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  • If you collect everything there is in the universe, (wow that’d be a lot of stuff)

  • but what color would it be?

  • It isn’t possible to answer that, but we can at least go back in time far enough to

  • see how it looked when it all began to exist.

  • Yes, this is apparently possible.

  • We all know about this mysterious and fascinating moment called the Big Bang, which gave birth

  • to all that we can see around us right now.

  • Now containing red dwarfs, white dwarfs, seven dwarfs, emerald supernovas, blindingly bright

  • quasars and everything in betweenthe Universe is as colorful as it gets.

  • But of course, it wasn’t like that at the time of its birth.

  • It originally had just one color.

  • As it expanded and cooled down, it formed more and more tangible matter and started

  • to morph into all the colors were used to seeing today.

  • To be able to see through time to the very first moment 13.8 billion years ago -- I wasn’t

  • around then -- you would need a time machine!

  • But even then, you won’t see anything.

  • Just black nothing.

  • And it’s not like the clocks on your time machine are offthis is the moment the

  • Big Bang is happening.

  • You just can’t see it because our eyes are sensitive to photons, and none of them exist

  • at this point.

  • The universe is simply too hot now to allow even something as basic as photons to form.

  • But seconds laterit’s already a different story.

  • During these first seconds, the universe is expanding so fast and with such power that

  • the temperature drops by trillions and trillions of degrees before it reaches the end of the

  • first minute of its life.

  • Approximately 14 seconds from the beginning, it’s already at 5 and a half billion kelvins,

  • and 48 seconds later it loses another 3 and a half billion degrees.

  • If, from the sheer epic of this universal scale, these numbers sound humble to you,

  • that’s my faulttheyre anything but humble.

  • And the best proof of that would be that you can’t see anything at all.

  • How is that?

  • Well, photons already exist, in fact, as well as protons and neutrons; Moronswell

  • talk about some other time -- cand theyre already busy forming the various nuclei of

  • gases like helium and hydrogen.

  • Congratulations, by the way: these gases give us our first forms of tangible matter!

  • And when gas is heated up like that, itll take the form of plasma.

  • Everything is a blazing plasma right now, and that’s bad news for photons because

  • they can’t move freely in such extreme environments.

  • And if photons can’t move how they want, you won’t be able to see anything.

  • To see something, youll have to wait; and not another minute, but another 380,000 years,

  • when the universe cools down.

  • Until then, this epoch in the history of everything is what scientists refer to asThe Dark

  • Age”.

  • And while our time machine is reconfiguring, let’s figure out how scientists even know

  • all this if they don’t have a secret time machine like this one.

  • They use a method called cosmic microwave background scanning.

  • That moment, 380,000 years after the initial Big Bang, the universe got so hot that subtle

  • traces of that heat and light still persist in the space around us.

  • They form an imprint, which shows the whole process of the universe’s creation.

  • Scientists learned to study this imprint like an ancient map of a world that no longer exists.

  • Fun fact: astronomers figured out that the age of the universe is exactly 13.8 billion

  • years because they can see this imprint from a distance as huge as 13.8 billion light-years

  • away.

  • But remember, at the time were talking about, (380,000 years after the Big Bang)

  • the universe was still quite small.

  • That’s if you can call something like 84 million light-years across small.

  • But in comparisonyes, it’s 164 times smaller than the universe we know now.

  • And it wasn’t all plasma anymore.

  • Finally, photons were given the green light (ha thegreenlight!) to move wherever

  • they want and that means that we can see something here.

  • And that something is a colossal blob of blindingly bright light.

  • You wouldn’t be able to clearly make out anything, actually, because the color of everything

  • is dictated by the temperature alone.

  • This phenomenon is also sometimes called blackbody radiation.

  • This radiation is as bright as the matter it irradiates is hot.

  • And the term blackbody doesn’t mean that whatever emits this colorful thermal radiation

  • is necessarily black per se.

  • It means that this irradiating object is unreflective to light.

  • Or at least its own appearance, including its color, won’t mean much to an observer

  • because of this radiation that obscures everything.

  • To draw a picture of it in your mind, remember how lava looks.

  • It’s red, yellow and orange glow isn’t representative of the matter itself, because

  • in places where it already cooled down, it’s ashy black or grey.

  • But of course, you would say that lava is bright in its fiery colors.

  • This is how the whole universe looked back then, 380,000 years after the moment it was

  • born.

  • It looked like fire because the temperature made it look that way.

  • As the universe continued to expand, it also continued to lose the heat.

  • This process is in action to this very day, and scientists say that it won’t stop any

  • time soon; possibly not even until the universe consists of mostly nothingness between celestial

  • bodies, and its temperature will be a tiny bit higher than absolute zero.

  • You can even imagine it like one supernova explosion so massive that it takes billions

  • of years to happen.

  • And fascinatingly enough, we happen to live somewhere around the middle of its timeline.

  • With the loss of temperature, the glow of its thermal radiation has gone through several

  • metamorphose.

  • From blindingly bright yellow, it went to fiery orange and then became red, which was

  • replaced by black.

  • Mostly.

  • These relatively modern times in the life of the universe became the dawn of its spring,

  • as more and more stars emerged from the cooling matter.

  • They were born from hot gas clouds, and they were aging, cooling, turning orange, and then

  • red as the universe did before.

  • Then the stars were exploding into supernovas with every color imaginable; or collapsing

  • into black holes, where no color is possible at all.

  • Fun fact, black holes are what scientists call perfect black bodies, and they emit radiation

  • powerful enough to be seen as a ring of orange heat.

  • If you remember the first photos of a black hole that came out recently, this is what

  • you saw on them in the most basic terms.

  • In some way, asking about the color of the universe during the Big Bang is like asking

  • about the color of a black hole.

  • The first and only visible thing that ever appeared in the universe was so heated that

  • it looked like an orange glow and nothing more.

  • Today it’s another matter completely.

  • There are from 100 billion to 200 billion galaxies around us and theyre all full

  • of motion, so colors are uncountable and everchanging.

  • When ancient astronomers looked into the skies and saw part of our own galaxy, the Milky

  • Way, they didn’t name it this just for kicks.

  • They meant it: it looked as if someone had spilled milk over the dark skies.

  • And one of them thought: What a great name for a candy bar!

  • The other ancient astronomers asked: What’s a candy bar?

  • Anyway, there’s one rough estimation about what color the universe is today.

  • It’s well known that our galaxy isn’t that dense, and its appearance to us is only

  • what were limited to from our planet’s perspective.

  • Yet this perspective matters because it blurs all stars, and all matter in general, into

  • something homogenous.

  • And this is the key to knowing what colors a galaxy, or even the universe, would be if

  • it was just one separate object.

  • And the answer is probably in your cup every morning.

  • This color is Cosmic Latte.

  • And the analogy between the universe and coffee is a surprisingly good one.

  • Just like a good latte, the universe will get darker with time and it is the lightest

  • and brightest right after it was made; or appeared, in the case of the universe.

  • Um, I’d like a low-fat, no-foam, de-caf double shot universe please, and hold the

  • whip.

  • Hey, if you learned something new today, then give the video a like and share it with a

  • friend!

  • And here are some other cool videos I think you'll enjoy.

  • Just click to the left or right, and stay on the Bright Side of life!

If you collect everything there is in the universe, (wow that’d be a lot of stuff)

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