Neil deGrasse Tyson Explains “The Sunset Illusion”
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- Опубликовано: 27 июл 2020
- In this StarTalk Radio explainer video, Neil deGrasse Tyson and comic co-host Chuck Nice are exploring what’s really going on when you watch those beautiful sunrises and sunsets.
To start, you’ll get a refresher on how the days of the week were named. Then, we discuss our pre-Copernican vocabulary to describe what’s going on in the sky. You’ll learn how refraction and our atmosphere impact sunrise and sunset. Neil tells us why, when you think you’re watching the sunset or sunrise, the sun is already past the point you're seeing. Neil also tells us how telescopes can calculate refractive effects when looking at stars.
Then, you’ll learn why the equinox is not actually the day where there’s an equal amount of night and day. Lastly, find out how light would interact with Earth if it were a black hole. All that, plus, Neil and Chuck discuss other “ghosts of the sky.”
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Science meets pop culture on StarTalk! Astrophysicist & Hayden Planetarium director Neil deGrasse Tyson, his comic co-hosts, guest celebrities & scientists discuss astronomy, physics, and everything else about life in the universe. Keep Looking Up!
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One of the coolest things I have ever experienced, is watching the sun set 4 times in one evening.
I was in my plane, watched the sun set started climbing hard, and the sun came back over the horizon, did it 3 times.
Thats awesome
Impossible ‘cause world’s flat 🙄🤣🤣🤣
Wow this is now something I need to experience
This can only happen if the sun is local and not in space 93,000,000 miles away.
@@YHWHSTRUTH88The opposite. The sunset was visible *again* when he climbed to a *higher elevation.* That only makes sense on a spherical earth with the sun going “down”.
Mom: Time to wake up, the sun has risen.
Me: Just wait five more minutes.
Bestt
So that's where that phrase came from 😄
… until the sun has REALLY risen!
Haha. That’s great!
Light takes approximately 8min to reach earth from sun so technically you're 3min late
I love the fact that Chuck is part of this show because he is the perfect proxy for the audience
We're not all comedians, you know. Only about 74%.
He sums up things very well
Chuck is not funny and tries waaaay too hard.
Wish I had him as a teacher!!! I could listen to him talk all day.
No matter how depressed I get, two minutes of Star Talk and I’m laughing.
its a great distraction
Yo guys, i just wanna say that u can overcome ur depression. U can do it guys.
Tyson better keep Chuck employed because he makes me laugh all the time.
You are a toilet human and a simpleton
@Flat Earth Data this is how you tag......also, what objectional reality is the technology you use to promote your incredulity based on? (Quantum mechanics) To answer your leading question, and cut your undoubtedly parroted response that should likely follow, as insults and arguments from emotion seems to be all that the #FlatEarth "community" is capable of, the answer is HORIZON. No the word horizon is NOT derived from HORIZONTAL. Level is a word, like most words in the English language, have a different meaning based on context. To calculate gravity you use the formula M1*M2/r^2. Any ball that is ON 🌎, will have a gravity that would be negligible. If we shrunk Earth down to the size of a basketball, it would collapse into a singularity from the sheer mass, but all of Earth's water could fit into a tea cup. Pour a teacup worth of water on a ball, adhesion alone should hold it. You have been tricked by a snake oil salesman, I hope you can stop trolling science and actually learn from it. #TrollingFE
Chuck is such a great co host. Watching him absorb these words of wisdom is a joy to behold.
@Flat Earth Data ermmmm... Curvature
@Flat Earth Data at sea level, about 3 miles
@Flat Earth Data Correct, they do not touch.
Chuck is a nice guy and very funny.
I cant help but feel that neil treats him like he knows nothing. Chuck knows a great deal.
Tyson is a brilliant educator, who understands illustrations, timing, the use of gestures, vocal modulation, etc, as valuable aids to teaching. He's worth watching and listening to carefully for those fine qualities.
Chuck makes a pretty good foil, reflecting the thoughts of a child who is learning from him. The humour doesn't quite translate internationally, but that doesn't matter so much, because Neil is busy teaching viewers and listeners in ways that they will remember the information.
The two of you make a good team.
Thanks for this video. It's the first one I've watched from this channel.🙂👍
When he said you could be seeing the light that was there billions of years ago gave literal chills
Man I love the chemistry between you two!
Me too 😁
They have a lot of chemistry for a physics show.
That's more like Gravitas 😅
Chuck literally called Neil “Babe” at the end.
@@theopminer952 Yess :D
I never liked Math in grade school. Never in high school. Somehow in my adult years I've grown to love and see just how COOL physics and Astro physics is lol
Exactly! I love science more when Neil teaches it.
I think two critical factors come into play. Firstly, a teacher who is interesting, engaged and genuinely enjoys teaching the content. Secondly, having a relevant topic or subject that you can relate the content to.
Because they never teach what is math & why we need to learn instead they shove hundreds of formulas to solve seemingly illogical problems for everyday life with extreme logic of math.
Rraviteja Mavr ,You Have To Start Out With 2X2,Before Being Able To Calculate Anything...Whether Its The Curvature Of The Earth,Or How Much Oxygen Do I Need For My Pt,On What Flow,and At What Rate..Need To Learn Math 1st,And If Your Science Teacher Didnt Teach You That...Well Then,They Done It Wrong
Some may disagree, but math on its own can be dry and boring. But if you hang in there and grab the basics you can use that to unlock all of physics. The application of trigonometry is how you can figure out where the sun really is setting. I didn't get this until I took college physics and realized those fundamentals finally came to light into something that I found super interesting.
this is my favorite duo collab 😭😭 y’all tg is so funny ong
When you think you’re being entertained but then, realize that you’re being educated by a real live science person. Thank you both.
☘️🌝🌲
A communicator*^.
'Poem'.. "Sun you're a liar!" and yet you inspire, Dreams of men that inquire, the knowledge in your fire. 😊
😊👌
no... this time it is ABOUT YOU... 🤣
our senses are "lying" rather failing to understand... not the sun... lol
sun been here doing this for longer then animals existed.. so who was it "lying" to before then?!
@@InanisNihil I think we all know that. OP just posted a nice little poem that wasnt meant to be take so seriously 😉.
Excellent! If you wrote that, get it registered. lol
Because I suspect it will make it's rounds on social media.
Sean Kavin I wonder why physics classes don’t make it as fun as these videos. We would all be In Mars by now
It's rare, and magical when you have 2 hosts with perfect chemistry. It makes or breaks a program. These guys have it. It's just as entertaining as it is educational. Doesn't get any better!
Because they are two pedos.
For the most part. Sometimes dude on the right makes some lame jokes, and sometimes I think neil is fake laughing.
@@anonymouscommenter7689 same.... the other dude is cringe to me, & often seems I am alone. Well, glad I am not d:-)
I would personally prefer less comic padding.
The material is interesting enough not to need spicing up,
so to me it's just distraction and dilution, especially the lamer moments.
Largely I think the mindset "learning needs to be fun", when taken (as it often is) to excess, becomes a way of papering over the cracks in the common first-world situation where teachers lack the ability to render the actual subject matter sufficiently interesting,
and kids have been pandered to by the "Must be Fun" brigade their entire life, to the point where they have little interest in the subject matter, even in those cases when it's *not* badly presented.
And here we see the same methodology in use with adults.
In very many ways, the American dream has become all about never having to grow up.
The real problem in the first world (it seems to me; I promise I'm about to climb down off my box!) is that the kids don't have any visceral connection with their need to know, whereas many kids in the third world will do whatever it takes to get themselves to school, given half a chance.
There are times when even mediocre teachers can do okay in some parts of the third world, as long as they don't actually get in the way of the kids arranging ways to learn stuff for themselves.
On a need to know basis. I love it. In my field of work I am the same way. You teach what needs to be known and get more in depth the more people try to actually learn and show a willingness to learn.
I love how he breaks everything down in such way that anyone can have a full conceptual understanding!❤❤❤
Neil: Are you winning sun?
Sun: "no dad refraction is lagging my light speed to reach human eyes"
This is the true sauce right here.
Best comment
This is the best thing I've seen all day
Perfect
Neil DeGrasse Tyson reciting the Moody Blues Nights in White Satin. BE STILL MY HEART. 😍😍😍
Will love to hear him recite The Rhyme of the Ancient Mariner
Eryn Morris: it's not Nights in White Satin. It's called "Late Lament/ Resolvement."
I don't know much about astrophysics, but I do know my music.
It's amazing someone bring up that song, I only heard it as a child a long time ago and just came across it recently. Love it!
I'm just really discovering these videos, and they are awesome! Thank you, Neil and Chuck, I'm enjoying your videos immensely.
I also discovered these quite late. Catchin up now ☺
Totally agreed and same, just found them and glad to have. Eye opening even if some is known it is great to add more knowledge.
@@romilpatel6957 Same!!!
I love that song. In the 70's radio, DJs didn't play that ending poem. Very sad for people who hadn't bought the vinyl record.
Neil: "fake sunset and sunrise"
FlatEarthers: *TRIGGERED*
I can already see (or hear) this sound byte in every FE video claiming Neil admitted there is no real sunset.
@@Morpheux1 Because quote mining and out of context statements is all they have.
@@alext7074 It's going to replace the NASA artist saying that the blue marble is Photoshopped because it has to be 🤣🤣🤣
@@aravindkrishnan3148 Some people just like to deny what they can't comprehend, unfortunately, our educational system is bankrupt.
Doesn't it already take 8 mins for the light from the Sun to reach earth so if a sunset and sun rise already happened, is that not 13 minutes late?
Schroedingers star. It’s both there and went nova millions of years ago
Actually it's more like its not there anymore , but we still see it . We see the past when we look at the stars .
It went to plaid
@@francoisrossouw9864 Actually everything you see is the past not just stars, but things closer to you are almost real-time.
@@MrT------5743 True
🤯🤯🤯
Was born in Chicago. Tall buildings. Never saw a sunset. Moved to sparse suburbs at age 4, and started running down the street to get the sun which was "right down there!" What a dope I was, having missed it by 5 minutes. 🙂
Neil is like the science teacher that I never had. I just love the way he gets excited while explaining things😍🤩
He like to lie. You are not seeing the sun go down behind a curve, it is disappearing because of the vanishing point (the point at which receding parallel lines viewed in perspective appear to converge) What you are watching in the video is two charlatans, trying to steal reality from you, so they can place their fiction in its place and use it to manipulate and control you.
He is like that because he is not teaching you real science . If he didn't simply make up the science to suit the central governments agenda , he might have some credibility . If he taught you the science , he would be just as boring as Mr. Wizard without a Timmy ! Those old enough to remember Mr. Wizard only tuned in to see how far Timmy could push Mr. Wizard , and how mad Mr. Wizard would get too , it was grate . See Neil can't even copy Timmy right , his cohost simply agrees with every nonsensical thing that Neil says .
“You are never actually looking at what you are looking it” that’s so true!!!! Star talk is so informative in an entertaining way love it ❤️
You are not seeing the sun go down behind a curve, it is disappearing because of the vanishing point (the point at which receding parallel lines viewed in perspective appear to converge) What you are watching in the video is two charlatans, trying to steal reality from you, so they can place their fiction in its place and use it to manipulate and control you.
And Chuck looks like he's been working out! Stay healthy stay hungry!
This is probably why there are so many schools of thought of astronomers using different references to determine dawn, dusk and other praying times, plus the provisions when to accomplish them.
Thank you for making this video.
Fantastic video as usual. Using the same principle of light from stars that reach us and could be gone for billions of years, it's worth mentioning that should our sun suddenly vanish, everything would look and feel absolutely normal around here for 8 minutes and 20 seconds, until we abruptly went into complete cold and darkness.
Interesting, as well, thank you for posting!!!
This is like my daily physics class.
If it's your physics class, it's awesome!!!
This is only half of what the public knows about physics... matter isn’t what’s real... the real secret is between all matter. The space force knows... electromagnetic gravitics will make rockets redundant.. tbh they were redundant before they were created.
That I actually understand and enjoy!
Aww that's sad , to think , how very little you are being left with , and you probably think he gave you the cosmos to .
The thought that the light from the stars is so old both excites and scares me when I look at the sky. It reminds me that I am both a temporary and eternal makeup of atoms in this universe.
It also means you are looking in the past. your eyes, even binoculars, or any kind of telescope are in fact... time machines :) that's pretty cool
And we also love Chuck's learning enthusiasm. That would be our youth and kids.
Love you guys, always interesting, entertaining, funny and educational. You're a perfect match for these explainers. I wish I knew you guys. Thanks
Possible one of the best moments in those videos, when Chuck fully grasps a concept and gets that excited! I love it
chuck: the universe is beautiful
Tyson: .... bootiful, bootiful
I absolutely love these videos.🥰 Keep up the great work you do and information you're providing to all of us
Thanks! Always useful entertainment in the form of information. And for the range of all age level s. When I get enough of a certain subject or focus , I look for another episode.
Next time I'm lighting a spliff watching sun set I'm gonna put on this video.
Thank you Dr Tyson!!!
Technically sunset occurred around 13 minutes previously from the observer on earth... it takes about 8 mins for light to travel from sun to earth plus the earth's atmosphere refraction of 5 mins.
LeftPinkie I was thinking the same thing
Yes, I understand the same. But my question If sunrise is 13 minutes early in some place that "ghost "must run faster to make up for those 26 minutes?
thank you I was wondering the same
With you I've learned more through this pandemia than my years of high school, thanks!!
The only thing you learned from these two is how to manipulate, people who do not know any better. You are not seeing the sun go down behind a curve, it is disappearing because of the vanishing point (the point at which receding parallel lines viewed in perspective appear to converge) What you are watching in the video is two charlatans, trying to steal reality from you, so they can place their fiction in its place and use it to manipulate and control you.
In ALL the years I've been on RUclips, I've subscribed to only 5 channels. StarTalk is one. I don't know how to give you guys a better compliment. You ROCK! As it should be
"When you wish upon a dead star. Makes no difference who you are." Chuck Nice to be back! One of the smartest comedian out there IMO. Neil is like the Book of Revelation.
13:30
Chuck totally nailed it!👍😀🔥
The hosts are completely symbiotic to the product. Perfectly matched for both, entertainment, and education. Also I love how Tyson clarifies - openly - a layman's perspective of Neil's explanations.
I could watch Star talk for hours. Thanks chuck and Neil
I’d love to see an episode where Neil gives his thoughts on using the sun (UV and IR) to gain energy (electricity and heat)
These gentlemen are fun to watch and listen. So informative and funny.
Totally agreed!!!
"Breathe deep, the gathering gloom.
Watchlights fade from every room.
Exit the people that beacon lament.
Another day's useless penny is spent.
Empassioned lovers wrestle as one.
Lonely man cries for love and has none.
New mother picks up and suckles her son.
Senior citizens with they were young.
Cold hearted orb that rules the night.
Removes the color from our sight.
Red is gray, and yellow white
but we decide which is right
and which is an illusion." ---The Moody Blues
Chuck, you are definitely the "yin" to Neil's "yang" I love star talk and you two have some next level synchronicity!!! science had been my guilty pleasure for the entirety of my adult life 🤣 thank you for all the content and knowledge 🙏🙏🙏 I truly appreciate your time,effort & energy👌#STARTALK4LIFE
I love Chuck's entusiasm! I feel the same way and it's nice to know I'm not the only one :)
You guys are a gift to humanity 💛
The way my astronomy professor in college phrased it, which made me go 'Whoa!' then and still does, was "Looking up at the night sky, you are looking into the past...because the light you see is actually how the star or galaxy appeared years, decades, centuries, milennia, sometimes even billions of years ago."
The universe and its wonders which we know in part, bears testimony, to the infinite knowledge, power and love of our creator. Always a blessing to listen to Tyson and the other guy, oh sorry Chuck.
Man I love the physics between you two lol
Would that be physics, or chemistry? :-)
Excellent service you and you're team delivery us all... on behalf of everyone sincerely thank you. MJJ
Chuck is such the perfect comedic foil for Neil's learned knowledge. And while I totally get Neil's explanations and need no filter, Chuck's irreverent absurdities are very entertaining. The two are the very definition of synergy. Definitely a most dynamic duo!
every time i watch him explaining something i feel like a child
A child that finally understands 👍
I love Chuck! He's the perfect co-host with NDT imo. Always love the episodes where he's present.
Oh my GOODNESS How I love you 2! Chuck, I move through life with VERY similar responses, lol! Y'all bring me JOY!!! OH, AND I GOT MY WEE ONES BOOK DELIVERED!! I can now do my readings with Dr. Tyson's Astrophysics for Young People in a Hurry. YAHOOO
The Moody Blues is my favorite. There are two ways to express the last line . Which is or which is? The illusion is the universe. Thanks for explaining refraction.
Chuck's reactions are what make this so awesome
Is no one going to talk about Chuck calling Neil "babe" at 16:01??😂🥰
So he did say that, thought I must've misheard.
😂😂😂
They probably a closeted couple
😂
I came to the comments section to check if someone else caught that first. I see we are many 🤔
You both are perfect combination of Wisdom and Fun
I'm just learning about refraction. It never occurred to me since I point my telescopes manually the stars may not actually be in the position I'm pointing at. Congratulations Neil you blew my mind again!
It's not just that they may not be in that position, they literally are not in that position. Proxima Centauri is 40,208,000,000,000 km away from our sun. That's the closest star but it still takes 4.35 years for that light to reach us and many stars are millions of light years away, some of the stars we see in the night sky might not even be there anymore or may have gone supernova (like the star Betelgeuse in the Orion constellation). It's long overdue for a massive explosion and it's too far from us to be harmful to us but when it does explode it's going to be spectacular, like those amazing space pictures you see of supernovas but right now we're in one of the most boring parts of our galactic neighborhood. When Betelgeuse explodes it will be the brightest object in the night sky; it could literally happen any day but then again it may have already happened but the light from that explosion will take 642.5 years to reach us.
@@liquidbraino I don't know if they mentioned it here (because of all the comic padding, I lost patience with trying to skip through and find out) but the effect you mention is an additional reason why the sun is not where it seems to be, it's where it was about eight minutes ago. Which at sunset makes quite a difference, but is also means that the time of (say) meridian passage - what navigators call "local apparent noon" is not the time of ACTUAL meridian passage. However instead of applying a correction which would always be the same amount, it's far simpler for the tabulated positions of the "sun" to actual denote the position of the IMAGE of the sun.
When I was in Undergraduate Pilot Training, my instructor in the T-37 aircraft liked to be the first one out the door in the morning, to create this visual illusion. We would go out to the acrobatics area, and he would tell me to do a loop. So I did, and the Sun came into view. Then we went over the top of the loop, and started down the backside, and the Sun would go down again. We could get about three iterations of this fun trick, and then move on to the rest of the lesson for the day. Thanks Derald.
In the morning when we watch the sunrise we are we are looking into the future. At Sunset we are looking into the past.
Not really. You are seeing the sun as it is (albeit as it was 8mins ago) in both cases. It's just the position of the image that is refracted.
JohnyG29 Yes but from our point of viewing. It has already set or has yet to rise over our horizon.
@@BondiAV er...no.
14:39 I love these guys so much
You had the same profile picture as me I was wondering when TF did I type this
Yeah. Nice profile pic btw
Did the Weird Al Yankovic routine on that poem for chemistry class: "Breath deep the gathering fumes ... watch life fade from every room ...." It goes on. In every chemistry class, lol!
If you ever read this Neil, you changed my mind profoundly.......as always............Thank you
Always very educational and entertaining. Thanks guys :)
Facts!!!
Everyone: wait the sun is in the center of the universe? (solar system)
Copernicus: Always has been
Well sun isnt the center of the solar system technically, bcz the star wobbles cauz of the planets (jupiter) around it and this is why the sun is also orbiting around something and that is.... Wait for it ..... Empty space.
i think neil is getting crazy.......thinking sun is an illusion
@@masternobody1896 Did you watch the video?
@@justsomeguy892 yep
@@masternobody1896 I don't believe you
Perfect timing - I watched this 3 days after the vernal equinox.
These videos are so intelligently choreographed to appear in my recommended videos list that all of your podcast helps me through each of my challenges
I was just talking about this to my friend.. like a minute ago..
BEFORE I FOUND THIS VIDEO..
I'm happy that I gave her a correct information.. hahahaha
Gotta love science 😆
Google is listening to you!!!🤫 Shh!!!
It's kinda scary when that happens, lol. But as someone mentioned maybe half in jest, Google is listening. But earlier today I was just thinking about a guy and certain videos he does and how I hadn't seen any in awhile, then BOOM! there's one of those videos. Is google listening to my thoughts?
There are 3 different sunrise and sunset times, astronomical, civil and physical (I think it’s physical). Thanks for another great video. BTW, Amateur Radio operators do EME communications by bouncing signals from Earth to the moon and back and can bounce the signals off the moon before the moon just peaks over the horizon due to refraction. Takes big antennas and lots of RF power as the moon scatters most of the signal.
66-year-old Iowan loving this channel. thanks
this evening I will watch a beautiful sunset with a new appreciation for it!
Neil sounding like a Jehova Witness
"I wanna talk about the son"
What the...
S-u-n
I'm glad you made it!
😂🤣😂🤣
🤣🤣🤣🤣🤣
So on the top of Mt Fuji. You see the reflection of the sun rise then the sun rise. It is the most beautiful sun rise over ever seen.
I did that Moody Blues poem as a computer art project in my high school in 1982. My hippie teacher liked it.
The comical rapport of these two is so great in the learning experience. Kudos.
and I was about to go to sleep...
Shoutout to brachistochrones, Snell’s Law and lamina flow.
I could watch Neil all day, everyday, with maybe a few cute puppy videos in between. Hey, Neil, put puppies in your videos and you'll create a channel that no one would ever turn off!!!
Love these explainer videos and the interaction between you two are amazing.
I would very much very much like to hear about the Earth ‘not ellipse’ orbit Neil, but I cant just drop by you Office since i am i Denmark 😄
I love the humour. I think my father actually explained all of this when I was about 6 or 7 years old and also why it appears to be 12 hours the nearer to the equator you are and why sunsets are way longer the further north or south you are.
I love when Chuck's mind is blown. He's pretty intelligent himself if he can keep up with what Neil is putting down.
This episode is one of my favorites! I really enjoy your videos!
Ohhhhh so fresh and energetic you guyz are !!! This is pure awesomeness melting in my ears !!! So refreshing and creating strong images to absorb those beautiful informations !!! Keep it coming ! Cheerzzz !!!
Yann
Wait. Earth’s orbit is not an ellipse? I need to know the rest!
Same
en.wikipedia.org/wiki/Milankovitch_cycles#Earth's_movements
I would have thought it would have a daily wobble due to the mass of the moon orbiting it too.
It is a spiral chasing the sun as it moves through space as well
So if some of the light you see in space is a ghost of a star that doesn’t exist anymore, then can it be possible that when humans die the same thing happens we become ghosts and still can be seen by some people but aren’t really there. How crazy
TV shows broadcast 50 years ago are still able to be seen, by 'people' 50 light years away.
"Looking at long past history" usually consumes my thoughts whenever I gaze at the stars. I've also contemplated that if we could exceed the speed of light, we would progressively see and hear further into the past the longer we travelled. Perhaps time travel isn't so far away after all! :)
A great team. Chuck Nice is a brilliant straight man…Now I have to find the earth’s orbit explainer. I gotta know!
This morning me and my friends cycled through the country fields for sunrise, we was questioning why the sunrise appears the way it does, it’s so much easier when an astrophysicist explains :D
"The sun is not going down. The horizon is coming up!" Fire Sign Theater
NDT is awesome it's always so entertaining listening to so many eloquent words just completely lying with the absolute confidence he's truly great at this. I mean he's one of the greatest.
Wow! I always wondered why the charts don’t show the 12/12 split on the equinoxes. Thank you!!!!!
We've found a way to beat the Fire Nation. Get Katara.
I like this comment but not katara
@@awilliams8778 Why?
@@aaubrey77 katara whines too much. I'm team Toph.
A Williams I like Toph too! ✌️
A Williams yeah Toph is a badass
Chuck lost me at "It's not all about you". I about lost my beverage on that one. Too funny.
From memory...hope it's correct...
one of my favorites...
"Cold-hearted orb that rule the night,
Removes the colors from our sight,
Red is gray, and yellow white...
But WE decide which is right...
And which is an illusion."
It takes approximately 9 minutes for light from the sun. When you see the sun you are seeing it where it was approximately 9 minutes ago.
When you look at a star 1000 light years away, you are seeing that star where it was 1000 years ago.
It is the inverse of shooting at a moving object. You do not aim at where the object is, you aim at where the object will be when the projectile reaches that same spot.