The Big Bang: Crash Course Astronomy #42

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Thanks to observations of galaxy redshifts, we can tell that the universe is EXPANDING! Knowing that the universe is expanding and how quickly its expanding also allows us to run the clock backwards 14 billion years to the way the universe began – with a bang.

Crash Course Astronomy Poster:

Table of Contents
Distant Galaxies Show a Red Shift in Their Spectra 2:07
The Universe is Expanding 2:51
This Model is Called “The Big Bang” 5:12
The Universe is Almost 14 Billion Years Old 11:43

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Hubble Goes to the eXtreme to Assemble Farthest-Ever View of the Universe [credit: NASA; ESA; G. Illingworth, D. Magee, and P. Oesch, University of California, Santa Cruz; R. Bouwens, Leiden University; and the HUDF09 Team]
Out of this whirl: The Whirlpool Galaxy (M51) and companion galaxy [credit: NASA, ESA, S. Beckwith (STScI), and The Hubble Heritage Team STScI/AURA)]
Red-Shifts in the Spectra of Extra-glactic Nebuale….83…10H&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf [credit: American Astronomical Society, NASA Astrophysics Data System]
Andromeda [credit: Bill Schoening, Vanessa Harvey/REU program/NOAO/AURA/NSF]
The Big Bang (video) [credit: NASA]
The Sun [credit: NASA/SDO]
Alpha Centauri [credit: ESO/Digitized Sky Survey 2, Acknowledgement: Davide De Martin]
Andromeda [credit: NASA/JPL-Caltech]
Friedmann Universes
Friedmann Equation
Penzias and Wilson stand at the 15 meter Holmdel Horn Antenna that brought their most notable discovery.,_New_Jersey.jpeg [credit: NASA]
Planck CMB [credit: ESA and the Planck Collaboration]
Galaxy Superclusters [credit: Marenostrum Numerical Cosmology Project]


The Reasonable Gamer says:

If the space is what is actually expanding, and the galaxies are not actually moving, then does that mean that we are technically still inside the "explosion" of the Big Bang?

pixelfizz says:

Anyone else get these weird moments where you suddenly realise you're actually alive and you're like "WHAT THE FUCK IS ALL THIS?????" I get that a lot lately….

Rosette Granados says:

This was uploaded yesterday. Perfect timing for my final. Thank you.

Tushar chaudhary says:

the funny thing is that intelligent people always stay in doubt. whereas dumbass religious people always try to shout on top of their lungs claiming their religion to be correct!

Brucifer says:

The flying spaghetti monster gag was fukin priceless.

Ebon Hawk says:

''there is nothing for the universe to expand into ect''
no, we have no knowledge of anything outside our universe, doesn't mean there is something.
saying there is nothing, is as truthful as saying ''beyond the edge of the universe there will be bananas and chocolate''

don't say something is a fact when it's unproven.
say it more like ''it is unanimously believed that there is nothing beyond our universe''
otherwise you're spreading misinformation.

Leonor Diaz says:

My astronomy professor used to explain the expansion of space this way: imagine you're baking a blueberry muffin. When you add the batter with the blueberries in the cupcake liners, the blueberries are in certain places. After baking, because the batter has cooked and expanded, the blueberries have also moved with it, but only because the batter took them along for the ride.

Isaac Andrade says:

Oh, the flame war about the existence of everything… Shouldn't we focus on learning more instead of feeding that stupid flame?

Great video though, and it being the #42 of the series man… just pure awesomeness!

Nillie says:

13.82 Gigayears!

Riccardo Bove says:

Does this mean that the space inside us is expanding as well? So we're basically giants compared to before? :D

Firdaush Bhadha says:

So I have a question: People often say there is no centre to the universe. However, do they mean "our" visible universe or the universe in its entirety (other dimension and all). Why I ask is because if our 3 dimension "reality" exists as a hologram on the outside of a "bubble" universe then indeed there is no "centre" to it. However, technically there is "core". Being able to perceive the other dimensions we would be able to look inward. If you imagine 2D perceiving people in a universe where people lived on the outside of a 3D universe, there would be no up and down, to them the universe has no centre because it is infinitely flat. HOWEVER, if they could some how look down or go down then they could. Hence our down and centre may be the "big bang" it self. That would be the centre of our universe because if we were to go to that centre the universe would be just forming and time would be a dimension.

I hope my question is clear.

iamihop says:

Not all observable galaxies are moving away from us. Just the ones far enough away for gravity to be unimportant.

natnew32 says:

…no explanation of what it actually was?

crowbringer says:

Unless it's a quantum simulation!

babis8142 says:

I'm going to miss this show

Arthur Piot says:

also, the big bang is when time began so scientifically speaking you can't say "before the big bang" because that's when time began existing

Cameron Miller-DeSart says:

What are the names of the equations listed in the video?

no more trolling says:

I've been brain-fucked again!

Wymetime says:

Lol. Flying Spaghetti Monster cameo.

a40989d1 says:

It was distasteful to mock religion (With the spaghetti monster). Just leave religion out of it and talk about science. They are 2 different things, no need to mock one or the other.

Forrest Rittmann says:

Got it: no center, but a start time, pretty simple. ( just kidding, great as always!)

KatsKradleXX says:

How can we determine the difference between past speed and current speed of a faraway galaxy? In other words, the way this is being explained, it seems like you could interpret the redshift findings to mean that distant galaxies (which we see in the past) had BEEN moving away from us faster than close galaxies. How has it been determined that those distant galaxies are still currently moving at that speed? I think there must be something in how redshifted light is detected that I don't understand, if someone cares to explain. 

mchapra says:

One day I will find a science video about this stuff that doesn't take a jab at religion and just focuses on teaching the subject at hand.

I get it, and I know, religion is bad for progress yadda yadda whatever I don't care. I just want to learn, not be part of your weird crusade against people who want to be willingly ignorant. Thanks. Keep your garbage to yourselves and focus on actually teaching next time.

Dêstynatiõn Y says:

What a lie, unbelievable, I suppose I will be obligated to ignore this mini series.

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