Added: 1 year ago
From: khanacademy
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  • Sort of makes you feel insignificant, but then again those stars, planets, galaxies, the Universe has basically been doing what it's been doing for the last billion years. Stars don't calculate how far they are from another star. Light doesn't know how fast it's traveling. The next galaxy over doesn't know when it will collide with ours. So, in that perspective we are not insignificant at all for we can do what the Universe cannot.

  • never questioned this before but if night sky is mostly if not all milky way, how can we see andromeda? i dont understand how good telescopes are but even some of these distances seem crazy for a telescope let alone andromeda

  • @kyleag9 We can see other galaxies because 1. The stars are so far away from each other that they are not blocking the view and 2. The light that travels from the galaxies are in a vacuum, and is therefore not blocked by anything either.

  • I am going to do myself a favour and ignore the religious comments because they tend to bring my piss to a boil...

    It is astounding how immensly vast a single galaxy is, not to mention when you cound that there are roughly 100 billion galaxies like our own dispersed in a visible universe which is around 90 billion light years in diameter.

    Now go read about the multiverse theories...

  • How can all this just exist by it self ?

  • @aimalkhan123 crazy init...

  • @davefk the black hole is in the centre and its sucking in stars dust etc so its all condensed in that area. they say there are suns orbiting the black hole traveling over 1,000,000mph. great video btw love it when its put in perspective. makes you feel so insignificent. lol

  • What makes the center of a galaxy so bright if it is a black hole?

  • It`s not that the Universe is so big , it`s just that we are all so small !!!!!!!!!!

  • when he said the grain of sand and the football field.. did he mean the football field is the galaxy not universe?

  • If I remember correctly 1 light year is 5.8 trillion km.

  • This is a confirmation that science has proved god exists.

  • The stunned enthusiasm of your delivery is adorable and entirely justified.

  • go to 7:25 and he stutters so much!

  • What this video shows in other words is that interstellar travels are an impossibility, at least with our present and foreseeable technologies.

  • @237Michael wormholes allow travel over great distances to take seconds.

    the technology is there, its all theoretical but its there.

  • It was God.

  • 1 person disliked this video. I dont fully blame him, i can barely believe this either.

  • i feel tiny :(

  • Another thing is, even though we are so incredibly tiny in galactic terms, we're still incredibly huge compared to stuff like atoms. Its really incredible how extreme scales and sizes in universe are.

  • What the most amazing thing is that looking up at the sky you look into the past. Every single star (or light coming from the star) that we see, we see as it was in the past, very distant past. And looking pictures or other galaxies or pictures like deep field is just absolutely amazing. Knowing that right now, at this moment, there are trillions and trillions of other planets out there, with billions of creatures and different life forms on them..most of whom wonder if they're alone...

  • yeah and all this was made and put into perfect balance by chance right? *sarcastic Laugh*

  • Gods fake get fucking over it.

  • @INMATE2468 Well you do seem like a very smart individual, judging from your great grammar use. I guess all of us have no option, other than to take your word for it. Thank you kind stranger, for explaining to me how I'm supposed to live the rest of my life! And such a nice way of putting it by the way. I hope you have a great day :)

  • mind officially boggled, good lord. Can't wait till hyperspace...

  • Maybe you should be more specific, There are less solar systems then there are stars because there are sometimes multiple stars per system.

  • there is a smaller star closer to our solar system about a half inch on screen to the tp left.

  • 11:10 i think you meant our galaxy as a hole, not the universe

  • Universe is Science. God shall never be included in the discussion.

  • @niconikko wrong

  • @msms47 How so.

  • @MrBazingafy becaus god made science or u can say that god is sicence

  • @msms47 Why, though. Don't just make baseless claims.

  • @niconikko God is the creator of the universe and everything in it.

  • @niconikko can science create a universe ? science is about knowing the universe and its mysteries.. not creating it.

  • @niconikko it depends on what you consider god.. because somethimes may have nothing to do with religion...

    you can simply say, nature is a god... a true god a true criator... but not in religious terms...

  • @niconikko Science discover, God creates.

  • SubhanAllah God is The Creator of all things. He is OUTSIDE of his own creation(including the concept of time) Imagine how big HE is!!! Yet people remain arrogant ....

  • I mean the stars are not equal distant from each other as they were thousands of years ago. The night sky would look completely different in thousands of years wouldnt it? The scientists must pick a specific date so all stars are in the same time zone to get an accurate image.

  • When scientists depict the image of our galaxy like the one in this video, do they calclulate where they are now by calculating their trajectory or use the images they recieve of them of where they were thousands of years ago??

  • I seriously think there are more beings out there for two reasons...

    1) Why would God use all his abilities just to make a nice pretty multiverse for us to look at?

    2) What did Jesus Christ say? "I have sheep that are not of this pen"

    Makes you wonder how our creator could make so many different beings each with their own personality and thoughts. Genesis is definatly an interesting read :)

  • @PhilipK100 God didn't create the Universe

  • @TheAppleShampoo182 hahahahahah wow your stupid

  • DAMN! srry forgive my language but its true! Is our sun rotating and circling around the center of the milky way?

  • 80,000 years to Alpha C! Imagine, by that time we would be a different species!

  • I think NASA knows SO MUCH MORE and they're not telling us. :(

  • one guy missed

  • so every star has a solar system with planets? wikipedia says there are six million solar systems with planets and 200-400 billion stars.

  • Sal, as I understand it, the main reason we don't have much information on the opposite side of the galaxy is because from our perspective you can't measure the blue/red shift of objects, since they are moving horizontally. I don't think the center of the galaxy being in the way has much to do with it.

  • Kind of gives you an idea on how insignificant we are.

  • @jpr422

    No, we are not insignificant. The Universe, et.al; may be large but that doesn't make mankind not count for something.

    The entire Universe and God and Whatever has failed to explain itself / him-or-her self to everyone's satisfaction, so we are out there looking.

    We are small relative to the Universe or God or Whatever yes, but we are not insignificant.

  • @blardosplats Are you talking in terms of our impact on the universe (or our understanding of it) and the world we live in?

  • @jpr422 

    Yes.

  • Finally,someone that explains clearly the questions I raised in the 9th grade. My geography teacher was pretty much bored and could not wait to go for her coffee break,rather then sit down and explain.That was the main reason why I choose history over geography,I was fascinated about the stars, universe, and so on,but yeah..many teachers could not care less about what the student would like to learn...at least now after some years,I can pick up where I left off.

  • It's just Literally Unthinkable.... Our TINY little brain would blow up if it ever tried to "get the picture"... Great video. Tnx

  • anutha great video :}

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  • Even after finishing this video, it takes couple of minutes to response....Simply there is no word to describe the size of this universe. What the hell!

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  • This is AMAZING!

    I'm watching the whole "scale" series that your posting :D

    very interesting and mind blowing

  • Sal, thanks for loading these up with scale comparisons and analogies. We are not equipped to appreciate the massively large and super-small without analogy. I wish you could bring a 3D animator onboard at the Khan Academy to assist with presentations like this (better visuals in this case would really serve to strengthen analogies and provide a nice smooth transition from one scale to the next.) Great stuff!

  • did you mean to say that the grain of sand would be in comparison to the galaxy or the universe. I assume you meant galaxy??

  • 7:27 his mind blew up LOL

  • Sal, you would be one of the most interesting people I can think of to talk to.

  • with all due respect when you say life has not been observed, we firstly have observed an UNIMAGINABLY small portion of the universe. this being said, considering the universe is in fact infinite i honestly think it is not only ignorant to assume we are the most advanced civilization in what we understand the universe to be. Do not get me wrong i am a firm believer in god but i also know that judging by pure odds life is abundant. 

  • “By Heaven with its oscillating orbits” (Qu'ran Surat adh-Dhariyat, 7)

  • And it is We Who have constructed the heaven with might, and it is We Who are steadily expanding it. (Qur'an, 51:47)

  • ERROR: At 11:05 you compared the Oort cloud with the size of the Universe, you clearly meant the Galaxy hence 1mm ~ 100m.

    If the Oort cloud = 1 light year = 1mm in diameter, and the visible Universe is 13.7 billion light years in radius (27.4 billion light year diameter), then on that scale the visible Universe would be 17,029 miles wide (2.1 times the diameter of Earth.

  • why is this not in high school curriculum?

    this should be basic science knowledge

  • @007SPIDER007

    School is designed to make good workers, not to be interesting.

  • @9:05 Supermassive Black Hoooole!

  • why r u guys fighting aliens have a high percentage of existence there LOL

  • @DrFHead What hypocrisy dude? What the fuck are you talking about? I don't believe in alien life, I said that in my post. I believe in the possibility of alien life, which is something that many staunchly deny. You don't look like an ass, you are an ass, making up arguments without any reason whatsoever. I get it dude, you are one of those stubborn anti-aliens who don't even ponder about the possibility of their existence. If you felt insulted by my post, suck it up for being so narrow minded.

  • @DrFHead Nowhere in my post did I "authoritatively claim" there has to be intelligent life, especially without any proof. My criticism went to those who staunchly deny it, nothing more, nothing less. I do not believe in alien intelligent life, I believe in the possibility of its existence given the size of the Universe. Save your rant when it actually makes sense. Here you just ended up looking like a stupid ass.

  • This video really reminds me of the short movie: "Powers of Ten" which talks about relative sizes and distances in the universe like this khanacademy video. You guys should really Powers of Ten, thumbs up so people know. =D

  • Great work sal I havn't watched any of your videos in a long time, but from watching these i'll make sure I check in more frequently =) , now you just need to explain the very small and most people will be set. Imagining a hydrogen atom as 1380000000000000000000 times smaller than a grain of sand is simply too difficult for me :( .

  • Thank you, Sal! This is so awesome. Love astronomy,can listen to this stuff forever.....!!!!

  • Khan makes me love learning :D

  • Te only thing to say, Allaho Akbar, Subhaaan Allah the designer of this piece we know of the universe we at least know about its existence.

    And there are still people who worship their little brain.

  • This reminds me of the final scene of Men in Black

  • We're nothing, and we're just now starting to realize it.

  • Mind=Blown

  • @villagepunk Literally.... ***(x_x)***

  • Great vid - Thanks

    You'll be familiar with this way of putting it too....

    v=buqtdpuZxvk

  • So would you say that there's a quasar in the Milky Way?

  • even the biggest star is a tiny little grain of sand when it compares to a galaxy. and a galaxy is a tiny little grain of sand when it compares to the universe. and the universe is a tiny little grain of sand when it compares to _____.

  • very interesting, however i don't believe everything you said.

  • @postmarvi Thats not matter of a belief. Information presented here is a scientific FACT.

  • @postmarvi What is it in this video not to believe? 

  • i never thought god could create all this by himself !!!!!!!!!!!!!

  • @amcbirds Guess what, he probably didn't. There are very solid explanations about the origin of galaxies, solar systems, planets etc.. A God fills very little use.

  • NICE!!!!

  • And this is nothing compared to the rest of the universe, in which there are billions more galaxies

  • " I'm busy to contemplate infinity." (A yogis answer to the question, what he is doing all the time:)

  • THanks for this video. One of the greatest problems confronting young learners is the scales involved in space, the atomic scale and geologic time.

  • Thank you for this video.

  • This is so cool.

  • Sal, I was thinking about the size and distances of stars yesterday morning (and it was pretty coincidental that you posted these videos a few hours later) and there is one little thing you may want to consider (it may help in blowing your mind, I don't know). Earth is traveling about 30,000 km/s. If you were to move 30,000km/s it would take about 40 years to get to Alpha Centouri. 4.2 light years is VERY far, but we manage to travel this far throughout our life span!

  • @Melthornal Actually, the Earth only travels at around 30 km/s.

  • @maulcs Ah, thanks for the correction.

  • It's very frustrating to know that we won't be traveling to any other stars in our lifetimes. Or galaxies for that matter. Pisses me off.

  • this is so awesome!

  • yes

  • And there are still idiots out there that authoritatively declare we're the only intelligent life in the Universe. I can't think of a more underestimated and often misused word than "Universe". It's simply unfathomable, yet people refer to it way too lightly.

  • @Ikus13 They may be right. The only position you can really take regarding life is purely agnostic. I am inclined to think it likely there is life elsewhere, but, in the absence of evidence, all that can be said is "I don't know". For example, if the chances of life arising were less than one in "The number of stars in the universe", i.e, under ordinary circumstances, spontaneous abiogenesis would be considered impossible, then a universe of this size would be needed to make it happen once.

  • @ImposingSumo I'm not saying that is the case, just that circumstantial evidence can be presented for both sides. None of which proves anything.

  • @ImposingSumo Agnostic would be to say "I cannot know", not "I do not know".

  • @thisisnotanick I disagree. I am agnostic about whether the cheese in my fridge has gone off, in that I presently don't know. However, once I have evidence one way or the other, i.e. I check by smelling the cheese, then I have become a 'Gonstic', that is, I have the knowledge of the state of the cheese in my fridge. An Agnostic says "I don't know". He makes no claim as to whether that knowledge is ultimately attainable. To claim such a thing would be to claim knowledge would it not?

  • @ImposingSumo this is correct. An agnostic does not lay claim to any knowledge, but an athiest is definitive in his or her's belief that "god does not exist"

  • @zackboomer No, atheism is the non-belief in a god, not the claim that there is no god. Theist means "one who believes in god" or "with god" and atheist means "not one who believes in god" or "not with god".That's all it is. No claim of no god is being made. Maybe you have heard atheists make the claim that there is no god, but that's not the same as atheism being that claim.

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  • @genobahamut1337 fair enough, but isn't "the position that there are no deities" saying concretely that "there is no god"?

  • @zackboomer As I said, it's not the position that there are no gods/deities. It is just simply not believing in them. Not believing does not mean believing against or that there are none. It means that you simply do not believe in them. It's like the ruling "not guilty" to borrow someone else's explanation. Not guilty doesn't mean innocent, it means that you don't have evidence to claim them to be guilty. Just the same, I have no reason to thing god is real. Doesn't mean I believe there is none.

  • @zackboomer Atheists doesn't either claim to have knowledge wherever God exists or not, an Atheist just lacks the belief in such a being.

    And regarding other life in the universe.. I am confident there is other lifeforms out there.. We have only examined ONE life suitable (based on how life on earth works) and that very planet is sparking with life.. Imagine that there are trillion upon trillion of other planets out there.

  • @zackboomer I don't know any atheists that would claim that. Atheism is, in a nutshell: "In the absence of evidence to support this supernatural theistic claim, I don't believe. If evidence is presented, I will change my belief".

  • @Ikus13 for some people, ignorance is bliss

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  • @Ikus13

    You're right, and that intelligent life is called God

  • @stainermcbain so you're saying that what many millions of people call 'God' are simply aliens? Did nicholas cage star in a movie that depicted this?

  • @justinv3

    No, I'm saying that humans are not the only intelligent life in the universe. God is intelligent, and He is most certainly alive, although not really in a biological sense, because He is spirit. There is no good reason to believe in life on other planets, because life cannot spontaneously appear; it has never been observed, and is scientifically impossible.

  • @stainermcbain Dont you mean she?

  • @Ikus13 You need jesus mate.

    Jk.

  • @Ikus13 Look up Sumerian artifacts. They knew the planets went around the sun and talked about people coming from the sky.

  • @Ikus13 Do you know the odds of the right conditions for life to exist? Or life to evolve? Or a civilization species to evolve?

    Sure there are aliens, at this very moment, there is an alien civilization right now, unfortunately due to odds, it's 100 million galaxies away.

  • @Chnamanjx

    Recent studies that adjust the drake equation to what we presently know about our galaxy show that there could potentially be as many as 10 intelligent, broadcasting lifeforms in our galaxy alone.

  • @Chnamanjx

    Nonsense. Whilst I can agree that any life is likely to be well and truly beyond our reach - even if we somehow reach Light speed travel (which isn't that likely if all even possible) - your claim that they will be 100 million galaxies away is totally baseless. Which is because the odds of life to exist on a planet are relatively unknown.

    Those odds are always based on EARTH life, which has adapted TO EARTH. Therefore for other planets it could develop under different criteria.

  • @Chnamanjx

    And I'll go further to say that the number of planets within the habitable region (which is again generally restricted to what WE know as life, so the real region may widely contrast from what we think) is actually fairly high when you consider the sheer number of stars; it's even very likely there are many habitable planets of the right size in the right place, even within our galaxy. That doesn't guarantee life of course, but it does make your claimed odds nonsense.

  • @Ikus13 maybe they should say it in a Deeper Voice for Emphasis. Just so they don't sound like they're taking it for Granted.

  • @Ikus13

    Just because it's big and some call it 'Universal' doesn't mean that we aren't the only planet with intelligent life.

    Some people just want scientific proof.

  • @Ikus13 The evidence is what will ultimately be authoritative concerning intelligent life in other star systems. Have you ever heard of the Fermi Paradox? Its interesting to read about.

  • @Ikus13 Declaring that there is life in the galaxy is almost as bad as declaring that there is not. I'm am all for hypotheses, but making claims without evidence to back it up, is just ignorant.

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