Kind: captions
Language: en
Recently, I was in New Zealand asking
the real tough questions like where did
the earth come from? Like what was it
before it was the earth? Like how did it
get here?
I don't want to do this anymore.
[laughter]
Those who were game to answer my
question realized that an explosion was
important to Earth's formation.
I suppose it was created from space. I
don't know. I don't know. Things that
explode in space.
I suppose just heaps of gas built up.
Bang. God planet.
Same with the sun and everything else.
So, you're saying it came out of some
sort?
I'd say I'd say it would have been gas.
Yeah. Would have been explosion.
And then after that, there was just a
planet there or that's that's a really
good question actually. I suppose it
would be a whole bunch of gases and then
bang, a planet started evolving. All the
gases were right.
Was there a particular explosion you had
in mind? Perhaps one you learned about
from a popular American sitcom?
From the Big Bang, maybe. Yeah,
the Big Bang. the big bang theory or
something like that.
It was a bunch of dust that was formed
during the Big Bang.
I've been to a couple of um museums here
in New Zealand and then it it all starts
with the Big Bang, it says. And then you
see a lot of um volcanic action.
The Big Bang theory. That's one of the
theories of how Earth was created.
Yeah.
So, the Big Bang created the Earth.
Yes.
It was like boom and Earth was there.
Now, the trouble with explosions, which
I was trying to hint at, is that they
tend to blow stuff apart. They're more
destructive than constructive. But what
we're looking for is a mechanism to form
the Earth, to bring things together. So,
how could the Earth form out of an
explosion?
Masses that were then clustered together
and compacted together and consolidated.
It was debris that gathered together
through gravity.
Okay. Where did that debris come from?
The uh the Big Bang, I suppose. original
that big explosion led to a whole bunch
of debris and then it collapsed down
because of gravity.
Yes.
Now we're on the right track. The
gravitational attraction between all
mass is what causes matter to clump
together into galaxies, stars, and
planets. There's only one little
problem. After the Big Bang, there were
only two elements, hydrogen, and helium
in the whole universe. So, how could we
form the earth including its oxygen,
carbon, nitrogen, silicon, aluminium? I
say it that way for my Australian
viewers. How could we form all these
other elements? Well, the truth is the
Big Bang didn't form the Earth, at least
not directly. The Big Bang formed
galaxies of stars. Let's focus in on one
of these stars in particular, one whose
contents will go on to form the Earth.
In this star, the lighter elements are
fusing together to form heavier
elements, carbon, nitrogen, oxygen, and
eventually all the elements up to iron.
Now, when this star runs out of nuclei
to fuse, it explodes. And out of that
debris could form either directly our
solar system or another star, which then
explodes and forms our solar system. So,
you could say the sun is a second or
third generation star. And you might
say, well, that would have taken a very
long time to occur. And it's true. The
Earth has been around for about 4 1/2
billion years, but the Big Bang happened
13.7 billion years ago. So, if my arms
span represents the time that the Earth
has been here, then the Big Bang would
be about here.
You're doing a bangup job, guys. So,
when people tell you that we're all made
of stardust, they're not trying to be
metaphorical or poetic necessarily.
They're being literal. The iron in your
blood was actually formed in the core of
a star at millions of degrees. We and
the world around us can only exist
because of the elements that were formed
in earlier stars.