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Current time:0:00Total duration:11:02

Video transcript

the purpose of this video is to just begin to appreciate how vast and enormous the universe is and frankly our brains really can't grasp it but we'll see in this videos we can't even grasp things that are actually super small compared to the size of the universe and we actually don't even know what the entire size of the universe is but with that said let's actually just try to appreciate how small we are so this is me right over here I am I am 5 foot 9 inches depending on whether I'm wearing shoes maybe 5 foot 10 with shoes but for the sake of this video let's just roughly approximate around 6 feet or around roughly I'm not going to go into the details of the math around 2 meters now if you mul to 5 where to lie down 10 times in a row you'd get about the length of an 18-wheeler it's about 60 feet long so this is times 10 now if you were to put a 18-wheeler on kind of if you were to if you were to make it tall as opposed to long somehow stand it up and you were to do that 10 times in a row you'll get to the height of roughly a 60-story skyscraper so once again if you took me and you piled me up 100 times you'll get about a 60 story skyscraper now if you took that skyscraper and if you were to lie it down 10 times in a row you'd get something of the length of the Golden Gate Bridge and once again I'm not giving you the exact numbers it's not always going to be exactly 10 but we're now getting to about something that's a little on the order of a mile long so the Golden Gate Bridge is actually longer than a mile but if you go within the twin spans it's roughly about a mile it's actually a little longer than that but that gives you a sense of a mile now if you multiply that by 10 you get to the size of a large city and this right here is a satellite photograph of San Francisco this is the actual Golden Gate Bridge here and when I copy and pasted this picture I tried to make it roughly 10 miles by 10 miles just so you appreciate the scale and what's interesting here and this picture is interesting because this is this is the first time we can kind of relate to cities but when you look at a city on this scale it's starting to get larger than what we're used to processing processing on a daily basis this a bridge we've been on a bridge we know the bridge looks like we know that a bridge is huge but it doesn't feel like something that we can't comprehend already a city is something that we can't kind of comprehend all at once we can drive across the city we can look at satellite imagery but this is you know if I were to show a human on this it would be unbelievably unbelievably small you wouldn't you wouldn't actually be able to see it would be less than a pixel on this image a house is less than a pixel on this image but let's keep multiplying by ten if you get multiplied by ten again you get to something roughly the size of the San Francisco Bay Area this whole square over here is roughly that square right over there let's multiply by ten again by ten so this square is about a hundred miles by 100 miles so this one would be about a thousand miles by a thousand miles and now you're including all of a lot a big part of the western United States you have California here you have Nevada here you have Arizona and New Mexico so a big chunk of a big continent we're already including and frankly this is beyond the scale that we're used to operating we've seen map so maybe we're a little used to it but if you ever had to walk across this type of distance it would take you a while to some degree the fact that planes go so fast almost unimaginably fast for us that it's it's made it feel like things like continents aren't as big because you can fly across them in five or six hours but these are already huge huge huge distances but once again you take this square that's about a thousand miles by a thousand miles and you multiply that by 10 and you get sucked you get pretty close a little bit over the diameter of the earth a little bit over the diameter of the earth but once again we're on the earth we kind of relate to the earth if you if you if you look carefully at the horizon you might see a little bit of a curvature especially if you were to get into the plane so you can you can even though this is frankly larger than my brain can really grasp we can kind of relate to the earth now you multiply the diameter of Earth times 10 and you get to the diameter of Jupiter and so if you were to sit earth right next to Jupiter obviously they're they're nowhere near that close that would destroy both both of the planets actually would definitely destroy Earth it would probably just kind of just be merged into Jupiter earth so if you put earth next to but it would look something like it would look something like that right over there so I would say the Jupiter is definitely all you went on this kind of diagram that I'm drawing here it's definitely the first thing that I have I really I can't comprehend I mean you know it's it the earth itself is so vastly huge Jupiter is it's ten times bigger in diameter it's much more it's much larger in terms of mass and volume and all the rest but just in terms of diameter it is ten times bigger but let's keep going ten times Jupiter gets us to the Sun this is times 10 so if this is the Sun and if I were to draw Jupiter it would look something like I'll do Drupa tur and pink Jupiter would be around that big and then the earth would be around that big if you were to put them all next to each other so the Sun once again is huge even though we see it almost every day it is unimaginably huge even the earth is kind of unimaginably huge and the Sun is that much is a hundred times more unimaginably bigger now we're going to start getting really really really wacky you multiply the diameter of the earth of the Sun which is already a hundred times the diameter of the earth you multiply that times 100 and that is the distance from the earth to the Sun so I've done my I've done this I've drawn the Sun here's a little pixel and I didn't even draw the earth as a pixel because the pixel would be way too large we would have to be a hundredth of a pixel in order to draw the earth properly so this is a unbelievable distance that between the earth and the Sun it's a hundred times the distance of the Sun of the diameter of the Sun itself so it's massive massive but once again these things are relatively close compared to where we're about to go because if we want to get to the nearest star so remember the Sun is a hundred times the diameter of the earth the distance between the Sun and the earth is a hundred times that or you could say it's it's ten thousand times the diameter of the earth so these are unimaginable distances but to get to the nearest star which is 4.2 light-years away it's too 200,000 times and once again unimaginable it's 200 thousand times the distance between the Earth and the Sun and to give you a rough sense of how how far apart these things are if you if the Sun was roughly the size of a basketball if the average star was about the size of a basketball and our part of the galaxy in a volume the size of the earth so if you had just like a big volume the size of the earth if the stars were the sizes of basketballs and our part of the galaxy you would only have a handful of basketballs per that volume so unbelievably sparse even though the galaxy looks like even though when you look at the galaxy and this is just an artist's depiction of it it looks like something that has you know kind of the spray of stars and it looks reasonably dense there is actually a huge amount of space that most the the great-great-great-great-great majority of the volume in the galaxy is just empty empty space there and there's there's there's no stars no planets no nothing I mean this this is a huge jump that I'm talking about and then if you really want to realize how large a galaxy itself can be you take this distance between the Sun or between our solar system in the nearest star so that's that's 200,000 times the distance between the Earth and the Sun and you multiply that distance by 25,000 so if the if the if the Sun if the Sun is right here our nearest star will be in that same pixel they'll actually be within I mean you know you'd have to get a ton of stars within that one pixel even though they're so far apart and then this whole thing is a hundred thousand light years it's twenty-five thousand times the distance but then the distance between the Sun and the nearest star so we're talking about unimaginable unfathomable distances just for a galaxy and now we're going to get our you know frankly my brain is already you know it's already well beyond anything that it can really process at this point it almost just becomes abstract you know thinking it just becomes playing with numbers and Mattox but to get a sense of the universe itself the observable universe so we have to be clear because we can only observe light that started leaving from its source 13.7 billion years ago because that's how old the universe is the observable universe is about 93 billion light years across and the reason why it's larger than 13.7 billion is that the light the things the points in space that emitted light 13.7 billion years ago those have been going away from us so now they're on the order of 40 billion light years away but just this isn't about cosmology this is just about scale and appreciating how huge the universe is just in the part of the universe that we can theoretically observe that we can theoretically observe it would have to you have to get and that we can observe just because we're getting we're getting of we're getting electromagnetic radiation from those parts of the universe you would have to multiply this number so let me make this clear 100,000 light years that's the diameter of the Milky Way so 100,000 light years that's the diameter of the Milky Way you would have to multiply it not by a thousand a thousand would get you to 100 100 million light-years all right this is a hundred thousand times a thousand is a 100 million you have to multiply by a thousand again by a thousand again to get to 100 billion light years and the universe for all we know might be much much much much larger it might even be infinite who knows but to get from just the diameter of the of them of the Milky Way to the observable universe you have to multiply by a million and already this is an unfathomable distance so in the whole scheme of things and the whole scheme of things not only not only are we pretty small and not only are the things we build pretty small and not only are is our planet ultra small and not only is our is our Sun ultra small and our solar system ultra small but our galaxy is really nothing compared to the vastness of the universe