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