1. |
What Are Stars?
03:43
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When you look up into the sky at night, what do you see?
Astrophysical phenomena vast distances away
A panorama of lights that’s fascinated us for millennia
Not to mention the fairly ordinary star we see each day
Our galaxy is a system of hundreds of billions of stars
Many are binaries and stellar clusters bound by gravity
There are dwarfs and giants, quasars, pulsars, neutron stars and more
Join me as we journey to unlock the mystery!
What are stars?
Nuclear furnaces converting hydrogen to helium
What are stars?
Creating atoms radiation heat and light
What are stars?
Spheres of superheated plasma held by gravity
What are stars?
Generating photons that make them shine so bright
We see them every night
What are stars
In areas of space with denser matter, such as nebulae,
Gravity causes clumps of mostly hydrogen to form
The temperature will rise as the cluster’s mass increases
Until nuclear fusion starts; you could say a star is born!
Remaining matter in the stellar cloud can collect to form objects
Like the planets in our solar system orbiting the Sun
Stellar wind disperses particles through a stellar system and beyond
The stuff of distant stars can be found in everyone!
When a star exhausts the supply of hydrogen in its core
What happens next? The answer will depend upon its mass
The outer layers of the star expand and start to cool
The mass declines, and gravity will cause our star’s collapse
In 5 billion years, our Sun will expand as a red giant,
Then contract until it settles as a white dwarf, dim and small
A larger star will erupt in brilliant supernova
Larger still, it will collapse to a black hole
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2. |
Solar System Song
03:34
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The planet Mercury, the closest to the Sun
The smallest planet in our system, it is #1
It's got a rocky surface, almost no atmosphere
A day on Mercury would take two Mercurian years!
The planet Venus, the brightest in our sky
The closest to the Earth in distance and in mass and size
A heavy atmosphere that keeps the heat inside
The surface gets so hot that even lead is liquefied!
You know the planet Earth - it's where the humans dwell
A molten mantle with a water-covered rocky shell
The Earth is not too cold, and it is not too hot
We'd better keep it that way if we are to have a shot!
The planet Mars - it's got two tiny moons
The reddish colour comes from iron in the sandy dunes
It's half the size of Earth, it's got some polar ice
We sent some robots but so far there is no sign of life!
These are the planets of the solar system
And in this song we will describe and list them
Passing along the planetary wisdom
The planet Jupiter, with its enormous size
It's more than twice as massive as the others all combined
A giant ball of gas around a solid core
With nearly 80 moons we know of but there could be more
The planet Saturn, with all its pretty rings
They're made of particles of water ice and other things
Two of its largest moons have oceans underground
It's the conditions where we might expect that life is found!
The planet Uranus - it's got a funny name
It's blue like Neptune but the planets are not quite the same
It rotates on its side, its rings are vertical
It's mostly icy water, methane, and ammonia
The planet Neptune, too far away to see
Smaller than Uranus but greater mass and density
Near supersonic winds, anticyclonic storms
Out near the Kuiper Belt is where you'll find this icy orb!
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3. |
Gotta Be Gravity!
04:01
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If I were to drop two objects from my hands
One heavy and one light – which would be the first to land?
If you said the same time, then I think you understand
But what could it be? It’s gotta be gravity!
Gravity is the property that causes objects to attract
With the strength of their pull in proportion to their mass
The distance between them squared? It’s inversely proportional to that!
What could it be? It’s gotta be gravity!
If you were in a rocket, accelerating at a certain rate
You couldn’t tell if it was gravity in a stationary state!
It’s gotta be gravity
Objects are pulling me
I’m pulling them microscopically
What? It’s gotta be gravity!
It’s gotta be gravity
Forming the galaxies
Shaping their trajectories
What? It’s gotta be gravity!
The story goes, the apple fell on Newton’s head
Then Albert Einstein changed the paradigm again
Found that gravitation results from spacetime being bent!
They’re asking what could it be? It’s gotta be gravity
What if instead of being linear, space and tine are curved
Then very massive objects like the Sun or the Earth
Bend spacetime itself so straight lines seem to swerve
What could it be? It’s gotta be gravity!
Here’s an analogy to help to explain:
Think of a bowling ball sitting on a four-dimensional plane!
So if I were to drop two objects from my hands
They would move as the curvature of spacetime demands
A curious phenomenon we don’t fully understand
And what could it be? It’s gotta be gravity!
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4. |
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Say I want to come and visit you just as fast as I can
Well I know nothing's faster than the speed of light, so maybe that would be my plan
But wait! if I want to go at lightspeed, assuming I have mass
It would take an infinite amount of energy to get me that fast
You see, some unusual things happen at extremely high speeds
Time starts to get wonky and an object's length starts to decrease
Now if you're in a fast-moving spaceship, you wouldn't notice this change
In other words, the laws of physics are invariant within your inertial frame
But the speed of light is constant independent of you
No matter how fast you're travelling, no matter what your point of view
And if it travels in a vacuum you can call it c
Because the speed of light is constant - I'm talking relativity
The speed of light
If you were flying in a spaceship at a high velocity
And I was standing still right here on Earth, waiting for you to come to me
The speed of light would appear the same to us, but there'd be a difference in time
So what would seem like hours from your perspective could feel like days from mine
Say we're in two fast-moving spaceships and we're having a race
You might measure my speed as zero as long as I keep pace
But light is a little bit different because no matter what your speed
Any time that you try to measure it you'll always get the same read
299,792,458 meters per second
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5. |
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Have you ever wanted to go to Mars?
Stand on top of Olympus Mons staring at the Martian sky
Lie in your space suit underneath the stars
Two tiny moons hanging overhead and the Earth a distant light
But did you know your life would be very hard?
Mars isn’t suitable for human life and there are many reasons why
Low gravity
No air to breathe
No magnetosphere
No radiation shield
Temperature low
No water flows
No food can grow
So do you wanna go?
Do you want to go to Mars?
Take a trip so very far
You’ll be the first generation on another planet
Build a new civilization for humanity
Never see the Earth again
Miss your family, miss your friends but we’ll
Settle on this world, yeah we’ll make it ours
If you say goodbye to Earth and live your life on Mars
The Martian atmosphere is very thin
Low pressure and temperatures keep water locked up as ice
The air was stripped away by solar wind
But maybe millions of years ago it was more suitable for life
And when a storm of dust starts blowing in
You might find that life on Mars just isn’t very nice
I love the Earth…
Mars ain’t the kind of place we could substitute for Earth
And whether it can be terraformed is currently unknown
It could never match the biodiversity of our pale blue dot
However far we may go, this world will always be our home
But…
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6. |
Space Isn't Empty!
04:44
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We might think that denser regions of space are where the scientific action is
That the study of galaxies, stars and nebulae would be the most informative
And we might think that interstellar space would be a comparative snooze
But there’s a lot about so-called empty space that is fascinating too
Vera Rubin realized all the mass in the galaxy can’t account for its rotation
There must be many times more mass to have sufficient gravitation
Which means most of the matter in the cosmos is of a type we can’t perceive
Dark matter is the name we give to this cosmic mystery
We might think that interstellar space is as cold as anything can be
But space is slightly warmer than absolute zero by 2.7 degrees
Because of cosmic microwave background radiation left over from the big bang
With patterns that can show us how the early cosmos was arranged
We might also find super-high energy particles called cosmic rays
Released from stars and supernovae, perhaps beyond the Milky Way
And we might find massless bodies such as photons in interstellar space
With light, x-rays, and gamma rays, it can be quite a busy place!
We might find quantum fluctuations in what we think is empty space
Where a particle will appear along with its antiparticle mate
Existing only for a moment, they annihilate, and then are gone
The uncertainty principle predicts this strange phenomenon
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7. |
Time To Talk Time
03:03
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It’s time to talk time!
Now we can’t imagine existence outside time
So how do we define time? How do we describe time?
Can we talk about a time before time? A time perpendicular to time?
Is time infinite, or can its limits be defined? Quantified?
It’s time to talk time!
Can we describe time as loops or lines?
Einstein theorized time as part of curved spacetime
So we define the fourth dimension as time
The question is why we only go one direction in time
Is there a beginning or an end to time?
Maybe not if gravity can bend time
It’s time to talk time!
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8. |
The Fermi Paradox
04:35
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If there are hundreds of billions of stars in our galaxy alone
With potentially billions of planets in their habitable zones
Then even with million to one odds of intelligent life
Statistically speaking, we’re probably not alone
But I’ve never seen an alien – have you?
So assuming for the moment that our hypothesis is true
Then as the physicist Enrico Fermi once asked,
Where is everybody? So I pose the question to you:
On a planet formed 5.5 billion years ago
Where life had a billion-year head start to grow
If you can fly across the galaxy in a mere million years
The question is why haven’t we seen them before
Consider:
A civilization a million years older than ours
A superintelligent people who travel the stars
Then just as we send signals out into space
You’d think evidence of such beings could be seen from afar!
So I ask:
Maybe life will inevitably come to an end
Maybe they communicate in a way that we can’t comprehend
Maybe they exist in a form that we can’t perceive
Maybe they live in a place they don’t ever need to leave
Maybe we inhabit a lonely backwater of space
Maybe they don’t have any interest in this primitive place
Or maybe we just need a little bit more time
It’s a humbling thing to look up into the sky
At the tiny fraction of the universe that’s visible to our eye
Whether life is all around us, or so rare that we’re alone
It’s truly remarkable that we can even ask why
So be good to each other, cuz we’re a single human race
With the intelligence to understand the challenges we face
If we all work together, we can reach for the stars
And discover the mysteries that await us in space
And find out:
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Dr G Halifax Regional Municipality, Nova Scotia
Dr G is a theremin-playing space geek on a mission to spread the word about science! Merging hooky new wave beats with lyrics explaining science and the natural universe – think Talking Heads fronted by Bill Nye the Science Guy – Dr G creates a sound that is utterly unique, and as educational as it is infectious. ... more
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