Scale of earth and sun Scale of Earth and Sun
Scale of earth and sun
- My goal in this video and the next video is to start
- giving a sense of the scale of (really, just) the Earth
- and the solar system, and as we see as we start getting into
- (like) the galaxy and the universe
- it just becomes almost impossible to imagine
- but we'll at least give our best shot.
- So I think most of us watching this video know
- that this right here is Earth.
- This right here is Earth.
- And just to get a sense of scale here, I think, probably...
- probably, the largest distance that we can somehow relate to...
- is about a hundred miles [ 100 miles ~ 161 km].
- You can get into a car for about an hour, hour and a half
- and go about a hundred miles.
- And on the Earth, that would be about THIS far.
- It would be a speck that would look something like that.
- That is a hundred miles!
- And also to get us a bit of scale,
- let's think about a speed that at least we can kind of comprehend.
- And that would be maybe the speed of a...
- Let's think of the speed of a...
- Bullet. Speed of a bullet.
- Maybe we can't comprehend it.
- But I'll say that this is the fastest thing that we can maybe kind of comprehend.
- It goes about...
- (and there are different types of bullets
- depending on the type of gun and all of that)
- about 280 meters per second,
- which is about 1000 kilometers per hour.
- And this is also roughly the speed of a jet.
- Of a jet...
- So just to give a sense of scale here, the earth's circumference,
- if you were to go around the planet,
- the earth's circumference, just like that, is about 40 000km
- 40 000km...
- So if you were to travel at the speed of a bullet,
- speed of a bullet,
- or the speed of a jet liner, 1000km/h
- it would take you 40 hours to circumnavigate the Earth
- 40 hours to go around the Earth...
- And I think (these) none of these-this information is too surprising
- you might have taken a 12- or 15-hour flight
- that get you, not all the way around the Earth,
- but get you pretty far:
- San Francisco to Australia, or something like that.
- So right now these aren't at scales that are too crazy,
- although (you know), even for me, even the Earth itself is a pretty
- mindblowingly large object.
- Now, (with that out of the way), let's think about
- the Sun.
- Because the Sun starts to approach something far more huge.
- So this, obviously here, is "the Sun".
- And I think most people appreciate that the Sun is larger, that it's MUCH larger than the earth,
- and that it's pretty far away from the Earth,
- but I don't think most people, including myself,
- fully appreciate how large the Sun is, or how far it is away from the Earth.
- So just to give you a sense: (the Earth) the Sun has, the Sun is
- 109*circumference of the Earth!
- Times the circumference of the Earth!
- So if we do that same thought excersise there
- if we said: Ok, if i'm travelling at the speed of a bullet, or the speed of a jet liner,
- it would take me 40 hours to go around the Earth
- well, how long would it take to go around the Sun?
- So if you were to get on a jet plane, and try to go around the Sun,
- or if you were to somehow ride a bullet, and try to go around the Sun
- do a complete circumnavigation of the Sun
- it's going to take you
- 109, times, as long as it would have taken you to do the Earth.
- So it would be 100, times, (I could do 109, but just for approximate)
- it's roughly 100*the circumference of the Earth
- so 100*40=4000
- 4000 hours!
- And just to get a sense of what 4000 is
- actually, since I have the calculator out
- let's do the exact calculation:
- It's 109*the circumference of the Earth
- 109*40 hours
- that's what it would take you to do a circumference of the Earth.
- So it's 4360 hours to circumnavigate the Sun,
- going at the speed of a bullet, or a jet liner!
- And so, that is: (24 hours of the day)
- that is 181 days!
- It would take you roughly half a year
- it would take half a year to go around the Sun, at the speed of a jet liner.
- (let me write this down)
- Half a year!
- half a year...
- The Sun is HUGE!
- The Sun is huge!
- Now, that by itself may or may not be strange
- Actually, let me give you a sense of scale here
- I have this other diagram of a Sun.
- This other diagram of a sun...
- We'll talk more about the rest of the Solar Sytem in the next video.
- But over here, at this scale, the Sun
- the Sun, atleast on my screen, if I were to complete it
- it would be about 20 inches in diameter.
- The Earth is just this little thing over here!
- Smaller, smaller than a raindrop
- it's just this small little thing over here.
- If I were to draw it on this scale, where the Sun is even smaller,
- the Earth would be about that,
- the Earth would be right about that big.
- Now, what isn't obvious, because
- we've all done our science projects in 3rd and 4th grade,
- (or you) we always see these diagrams, of the solar system, that looks something like this:
- Is that the planets are WAY further away
- even though these are (this is) (these are), uhm
- depicted to scale, they are WAY further away from the Sun than this makes it look.
- So the Sun (sorry), the Earth; is 150 million kilometres from the Sun.
- So the Earth, Earth is:
- so this distance, (this is) if this is the Sun right here
- if this was the Sun right here, you wouldn't even
- at this scale, you wouldn't even be able to see the Earth!
- Wouldn't be able to see the Earth...
- It wouldn't even be a pixel.
- But it would be a 150, it would be 150 MILLION
- 150 000 000km from the Earth.
- And this distance right here is called an astronomical unit
- we'll be using that term in the next few videos
- just cause it's an easier way to think about distance.
- Sometimes abbreviated "AU": "Astronomical Unit".
- Astronomical Unit...
- And just to give a sense of how far this is
- light, which is something that we think is almost infinitily fast
- (that, you know) something that looks instantaneous
- THAT takes 8 minutes to travel from the Sun to the Earth!
- If the Sun were to disappear, it would take 8 minutes for that light,
- for us to know, that it disappeared on Earth.
- Or another way, just to put it in the sense of this jet air plane
- let's get the calculator back out
- So we have a hundred, we're talking about 150
- that's thousand, million!
- That's 150 million kilometres.
- So if we're going at 1000km/hour
- going at 1000km/hour, it would take us:
- 150 000 hours, at the speed of a bullet, or the speed of a jet plane
- to get to the Sun, and just to (get) put that in perspective:
- (that) if you wanted it in days: there's 24 hours/day
- so this would be 6250 days, or if you were to divide by 365:
- Roughly 17 years!
- If you were to shoot a bullet straight at the Sun, it would take 17 years to get there!
- If it could maintain it's velocity somehow
- So this would take a bullet or a jet plane 17 YEARS to get to the Sun.
- 17 years...
- Or another way to visualize it:
- This sun right over here looks (on my screen) it has about a 5" or 6" diameter.
- If i were to actually do the scale: This little dot right here,
- this little dot, which is the Earth, this speck
- this speck...
- If I actually wanted to draw this distance at scale,
- I would have to put this speck about 50 feet away from the sun
- 50-60 feet (15-18m) away from the Sun.
- If you were looking at the Solar System,
- and obviously there's other things in the Solar System,
- we'll talk more about them in the next video.
- You wouldn't even notice this speck! Just this little dust thing flying around this Sun.
- (And we) as we go further and further out of this Solar Sytem we're going to see
- even THIS distance starts to become ridiculously small
- Or another way to think about it:
- If the Sun was about this size,
- If the Sun was about this size...
- then this speck, then the Earth on this scale,
- would be about 200 feet (60m) away from it!
- So you could imagine, if you had a football field,
- if you had a football field...
- Let me draw a football field...
- These are the end zones:
- One end zone, another end zone,
- and if you were to stick, something maybe the size of a medicine ball,
- a little bit bigger than a basketball at one end zone,
- this little speck would be a- about 60 yards away or (about) roughly 60 metres away
- (so this little speck) you wouldn't even notice it, on the scale of a football field!
- Something this size.
- Anyway, I'm going to leave you there, hopefully that gives you just
- (eh) starts to blow your mind, when you think about just the scale of the Sun,
- the Earth, and how far the Earth is away from the Sun.
- And then we're going to see even those distances, even those scales
- are super small when you start thinking about the rest of the Solar System,
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At 5:31, how is the moon large enough to block the sun? Isn't the sun way larger?
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