets dispersed and becomes less bright by a factor of the radius squared. So, we can only see objects within our galaxy (and the Andromeda Galaxy and Magellanic Clouds, if you're in the southern hemisphere). Bringing up redshift isnt relevant for objects within our own galaxy. *Because* they're within our galaxy... But nothing within our own galaxy is getting redshifted enough to become infrared. And, Andromeda is actually moving towards us
@jeanmessias7 жыл бұрын
Amazing!
@emmettdonavan949 жыл бұрын
Ok for all of the religious people ranting about how disrespectful us atheists are, i just want you to know that it is very disrespectful for you to yell at us and make fun of our beliefs and point of view. We have the right to believe what we think is the truth and you also have the right to try to convert us to your religion but the best way to do that isn't by calling us names and telling us we are ignorant because frankly im doing very well in my life without believing in any higher power
@MahboobAliKhan10 жыл бұрын
When stars ,galaxies moves away from us they are into red shift and the farther they move the more infrared they become below visible spectrum,therefore the sky in the night appears dark,even though there are so many stars.
@BlaseFawn3857 жыл бұрын
This is a beautiful concept--this idea of light we can't see.
@coachfresh111 жыл бұрын
Reading the comments will help shed some light on the subject...choose wisely though...
@imconfusedtwo9268 Жыл бұрын
Bravo, easy to understand 👏. Old saying, if you can't explain it to a child you don't understand it yourself.
@GUSRULZ44511 жыл бұрын
More to do with the fact that as things get further away, the light emitted (or reflected) from anything, regardless of how big it is, spread out as the distance between us and 'it' increases exponentially (Google inverse square law). This is why things can seem brighter than others, when in reality, they're just closer. But you already knew that..... Asteroids etc are so sparse and photons so small, it's unlikely the two interact at all on the journey from there to here.
@nazcov10 жыл бұрын
3:29 - We've shed some light...
@bhoovJunc8 жыл бұрын
I think it's because we are "evolve" to see specific light wavelengths which are from red to violet. I mean all of human ancestor who can see infrared or ultraviolet will suffer the disadvantages of bright night including discomfort to rest. So they must adapt the situation or their ability to survive reduced. I also think the theory of natural selection can apply the same way.
@gooseberry_disliker3 жыл бұрын
this is one of the best explanations i've come across.
@moritzl70658 жыл бұрын
This video should be called: "Olbers' paradox explained". Its pretty much the same thing.
@abhishekshah118 жыл бұрын
Actually Kepler thought about it first.
@seok7928 Жыл бұрын
great summary for Olbers' paradox
@moiquiregardevideo7 жыл бұрын
On the radio wave point of view, the sky is kind of dark gray. The cosmic background is in every direction. That seems to indicate that the universe goes on at infinity. On the other hand, the signature of hydrogen, red shifted below the infrared frequency, and below tera-hertz, seems to stop at a specific radio frequency in the giga-hertz range. If I am not mistaken, this is actually the only reason we compute the age of big bang as 13 billion years.
@Poulpink8 жыл бұрын
Very nice, I've always been wondering at this question and this perfectly explains it
@mjf71200011 жыл бұрын
Who ever did the work with the marker is very talented and I enjoyed this video largely due to it. Well done.
@smorgastartan791311 жыл бұрын
the guy with the marker is the guy talking aka henry
@Antonmunnik1511 жыл бұрын
I just want to clarify to those who noticed... the dopler effect; the change in frequency of a wave with a moving source thereby slowing or speeding up the cats meow on a passing train. the dopler effect of light (as light has a constant velocity regardless of source) is a little different than the dopler effect of sound. Same name same result different process.
@CoryAllenThePerson9 жыл бұрын
Or it could just be that the inverse square law of light makes stars at greater distances undetectable to our naked eyes because of how much their energy falls off.
@Waterfront9753 жыл бұрын
If energy can be either electromagnetic waves or matter by E=mc2 then light should be able to be transformed to matter, then the sky does not have to light up. Also if I am not mistaken, atoms can have different energies and emit and receive photons and also combine with other atoms to create molecules with higher or less combined energy.
@bormisha10 жыл бұрын
Omg, I never thought about it before despite being a physicist. Indeed, it's a super curious problem to think about.
@Petch85 Жыл бұрын
This is one of my favorit videos on youtube. I love it so much.😍
@Pyrovis11 жыл бұрын
I'm not 100% sure on this, but i think that because they're moving away from us, the light wavelengths get longer which pushes them to the red side and to the infrared side of the colour spectrum.
@icecreamman133711 жыл бұрын
the greater the distance between points in the universe, the faster they are moving away from each other due to universal expansion, thus a greater redshift effect. simply put, the universe's 'size' (for lack of a better term) is much bigger than that of the distance between the sun and earth, so the universal expansion is the same everywhere, but objects that are further away from each other 'expand' away from each other faster than objects that are close to one another.
@alfahim9iner9 жыл бұрын
One of my favorite videos
@WJames-nq2df6 жыл бұрын
It's pretty humbling to look up at a distant star knowing that it's already gone supernova and the gasses have dissipated hundreds of thousands of years ago but you're stil there looking at it as if it's still floating around the universe. It's death may never be seen by any human but we're the only ones to see that star while it lived.
@UTUBESUCK66611 жыл бұрын
The actual answer is the human eye can only perceive a very small, narrow band of the electromagnetic spectrum called "the visible spectrum". We are basically "blind' for every wave length above and below the visible spectrum. Those wavelength are usually expressed in nanometers (nm). Our eyes can only "detect" light with wavelength between 390 and 700 nm, but the entire spectrum span a mind boggling 10^-21 nm (gamma rays) to 1 million nm (infra red) !!
@mercybellafiore367710 жыл бұрын
I can listen to your voice all day... You have great information in your videos, and since I have synethesia, your voice smells like the beach. And I love the beach.