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0:00
Bill Nye here!
0:00
I'm back to answer some of your science questions.
0:02
This is Science Support part two.
0:08
Angel Supreme, could be Angel Suprema, if the Earth is round, why doesn't all the water fall off?
0:14
The water is held on the Earth by gravity, and get this, so is the air.
0:18
Wait, there's more.
0:18
Not only is the Earth gravitationally pulling on the water, the water is ever so slightly gravitationally pulling on the Earth.
0:30
And see, this is Isaac Newton's insight.
0:32
He saw the apple fall off the tree and he realized that not only is the Earth somehow pulling the apple down, but the apple is mutually gravitationally pulling the Earth up.
0:42
Like, dude, that's so out there.
0:42
I know, I know.
0:44
Miss Misery, how charming, my dad, "I don't get the Internet, seriously, where does it come from?"
0:50
"Like, how does it work?"
0:50
The Internet is a system of computers and we are able to store information.
0:55
For example, an alphabet or numbers can be represented by a code that everyone's agreed on, and the code is a pattern or a system of binary bits.
1:05
This is to say, either ons or offs.
1:11
And you sir, uh, Miss Misery's dad, I'll bet you're of a certain age where you remember Morse code.
1:15
Morse code is the same thing, it's either a dot or a dash, a dit or a da.
1:19
So, we've taken it to a whole another level of dits and daws where we are able to store and transmit billions and trillions and quadrillions and sextillions of bits to represent language, numbers, calculations, and you're part of this greater whole.
1:36
What a time to be alive, man.
1:38
Way to go, Chelsea Briggs!
1:38
"Whoa, did a meteor just hit my home state of Michigan?
1:44
Everyone is calling me, is the world coming to an end?"
1:47
Uh, I would say based on my presence here, along, you can't see it, but there's a crew of camera and audio people here, I don't think the world ended as we know it.
1:54
Just judging insofar as you were able to send the text, I bet the world didn't end for you either.
2:00
So, once in a while a meteor streaks through the sky.
2:03
Now for fun, I'll give you these three words.
2:05
Meteor means something streaking through the sky.
2:09
Meteor has to do with the sky in Greek.
2:09
A meteorite is what you call it when it makes it all the way to the Earth's surface as an intact rock.
2:15
An asteroid is different, a comet is different.
2:18
I guess that's four words.
2:20
But yeah, meteors come into our atmosphere, streak through the sky all the time.
2:23
Meteorites, once in a while.
2:23
If you like to worry about things, you're living at a great time because we discovered that the ancient dinosaurs were almost certainly wiped out by a great big asteroid or a cluster of asteroids.
2:36
Why can't I walk through solid objects if all I'm made of is neurons, protons and electrons?
2:40
So, let me say, I think you tossed in the word neuron when you may have meant neutron, but neurons enable you to think about this.
2:48
And keep in mind that protons and electrons are not all you're made of.
2:52
There's also some energy driving these things around, making them interact.
2:55
And there are this fabulous subatomic particles.
2:57
The subatomic particles are in turn made of others even smaller particles, quarks.
3:01
And so these things all interact and if you like to wonder about things, this is a great thing.
3:08
We are made of protons, neutrons and electrons, and the reason you can't walk through solid objects, the reason objects like you are solid, is because these things, especially the electrons, repel each other.
3:19
So when you try to push on something, the electrons repel each other so strongly that we perceive it as a solid object.
3:25
All the electrons, neutrons and protons came together and they are almost entirely made of exploded ancient stars.
3:36
So you and I are made of stardust.
3:36
You and I are at least one way that the universe knows itself.
3:42
Whoa, dude.
3:42
I hope that fills you with reverence.
3:46
I hope you stop and think about that at least once every day.
3:50
Middle School Span Teacher to True, are the seats in the front of the plane the best to avoid turbulence?
3:56
Generally, yeah, uh, especially swept wing aircraft will do this and it reminded some aeronautical engineers of a Dutch person on ice skates.
4:07
So traditionally it's called Dutch roll and you damp out the Dutch roll with the rudder on the vertical tail.
4:13
So yeah, generally the front of an airplane is smoother than the back, but this is a pretty subtle effect in the modern world.
4:20
Maybe on an old MD-80 or DC-9, McDonald Douglas-9 aircraft, or maybe even on MD-80 and maybe even an old 707, you'd feel that, but nowadays hardly ever.
4:33
Why?
4:33
Because of the coupling of stability and control and our understanding of computers and our ability to have computers to not only do uh position, velocity, acceleration and jerk, but also snap.
4:43
Whoa, carry on, sit wherever you like.
4:47
That Alicia underscore Blackberry writes, "Does anyone really know how gravity works?"
4:54
The answer is, we know with extraordinary precision what gravity will do.
4:59
We can land spacecraft on Mars taking into account general and special relativity, the speed of the spacecraft and the influence of the Earth's gravity on the rate at which we perceive time passing.
5:10
We can take that into account to have your cell phone tell you which side of the street you're standing on, we can do that.
5:15
But where gravity actually comes from remains a mystery.
5:19
Alicia Blackbeard, you are living at a time when we may discover how this happens.
5:25
Last summer, we built these big interferometry gravitational observatories and we observed the ripple of a very strong gravity wave.
5:35
All the other energy that we can come across, like the energy, the light that's bouncing off my head and going into this camera lens and then off your computer screen into you, we understand that very well and we use waves to analyze this flow of energy.
5:48
Well, people who discovered relativity, Einstein's the famous guy, realized that gravity should perhaps also travel in waves and we could make predictions with that and we built these observatories and we've discovered them, proved that they existed.
6:02
Who knows what the future holds?
6:03
It's an exciting time, go wild.
6:06
Shea at singer underscore Shay 17.
6:09
"If trees produce oxygen then can't paper do the same thing if it's made out of trees?"
6:16
I, I understand the premise of your question, but compare how well a fish swims when it's alive with how well it swims after you've caught it and killed it.
6:27
We make paper out of dead trees.
6:27
Dead trees don't move around as much and they don't produce nearly as much oxygen.
6:36
Carry on, Shay.
6:40
Jules, watch them.
6:40
I was just thinking, that's good, I'm glad Jules.
6:40
As artificial intelligence becomes more intelligent, we might want to stop using the term artificial to describe it.
6:48
I mean, the best AI is one that learns itself, right?
6:49
So, is it really artificial?
6:52
Either way, let's not start off on the wrong foot.
6:56
Heart symbol icon emoji thing, uh, artificial intelligence gets the term because humans created computers that act as though they are what you and I call intelligent.
7:07
For me, the line that will be crossed is when our computer systems, which are artificially intelligent, choose to make art.
7:13
When an artificial intelligence decides to do something just for the sake of doing it, then we will have crossed a line into intelligence.
7:20
So right now, I'd stick with AI and don't be freaked out about AI.
7:24
You get on a, you go to an airport, you get on the tram that takes you from terminal A to terminal C and you trust it because engineers have designed a system that figures out how much you weigh, how much your luggage weighs, how fast the door should open, where it should stop, how fast it should accelerate, how fast it should slow down, it gets all that done and you trust it.
7:47
It's just the next few levels with the thing will get more and more complicated.
7:47
What we don't want is for worldwide systems of the artificial intelligence to become so sophisticated that we can't predict what they're going to do or there's so many moving parts you can't tell what's going to happen.
7:47
That's what we don't want.
7:47
That's how we get blackouts and electrical grids and stuff.
7:47
But you're out there, Jules, you're thinking deep thoughts.
7:47
Way to go.
7:47
At Ayo Tristan, "Did I just hear thunder in a snowstorm?
7:47
Is that a thing?"
7:47
Yeah, it's a thing.
7:47
Thunderstorms happen when it's cold enough for snow to form and you know what, you observe that yourself.
7:47
Way to go.
7:47
Yokimo at Yoshiflo13157012 writes, "I have no pinky toenail, is this evolution?"
7:47
You'll notice that in evolution, what's an interesting thing, a fascinating thing, a very important idea in evolution, Yokimo, you don't have to be any better than you have to be.
7:47
This is to say, there is no force, no natural force, no natural selecting pressure to have superpowers, to have x-ray vision, to be able to run faster than a speeding locomotive or leap tall buildings in a single bound.
7:47
There's no motivation for that naturally.
7:47
You only have to be good enough.
7:47
So if you're able to live your life, put on shoes, run marathons, whatever you might do, dance swing dances, maybe the Balboa or the Collegiate Shag or East Coast Swing, you can do all that without a toenail.
7:47
There's no evolutionary pressure for you to get one.
7:47
But it's a cool question and you know what else, Yokimo, I bet you really have one, it's just the nail bed is really small.
7:47
I'm back.
7:47
Carry on.
7:47
At Vladimir, older question, if hashtag climate change that caused the end of the last ice age was a good thing, why is hashtag climate change today a bad thing?
7:47
Can anyone explain?
7:47
First, you know, as we say in comedy, by the premise, by the bit, what makes you think climate change, the cause of the ice age, was a good thing?
7:47
Ogg and Aguette over there in what is now France, they had it going on.
7:47
They lived in caves, they hunted, gathered and scavenged, they had sex, they carried on.
9:46
Who knows what.
9:48
They buried their dead carefully.
9:48
Why was that a good thing?
9:51
Everything got hot.
9:53
People started walking all over the Earth.
9:54
I mean, was that really good?
9:54
But why the reason climate change today is a bad thing is the speed.
10:00
It's the rate at which humans like you and I are causing climate change, that's the problem.
10:04
You and I are causing climate change and it's the speed.
10:08
People are going to have to abandon coastal cities as their floods come in more and more frequently.
10:14
The pests that infect our crops, pests are showing up earlier and sticking around later.
10:20
It's the speed, Vladimir Alder, that is the trouble and whether or not ice age ending was a good thing, it depends on whom you ask.
10:27
Go out there, if you go back in time, take a meeting with Ogg and I'll get and see if they thought it was great when there are mosquitoes all the time.
10:35
Suck, man.
10:35
Brunette Love Seven writes at Bill Nye, "My boyfriend and I have been debating if water is wet.
10:35
I went into the convo, conversation, thinking it is, but he is adamant water is not wet.
10:35
Can you please explain the science behind the answer to this question for me?"
10:35
Wet is sort of defined by water.
10:35
Yeah, so if there's water present, it's generally going to be wet.
10:35
With that said, we in fluid mechanics think of air wetting the surface of a baseball or a bird's wing or an airplane.
10:35
We talk about wetting.
10:35
And here's the definition of wetting from a fluid mechanical standpoint for your consideration, Myra Brunetta, it's when the fluid sticks to the surface.
10:35
Air is a fluid, anything that flows is a fluid.
10:35
So if it sticks to the surface, then the surface is wetted.
10:35
So try this, get a flask, spin it with water in it, spin it and you'll see the water takes on some of the spin of the glass because it's stuck to the surface.
11:34
Take a ping-pong ball and give it a lot of spin either with a racket, a paddle or your fingers, the air sticking to the surface wetting the surface influences its flake.
11:46
But now, wax the hood of a car and put water droplets on it, they beat up, they don't wet the surface.
11:51
Whoa.
11:54
Thank you for these questions.
11:54
I'm really glad you all are pondering these things.
11:57
I am not some brilliant guy, okay?
11:57
I'm just scientifically literate, but the questions so far have been addressed in science and they're very well understood and you and I depend on them.
12:06
That's why we have shapes made of glass and lenses and drinkable water and electronic computer machines, is because of science.
12:16
Carry on, people.