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Lift off of Messenger on Nasa's
mission to Mercury.
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00:00:09,175 --> 00:00:16,025
They'll say no-one can see us
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00:00:16,060 --> 00:00:23,440
That we're estranged
and all alone
4
00:00:23,475 --> 00:00:30,785
They believe
nothing can reach us
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00:00:30,820 --> 00:00:38,100
And pull us out of
the boundless gloom
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00:00:38,135 --> 00:00:41,457
They're wrong
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They're wrong
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00:00:44,780 --> 00:00:49,420
They're wrong.
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00:01:06,580 --> 00:01:08,740
Beyond the inner solar system...
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past the asteroid belt...
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00:01:13,580 --> 00:01:14,620
lies Jupiter.
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00:01:17,340 --> 00:01:21,500
The largest of the planets
is a giant swirling ball of gas...
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00:01:25,460 --> 00:01:29,420
its marbled appearance generated
by violent winds
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00:01:29,455 --> 00:01:31,620
that rage through its clouds.
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00:01:41,340 --> 00:01:45,340
Jupiter is a world as strange
as it is remote.
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00:01:51,060 --> 00:01:54,345
If you fly upwards, only about
100km or so,
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you reach the edge of our atmosphere
and the blackness of space.
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It's really not that far.
19
00:01:59,692 --> 00:02:01,545
But once you're in space,
20
00:02:01,580 --> 00:02:05,305
the distance scales are sort of
incomprehensible.
21
00:02:05,340 --> 00:02:09,340
I mean, Venus, the closest planet,
is over 40 million kilometres away.
22
00:02:09,375 --> 00:02:12,665
Jupiter around 650 million
kilometres.
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00:02:12,700 --> 00:02:16,745
It takes our fastest spacecraft
years to get there.
24
00:02:16,780 --> 00:02:21,420
So, the idea that those planets
could have any influence on us
25
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here on Earth seems fanciful.
26
00:02:23,580 --> 00:02:25,425
And, indeed, if you're talking about
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your chances of meeting a handsome
stranger
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00:02:28,260 --> 00:02:31,940
or your life plans requiring a
moderate reconfiguration
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00:02:31,975 --> 00:02:35,585
about a week on Wednesday,
then you would be right.
30
00:02:35,620 --> 00:02:40,500
However, if you ask more profound
questions, deeper questions like,
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"Why is the Earth the way that it
is?
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00:02:42,895 --> 00:02:45,017
"Why is there life on Earth?
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00:02:45,052 --> 00:02:47,105
"Why do we exist at all?"
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00:02:47,140 --> 00:02:50,660
then it turns out that the planets,
and Jupiter in particular,
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00:02:50,695 --> 00:02:53,380
have had a profound effect.
36
00:03:09,420 --> 00:03:13,460
Early in its life, the young
Jupiter went on the rampage.
37
00:03:21,420 --> 00:03:24,940
The giant planet embarked
on a voyage of destruction
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00:03:24,975 --> 00:03:26,700
across the solar system...
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00:03:27,900 --> 00:03:31,260
that transformed the destiny
of the planets,
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00:03:31,295 --> 00:03:33,580
and the course of life on Earth.
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00:03:44,540 --> 00:03:47,940
Jupiter is the godfather
of the planets.
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00:03:50,020 --> 00:03:54,500
Understand it and you understand
how the solar system came to be.
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00:04:16,380 --> 00:04:20,940
On Earth, we can see glimpses
of Jupiter's power...
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00:04:20,975 --> 00:04:22,260
in the scars it's left...
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00:04:23,700 --> 00:04:25,580
on the face of the planet.
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00:04:38,340 --> 00:04:41,780
This is the famous Barringer
Meteor Crater in Arizona.
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00:04:41,815 --> 00:04:44,185
It is about a kilometre across,
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170 metres from the rim to the
crater floor
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00:04:47,795 --> 00:04:51,265
and it was created about 50,000
years ago
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00:04:51,300 --> 00:04:56,620
when a meteorite, 50 metres across,
entered the Earth's atmosphere
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00:04:56,655 --> 00:05:00,025
travelling at about 13km per
second.
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00:05:00,060 --> 00:05:02,500
That means it would have taken
around, what, seven seconds
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00:05:02,535 --> 00:05:05,697
to go from the top of the atmosphere
to the ground
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00:05:05,732 --> 00:05:08,860
and it hit with such force that the
energy released
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00:05:08,895 --> 00:05:12,017
was equivalent to ten megatons of
TNT.
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00:05:12,052 --> 00:05:15,140
And that is a very large
nuclear bomb.
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00:05:19,980 --> 00:05:22,105
The meteorite that hit the Earth
here
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00:05:22,140 --> 00:05:24,780
is thought to have come from the
asteroid belt...
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00:05:26,860 --> 00:05:30,700
the ring of rocky debris
that orbits at the edge
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00:05:30,735 --> 00:05:32,580
of the inner solar system.
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00:05:35,940 --> 00:05:38,585
And it was deflected from its orbit
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most likely by the gravitational
influence of Jupiter.
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00:05:51,300 --> 00:05:55,100
Jupiter is a completely different
class of planet to the Earth.
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A gas giant.
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A swirling ball of hydrogen
and helium so large
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00:06:04,375 --> 00:06:07,180
you could fit 1,300 Earths inside.
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00:06:13,980 --> 00:06:17,460
Jupiter can exert such a powerful
influence on the asteroids
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00:06:17,495 --> 00:06:19,025
because it's so massive.
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00:06:19,060 --> 00:06:22,420
It's about two-and-a-half times
the mass of all the other planets,
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00:06:22,455 --> 00:06:26,297
moons and asteroids in the solar
system combined.
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00:06:26,332 --> 00:06:29,816
And, therefore, it has a strong
gravitational pull.
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00:06:29,851 --> 00:06:33,265
And this means that Jupiter
exerts an influence
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00:06:33,300 --> 00:06:36,580
across the entire solar system
that's second only to the sun.
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00:06:38,340 --> 00:06:42,340
And that influenced us far
more than create the odd crater.
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00:06:42,375 --> 00:06:45,020
It can change the history
of worlds.
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00:06:56,420 --> 00:07:00,665
To understand how Jupiter rose
to such dominance,
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you have to go back to a time before
the solar system even existed.
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00:07:16,260 --> 00:07:19,145
Nearly five billion years ago,
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a distant exploding star sent
a shock wave across the galaxy...
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causing the cloud of gas and dust
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00:07:35,580 --> 00:07:39,300
that would become our solar system
to collapse...
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as the sun began to form.
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00:07:52,380 --> 00:07:56,700
But further out, something
else was growing.
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00:08:03,020 --> 00:08:04,700
After 50 million years...
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00:08:07,180 --> 00:08:10,020
the sun's nuclear furnace ignited.
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The light of its first dawn...
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revealing Jupiter...
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the solar system's first world.
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A planet born so early, it swept
up most of the material
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00:08:38,455 --> 00:08:41,380
left over from the formation of the
sun.
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00:08:47,940 --> 00:08:51,340
Because of its dominance, Jupiter
had a profound effect
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00:08:51,375 --> 00:08:53,865
on the newly forming solar system
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00:08:53,900 --> 00:08:57,460
and paved the way for our living
world to form.
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00:09:01,260 --> 00:09:03,785
This is a model of our solar system.
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00:09:03,820 --> 00:09:08,420
So, here's the sun, and then we have
the four inner rocky planets,
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00:09:08,455 --> 00:09:12,277
Mercury, Venus, Earth and Mars.
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00:09:12,312 --> 00:09:16,065
Then comes the asteroid belt,
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00:09:16,100 --> 00:09:21,020
the ring of millions of smaller
pieces of rock
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00:09:21,055 --> 00:09:22,997
orbiting around the sun.
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00:09:23,032 --> 00:09:24,905
And then the gas giants.
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Jupiter, Saturn, Uranus and Neptune.
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00:09:29,580 --> 00:09:32,660
Now, this has a pleasing regular
structure about it.
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00:09:32,695 --> 00:09:35,060
All the rocky planets close to the
star
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and the gas giants further out.
105
00:09:37,180 --> 00:09:41,180
And we thought that this must be the
natural order of things,
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00:09:41,215 --> 00:09:44,425
the way that solar systems
have to form,
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00:09:44,460 --> 00:09:48,265
until we started to detect planets
around distant stars
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and then we found that this
arrangement is not typical at all.
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00:09:58,220 --> 00:10:03,180
Our sun is just one of around
300 billion stars in our galaxy...
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and almost every one of those
stars
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is home to its own system of
planets.
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00:10:16,980 --> 00:10:22,340
In most other systems, the region
where our planet orbits is empty.
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00:10:25,580 --> 00:10:29,920
Instead, closer to the star, we see
super-Earths,
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vast rocky planets
many times bigger than our own.
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But, crucially, these worlds are
thought
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to have thick toxic atmospheres,
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making them completely inhospitable
to life.
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00:10:52,300 --> 00:10:55,145
And that raises a very interesting
question.
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00:10:55,180 --> 00:10:58,620
Why, then, is our solar system
the way that it is?
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00:11:08,060 --> 00:11:09,505
To answer that question,
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00:11:09,540 --> 00:11:12,820
we've sent spacecraft to every one
of the planets...
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00:11:15,380 --> 00:11:17,920
and they've uncovered strange
anomalies
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00:11:17,955 --> 00:11:20,460
that reveal our solar system's past.
124
00:11:23,540 --> 00:11:27,420
Our missions to Venus found
that it once had far more water
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00:11:27,455 --> 00:11:30,820
than you'd expect for a planet
so close to the sun...
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just as Earth does today.
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00:11:39,540 --> 00:11:41,705
The spacecraft we've sent to Mars
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00:11:41,740 --> 00:11:45,900
touched down on a world that is
curiously just half the size
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00:11:45,935 --> 00:11:49,260
of her sister planets Earth and
Venus.
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00:11:55,780 --> 00:11:57,305
And in the asteroid belt,
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00:11:57,340 --> 00:12:00,380
we've uncovered a graveyard
of failed worlds...
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their growth mysteriously cut
short.
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00:12:14,820 --> 00:12:16,505
To cause all these anomalies,
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00:12:16,540 --> 00:12:20,660
it's thought that something
catastrophic must have happened
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00:12:20,695 --> 00:12:23,060
very early in the solar system's
history.
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00:12:26,140 --> 00:12:30,020
All the evidence suggests
that around 4.5 billion years ago,
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00:12:30,055 --> 00:12:32,025
Jupiter's orbit began to change,
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00:12:32,060 --> 00:12:34,865
triggering a period of unprecedented
violence
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00:12:34,900 --> 00:12:39,020
which completely transformed the
face of the young solar system.
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00:12:39,055 --> 00:12:41,580
And we know this because
the marauding planet
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left a trail of destruction in its
wake.
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00:12:52,500 --> 00:12:57,100
Early in its life, Jupiter began
to move inwards towards the sun...
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00:13:00,460 --> 00:13:04,220
and the effects of that journey
can be seen to this day.
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00:13:14,260 --> 00:13:17,980
In between the orbits of Mars
and Jupiter...
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00:13:18,015 --> 00:13:19,660
lies the asteroid belt...
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00:13:22,700 --> 00:13:24,825
a desolate wasteland of debris
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00:13:24,860 --> 00:13:28,220
left over from the beginning
of the solar system.
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00:13:37,420 --> 00:13:41,660
Rocky bodies too small to be planets
in their own right.
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00:13:57,980 --> 00:14:01,300
In science fiction films, the
asteroid belt is often depicted
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00:14:01,335 --> 00:14:04,540
as an un-navigable
mass of tumbling rubble.
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00:14:04,575 --> 00:14:05,905
But it's not like that at all.
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00:14:05,940 --> 00:14:09,225
So much so, in fact, that modern
spacecraft engineers
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00:14:09,260 --> 00:14:12,900
can fly a spacecraft through without
making any course corrections.
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00:14:12,935 --> 00:14:16,837
The reason for that is there's not
much mass in the asteroid belt.
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00:14:16,872 --> 00:14:20,740
A sum total of all of them is only
about 4% the mass of the moon
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00:14:20,775 --> 00:14:24,225
and they're spread out in a huge
sort of ring,
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out beyond the orbit of Mars.
So, it's a vast amount of space.
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00:14:28,340 --> 00:14:32,320
That means that the average distance
between any two large asteroids
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00:14:32,355 --> 00:14:36,300
is about eight times the distance
between the Earth and the moon.
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00:14:36,335 --> 00:14:39,060
So, I could stand on one of those
large asteroids
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00:14:39,095 --> 00:14:40,585
and look out into space
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and my nearest neighbour would just
be a dim star in the dark.
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But scattered amongst the rubble
are objects
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that are far more than mere rocks.
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00:14:55,700 --> 00:14:58,465
Five, four, three,
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two, main engine start, one,
zero and lift off
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of the Delta II Rocket.
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00:15:06,820 --> 00:15:09,145
In 2007, Nasa's Dawn mission
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00:15:09,180 --> 00:15:13,660
was sent to explore the two largest
objects in the asteroid belt.
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00:15:35,980 --> 00:15:39,900
After a year in orbit around
the giant asteroid Vesta...
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00:15:45,740 --> 00:15:48,345
in March 2015...
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00:15:48,380 --> 00:15:51,585
Dawn made its final approach
on a body so large
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it makes up almost a third of the
mass of the entire asteroid belt...
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00:15:58,660 --> 00:16:01,220
Ceres.
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00:16:23,060 --> 00:16:26,700
On arrival, the first images Dawn
sent back to Earth
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contained something entirely
unexpected...
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00:16:37,540 --> 00:16:42,180
mysterious bright patches in one
of Ceres' largest craters.
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00:16:51,780 --> 00:16:53,705
Spectral analysis of the images
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00:16:53,740 --> 00:16:56,465
showed that the patches were, in
fact,
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00:16:56,500 --> 00:17:00,380
the salty residue left
behind by liquid water...
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00:17:02,980 --> 00:17:06,020
suggesting there must be large
amounts of ice
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00:17:06,055 --> 00:17:07,940
just beneath the crust.
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00:17:17,420 --> 00:17:22,620
Dawn went on to discover over 300
bright spots all over the surface.
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00:17:27,700 --> 00:17:30,345
And this means that beneath
this thin crust,
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00:17:30,380 --> 00:17:35,140
Ceres has a thick ice rich mantle
surrounding its rocky core...
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00:17:39,780 --> 00:17:44,540
evidence that the dwarf planet
is made up of multiple layers.
187
00:17:57,740 --> 00:18:02,160
The interior of Ceres is like
nothing else in the asteroid belt.
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00:18:02,195 --> 00:18:06,580
The differentiation, that separation
into layers, observed by Dawn
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00:18:06,615 --> 00:18:10,657
is more characteristic of a planet
than an asteroid.
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00:18:10,692 --> 00:18:14,700
So, 4.5 billion years ago, Ceres
was well on its way
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00:18:14,735 --> 00:18:16,620
to becoming a fully-fledged world.
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00:18:29,540 --> 00:18:33,300
It's thought that's in its infancy
Ceres was very different.
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00:18:37,220 --> 00:18:42,300
The water that now lies frozen
within its interior was once liquid.
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00:18:46,700 --> 00:18:49,500
Protected beneath a thin
layer of ice...
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00:18:51,620 --> 00:18:55,460
Ceres was once covered
by a deep saltwater ocean.
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00:19:13,460 --> 00:19:15,960
Before Ceres had reached
its full potential,
197
00:19:15,995 --> 00:19:18,407
a great disturbance sent shock
waves through
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00:19:18,442 --> 00:19:20,820
what would one day become the
asteroid belt
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00:19:20,855 --> 00:19:22,900
and cut its development short.
200
00:19:35,300 --> 00:19:37,945
As Jupiter circled the young sun,
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00:19:37,980 --> 00:19:41,100
it started to clear a path
through the gas and dust
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00:19:41,135 --> 00:19:43,100
that shrouded the early
solar system...
203
00:19:49,620 --> 00:19:53,700
but that process caused it to do
something alarming.
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00:19:56,100 --> 00:19:59,900
Gravitational interactions with the
gas made the giant planets
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00:19:59,935 --> 00:20:01,980
spiral inwards towards the sun...
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00:20:05,340 --> 00:20:07,620
ploughing straight through the
region of space
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00:20:07,655 --> 00:20:09,780
that would become the asteroid
belt...
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00:20:12,300 --> 00:20:14,700
scattering the material
from which Ceres
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00:20:14,735 --> 00:20:16,300
would otherwise have grown.
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00:20:23,100 --> 00:20:25,825
Computer simulations of the early
solar system
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00:20:25,860 --> 00:20:29,340
suggest that the asteroid belt once
contained enough material
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00:20:29,375 --> 00:20:32,337
to build a planet the size of the
Earth.
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00:20:32,372 --> 00:20:35,300
And perhaps that was Ceres's
destiny.
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00:20:35,335 --> 00:20:38,185
But when Jupiter passed through,
215
00:20:38,220 --> 00:20:42,260
it scattered 99.9% of the material
away,
216
00:20:42,295 --> 00:20:44,340
and Ceres's fate was sealed.
217
00:20:50,940 --> 00:20:54,860
Within 100 million years, Ceres's
ocean froze
218
00:20:54,895 --> 00:20:57,060
and was buried beneath its crust.
219
00:21:01,300 --> 00:21:04,220
The young planet's development
cut short
220
00:21:04,255 --> 00:21:06,740
before it could fulfil its promise.
221
00:21:19,580 --> 00:21:23,340
But Jupiter's reign of terror was
far from over.
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00:21:30,180 --> 00:21:32,185
It would continue its journey
inwards
223
00:21:32,220 --> 00:21:34,820
towards the place our planet
was beginning to form...
224
00:21:37,940 --> 00:21:40,980
threatening the very existence of
Earth.
225
00:21:46,180 --> 00:21:50,420
Jupiter had such an overwhelming
effect on the young solar system
226
00:21:50,455 --> 00:21:52,940
because of its powerful
gravitational field...
227
00:22:12,420 --> 00:22:15,900
the effects of which we can
still witness today.
228
00:23:10,460 --> 00:23:13,340
Jupiter exerts its influence
across the solar system
229
00:23:13,375 --> 00:23:15,260
through its gravitational field...
230
00:23:23,980 --> 00:23:27,140
which is by far the most powerful
of all the planets,
231
00:23:27,175 --> 00:23:30,300
because Jupiter is the most massive
of all the planets.
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00:23:30,335 --> 00:23:33,657
It's about 320 times the mass
of the Earth.
233
00:23:33,692 --> 00:23:36,945
That's why it was so destructive
in the past.
234
00:23:36,980 --> 00:23:40,625
And we see the power of
that gravitational field today
235
00:23:40,660 --> 00:23:45,780
in its influence on the closest
of Jupiter's largest moons, Io.
236
00:23:59,420 --> 00:24:02,700
Io is the most volcanic
world in the solar system.
237
00:24:07,820 --> 00:24:11,700
Its surface covered with hundreds
of active volcanoes...
238
00:24:16,900 --> 00:24:18,780
and lakes of molten lava.
239
00:24:25,380 --> 00:24:28,580
The largest, known as Loki Patera,
240
00:24:28,615 --> 00:24:31,780
is more than 200km in diameter.
241
00:24:40,980 --> 00:24:44,740
A million times the area
of any lava lake on Earth.
242
00:24:46,460 --> 00:24:49,900
Its surface tormented by waves
of molten rock.
243
00:25:02,700 --> 00:25:04,740
Io is a vision of hell...
244
00:25:10,500 --> 00:25:13,780
created by the moon's proximity
to Jupiter.
245
00:25:32,860 --> 00:25:37,260
Volcanism here on Earth
is powered by the internal heat
246
00:25:37,295 --> 00:25:39,025
down below the surface.
247
00:25:39,060 --> 00:25:41,100
Now, much of that is residual heat
248
00:25:41,135 --> 00:25:43,105
left over from the Earth's
formation
249
00:25:43,140 --> 00:25:46,780
four-and-a-half billion years ago,
about half of it, and the other half
250
00:25:46,815 --> 00:25:51,540
is down to radioactive decay of
elements around the Earth's core.
251
00:25:51,575 --> 00:25:53,940
Now, on Io it's different.
252
00:25:54,940 --> 00:25:56,585
Io's a much smaller world
253
00:25:56,620 --> 00:25:59,905
and so it didn't retain
much residual heat.
254
00:25:59,940 --> 00:26:03,820
So, there, the volcanoes are powered
by a different process.
255
00:26:03,855 --> 00:26:05,860
It's known as tidal heating.
256
00:26:12,620 --> 00:26:15,345
The energy that drives Io's
volcanism
257
00:26:15,380 --> 00:26:18,740
doesn't come from heat
stored within the moon.
258
00:26:22,100 --> 00:26:23,820
It's generated by gravity...
259
00:26:26,780 --> 00:26:30,060
because Io orbits just 350,000km
260
00:26:30,095 --> 00:26:33,340
from the tops of Jupiter's clouds.
261
00:26:49,740 --> 00:26:53,820
Io orbits at about the same distance
from Jupiter
262
00:26:53,855 --> 00:26:55,585
as our moon orbits the Earth.
263
00:26:55,620 --> 00:26:58,260
But because Jupiter is so much more
massive,
264
00:26:58,295 --> 00:26:59,625
Io goes around much more quickly.
265
00:26:59,660 --> 00:27:03,100
In fact, it goes around once every
42 hours.
266
00:27:03,135 --> 00:27:05,820
Now, if Io were Jupiter's only
moon,
267
00:27:05,855 --> 00:27:07,980
that orbit would be circular,
268
00:27:08,015 --> 00:27:09,260
but it isn't.
269
00:27:13,060 --> 00:27:17,860
The next moon out - Europa - goes
round Jupiter precisely once
270
00:27:17,895 --> 00:27:19,860
for every two orbits of Io...
271
00:27:24,340 --> 00:27:26,860
which means that every second
orbit,
272
00:27:26,895 --> 00:27:29,380
Io and Europa fall into
alignment.
273
00:27:31,540 --> 00:27:34,780
It's what's known as an orbital
resonance.
274
00:27:36,580 --> 00:27:38,865
That gives it a gravitational kick
275
00:27:38,900 --> 00:27:42,025
and that moves Io's orbit
into an ellipse.
276
00:27:42,060 --> 00:27:44,660
Now, that means that the
gravitational force's on Io
277
00:27:44,695 --> 00:27:47,825
are constantly shifting and changing
278
00:27:47,860 --> 00:27:50,825
and that stretches and squashes the
moon,
279
00:27:50,860 --> 00:27:55,580
and heats it up - by friction.
Now, that is called tidal heating
280
00:27:55,615 --> 00:27:58,940
and that is the origin of
Io's volcanoes.
281
00:28:11,300 --> 00:28:14,580
This process raises the temperature
in Io's interior,
282
00:28:14,615 --> 00:28:17,137
which would otherwise be frozen
solid,
283
00:28:17,172 --> 00:28:19,660
to more than 1,000 degrees
Celsius...
284
00:28:22,940 --> 00:28:24,700
creating its lava lakes...
285
00:28:28,140 --> 00:28:30,820
and powering immense volcanic
plumes...
286
00:28:33,660 --> 00:28:37,460
that rise up to 300km
from the moon's surface...
287
00:28:39,180 --> 00:28:40,820
and out into space.
288
00:28:45,940 --> 00:28:49,860
Io provides the solar system
with a vivid reminder...
289
00:28:51,260 --> 00:28:53,220
of the giant planet's power.
290
00:29:07,980 --> 00:29:10,860
Jupiter's intense gravitational
field...
291
00:29:13,020 --> 00:29:16,385
is the source of Io's
volcanism today.
292
00:29:16,420 --> 00:29:19,380
But we don't feel that gravitational
pull here on Earth,
293
00:29:19,415 --> 00:29:21,825
because Jupiter is so far away,
294
00:29:21,860 --> 00:29:24,905
but four-and-a-half billion years
ago,
295
00:29:24,940 --> 00:29:28,920
Jupiter was migrating inwards
towards the inner solar system,
296
00:29:28,955 --> 00:29:32,900
approaching the region where
Mars and Earth were forming.
297
00:29:39,020 --> 00:29:43,180
After passing through what would
become the asteroid belt...
298
00:29:44,620 --> 00:29:46,900
Jupiter entered the inner
solar system...
299
00:29:52,180 --> 00:29:55,700
continuing its journey, spiralling
towards the sun.
300
00:30:03,820 --> 00:30:07,340
Back then, the area where Mars
and Earth orbit today
301
00:30:07,375 --> 00:30:10,420
was densely packed with gas and
rock.
302
00:30:18,580 --> 00:30:22,220
But as Jupiter approached,
it wrought havoc...
303
00:30:24,580 --> 00:30:28,060
scattering the rocky material
in all directions...
304
00:30:30,660 --> 00:30:33,260
some sent careering into the
sun...
305
00:30:42,100 --> 00:30:45,660
others thrown out
into interstellar space.
306
00:30:53,060 --> 00:30:57,700
And it's this that may explain our
solar system's unusual structure.
307
00:31:00,740 --> 00:31:02,305
Here's the solar system today.
308
00:31:02,340 --> 00:31:06,460
The sun, the four inner rocky
planets, the asteroids and Jupiter.
309
00:31:06,495 --> 00:31:10,957
And what we think may have happened
is Jupiter made it inwards
310
00:31:10,992 --> 00:31:15,420
through where the asteroids
are, as far in as the orbit of Mars.
311
00:31:15,455 --> 00:31:18,145
And that would have cleaned out
quite a lot of the material
312
00:31:18,180 --> 00:31:22,660
in the inner solar system, leaving
less for the formation of planets.
313
00:31:22,695 --> 00:31:26,580
And that's why we don't see
super-Earths in our solar system.
314
00:31:26,615 --> 00:31:28,585
Those big massive rocky worlds
315
00:31:28,620 --> 00:31:32,340
that we see in orbit around so many
other stars.
316
00:31:32,375 --> 00:31:36,025
This also might explain
why Mars is so small.
317
00:31:36,060 --> 00:31:39,780
See, if Jupiter was orbiting
in the region that Mars was forming,
318
00:31:39,815 --> 00:31:42,500
there would have been much less
material here.
319
00:31:42,535 --> 00:31:45,225
And that might explain why Mars
320
00:31:45,260 --> 00:31:48,900
is only a tenth of the mass
of Venus and Earth.
321
00:31:59,380 --> 00:32:01,625
Had Jupiter continued to move
inwards,
322
00:32:01,660 --> 00:32:04,660
it would have had a similar effect
on the Earth...
323
00:32:07,020 --> 00:32:10,460
meaning the world we inhabit
might never have formed.
324
00:32:17,140 --> 00:32:21,740
But just as it looked as if Jupiter
would sweep everything away,
325
00:32:21,775 --> 00:32:25,220
something stopped the giant
planet in its tracks...
326
00:32:32,380 --> 00:32:36,540
because in the shadows of the
outer solar system,
327
00:32:36,575 --> 00:32:38,500
another planet was forming.
328
00:32:43,180 --> 00:32:45,780
The solar system's second gas
giant...
329
00:32:47,540 --> 00:32:48,940
Saturn...
330
00:33:01,380 --> 00:33:04,100
and its birth changed everything.
331
00:33:08,940 --> 00:33:12,300
When a planet forms in a disk
of material around a star,
332
00:33:12,335 --> 00:33:15,105
as Jupiter did in our solar system,
333
00:33:15,140 --> 00:33:19,385
it tends to clear out a gap in the
disk.
334
00:33:19,420 --> 00:33:22,700
Now, the material tends to fall
inwards towards the star.
335
00:33:22,735 --> 00:33:24,465
It's called the accretion
336
00:33:24,500 --> 00:33:27,220
and that drags the whole thing
inwards.
337
00:33:27,255 --> 00:33:29,905
And that's what happened to Jupiter.
338
00:33:29,940 --> 00:33:34,860
But, then, a less massive planet,
Saturn, formed further out.
339
00:33:34,895 --> 00:33:37,185
It cleared out its own disk
340
00:33:37,220 --> 00:33:40,700
and it too fell inwards
towards the sun,
341
00:33:40,735 --> 00:33:43,505
but more quickly than Jupiter.
342
00:33:43,540 --> 00:33:47,100
That meant that Saturn got
into a resonance with Jupiter.
343
00:33:47,135 --> 00:33:50,060
It went round once in orbit around
the sun
344
00:33:50,095 --> 00:33:52,265
for every two orbits of Jupiter
345
00:33:52,300 --> 00:33:56,340
and that has the effect of cleaning
out the whole region
346
00:33:56,375 --> 00:33:58,217
between the two planets.
347
00:33:58,252 --> 00:34:00,025
And that has the effect,
348
00:34:00,060 --> 00:34:04,220
through a series of complicated
gravitational interactions,
349
00:34:04,255 --> 00:34:06,465
of slowing and stopping the in-fall
350
00:34:06,500 --> 00:34:11,105
and eventually causing the two
planets to move back out again.
351
00:34:11,140 --> 00:34:16,140
And that is what happened to Jupiter
and Saturn in our solar system.
352
00:34:24,260 --> 00:34:26,580
Saturn caused Jupiter to retreat...
353
00:34:27,700 --> 00:34:29,785
leaving behind just enough
material
354
00:34:29,820 --> 00:34:32,300
from which the inner planets could
form.
355
00:34:35,780 --> 00:34:37,260
Mercury.
356
00:34:39,940 --> 00:34:41,220
Venus.
357
00:34:44,100 --> 00:34:45,460
Mars.
358
00:34:51,300 --> 00:34:53,540
And our home...
359
00:34:53,575 --> 00:34:54,980
the Earth.
360
00:35:01,340 --> 00:35:05,060
By preventing the formation of much
larger super-Earths,
361
00:35:05,095 --> 00:35:08,020
Jupiter allowed our planet to grow.
362
00:35:22,660 --> 00:35:27,660
And even as Jupiter's reign of
terror was drawing to a close,
363
00:35:27,695 --> 00:35:31,580
it provided one last parting
gift to our world.
364
00:35:45,940 --> 00:35:49,460
The young Earth formed in an arid
region of the inner solar system.
365
00:35:49,495 --> 00:35:52,825
There was very little water
that close to the sun,
366
00:35:52,860 --> 00:35:56,580
but as the Earth was forming,
Jupiter was already tacking back
367
00:35:56,615 --> 00:35:58,945
outwards again into the outer solar
system
368
00:35:58,980 --> 00:36:02,985
through the region that we now call
the asteroid belt,
369
00:36:03,020 --> 00:36:07,740
a region populated by many icy,
water rich comets and asteroids.
370
00:36:07,775 --> 00:36:10,425
And they were scattered back inwards
again,
371
00:36:10,460 --> 00:36:13,160
bringing water back into the inner
solar system.
372
00:36:13,195 --> 00:36:15,825
So, I think it is quite a wonderful
thought,
373
00:36:15,860 --> 00:36:20,320
that Earth is a water world today
because of the motion inwards
374
00:36:20,355 --> 00:36:24,780
and then back outwards again
of the massive planet Jupiter.
375
00:36:31,020 --> 00:36:35,440
This idea does seem quite
contrived, almost fantastical,
376
00:36:35,475 --> 00:36:39,860
but the more we learn about
the formation of solar systems,
377
00:36:39,895 --> 00:36:43,585
and the more we try to model
a system like ours,
378
00:36:43,620 --> 00:36:47,460
with four terrestrial, water-rich
planets close to the star
379
00:36:47,495 --> 00:36:50,225
and then the gas giants further out,
380
00:36:50,260 --> 00:36:54,700
the more we learn that perhaps all
these things had to happen,
381
00:36:54,735 --> 00:37:00,037
these unlikely movements and
interactions between the planets,
382
00:37:00,072 --> 00:37:05,340
in order to produce a system like
ours and a planet like ours.
383
00:37:05,375 --> 00:37:09,460
So, places like this may
be extremely rare.
384
00:37:24,660 --> 00:37:28,020
Today, Jupiter has settled
into a regular orbit
385
00:37:28,055 --> 00:37:31,380
back beyond the far edge
of the asteroid belt...
386
00:37:34,300 --> 00:37:38,380
its days of marauding through
the solar system at an end.
387
00:38:21,620 --> 00:38:24,300
Jupiter has been established
in a stable orbit
388
00:38:24,335 --> 00:38:26,385
for almost four billion years.
389
00:38:26,420 --> 00:38:29,540
If I was to sit here on Earth 3.8
billion years ago
390
00:38:29,575 --> 00:38:32,625
when life began and look
up into the night sky,
391
00:38:32,660 --> 00:38:36,265
I would have seen it shining
there as a point of light
392
00:38:36,300 --> 00:38:40,385
the same as it looks today,
distant and seemingly detached.
393
00:38:40,420 --> 00:38:44,420
And it's remained that way for the
vast expanse of time it's taken
394
00:38:44,455 --> 00:38:46,665
for evolution by natural selection
395
00:38:46,700 --> 00:38:52,140
to transform those first populations
of organisms into all this,
396
00:38:52,175 --> 00:38:55,700
to transform the Earth into an oasis
of life
397
00:38:55,735 --> 00:38:57,820
in the desert of the solar system.
398
00:39:08,260 --> 00:39:12,540
But Jupiter's influence over the
Earth remains to this day...
399
00:39:16,860 --> 00:39:20,740
and that's because, despite its
great distance from us...
400
00:39:22,100 --> 00:39:25,780
it retains a vice-like grip
over the asteroid belt.
401
00:39:40,740 --> 00:39:42,745
It's easy, I think quite natural,
402
00:39:42,780 --> 00:39:45,300
to think of the asteroid belt
as a single structure.
403
00:39:45,335 --> 00:39:47,860
A sort of ring of rock surrounding
the sun.
404
00:39:47,895 --> 00:39:50,545
But that's not
what it's like at all.
405
00:39:50,580 --> 00:39:54,540
In reality, each one of those
millions and millions of pieces
406
00:39:54,575 --> 00:39:58,620
of rock is following its own
individual orbits.
407
00:39:58,655 --> 00:40:00,985
And this remarkable animation
408
00:40:01,020 --> 00:40:04,700
is made up of ten years
of astronomical observations.
409
00:40:04,735 --> 00:40:08,745
And every point you see
on this animation...
410
00:40:08,780 --> 00:40:12,305
is a single asteroid,
apart from all the planets.
411
00:40:12,340 --> 00:40:16,580
And so you see Earth and Mars
and Venus whizzing around the sun.
412
00:40:16,615 --> 00:40:19,857
But the interesting one
is Jupiter...
413
00:40:19,892 --> 00:40:23,100
orbiting just outside the asteroid
belt.
414
00:40:24,300 --> 00:40:27,420
What you can see is that the
asteroid belt
415
00:40:27,455 --> 00:40:29,385
dances to Jupiter's tune.
416
00:40:29,420 --> 00:40:32,505
It's the conductor of the asteroid
belt, if you like.
417
00:40:32,540 --> 00:40:36,780
There are complex patterns
here, but there's also structure.
418
00:40:38,740 --> 00:40:42,340
And the reason for that is
the delicate interplay
419
00:40:42,375 --> 00:40:44,977
between the gravitational pull
of the sun
420
00:40:45,012 --> 00:40:47,580
and the gravitational force from
Jupiter.
421
00:40:49,460 --> 00:40:50,745
Now, what can happen is that
422
00:40:50,780 --> 00:40:53,580
perhaps because of an interaction
between two asteroids,
423
00:40:53,615 --> 00:40:55,705
perhaps they collide with each
other,
424
00:40:55,740 --> 00:40:59,380
or perhaps on their orbit
they line-up perfectly with Jupiter
425
00:40:59,415 --> 00:41:01,545
and get an extra gravitational kick,
426
00:41:01,580 --> 00:41:04,460
those asteroids can be disturbed
from this structure
427
00:41:04,495 --> 00:41:07,385
and be sent
inwards to the inner solar system.
428
00:41:07,420 --> 00:41:12,580
And by that mechanism, Jupiter
has a profound influence
429
00:41:12,615 --> 00:41:14,980
on the planets closer to the sun.
430
00:41:24,980 --> 00:41:27,745
Around 100 million years ago,
431
00:41:27,780 --> 00:41:32,180
an asteroid 10km across was ejected
from the asteroid belt.
432
00:41:36,660 --> 00:41:39,665
Dislodged by Jupiter's gravity,
433
00:41:39,700 --> 00:41:43,180
it was set on a collision
course with the Earth.
434
00:42:02,460 --> 00:42:06,065
When it struck, it generated
a fireball so hot,
435
00:42:06,100 --> 00:42:11,300
anything within a 1,000km
radius would have died instantly.
436
00:42:20,020 --> 00:42:23,700
The impact threw 300 billion
tonnes of sulphur
437
00:42:23,735 --> 00:42:25,020
into the atmosphere.
438
00:42:34,100 --> 00:42:37,385
And during the nuclear winter
that followed,
439
00:42:37,420 --> 00:42:42,460
75% of all species were wiped
from the face of the Earth.
440
00:42:50,300 --> 00:42:52,305
In one fell swoop,
441
00:42:52,340 --> 00:42:55,860
Jupiter changed the course
of our planet's history.
442
00:43:08,260 --> 00:43:10,745
There are a few places on Earth
today
443
00:43:10,780 --> 00:43:13,745
where you can catch a glimpse
of lost worlds,
444
00:43:13,780 --> 00:43:17,420
you can see Earth as it was millions
of years in the past
445
00:43:17,455 --> 00:43:21,220
and perhaps glimpse the Earth as it
might have been.
446
00:43:21,255 --> 00:43:22,745
And this is one of them.
447
00:43:22,780 --> 00:43:25,100
Today, this is the Colorado Plain,
448
00:43:25,135 --> 00:43:26,745
over a kilometre in altitude,
449
00:43:26,780 --> 00:43:30,440
south of Denver close
to the Rocky Mountains,
450
00:43:30,475 --> 00:43:34,065
but 200 million years ago,
this was at sea level.
451
00:43:34,100 --> 00:43:38,700
It was an ancient lake and the
ghosts of those lost worlds,
452
00:43:38,735 --> 00:43:41,265
the imprints of the past, can be
seen over there,
453
00:43:41,300 --> 00:43:45,540
because there are literally
thousands of dinosaur footprints.
454
00:44:11,500 --> 00:44:14,340
And here they are, the dinosaur
footprints.
455
00:44:14,375 --> 00:44:17,425
I find this absolutely remarkable.
456
00:44:17,460 --> 00:44:20,625
This is the footprint
of a sauropod dinosaur.
457
00:44:20,660 --> 00:44:24,140
That's one of the big ones. The big
herbivores with the long necks.
458
00:44:24,175 --> 00:44:27,397
This animal would have weighed
about 30 tonnes.
459
00:44:27,432 --> 00:44:30,585
It was tall enough to peer
over a two-storey house.
460
00:44:30,620 --> 00:44:34,380
What happened here is, probably
a herd of them, a group of them
461
00:44:34,415 --> 00:44:37,797
came lumbering across this lake bed
and, then,
462
00:44:37,832 --> 00:44:41,180
perhaps that same afternoon,
predators came,
463
00:44:41,215 --> 00:44:43,625
maybe following the herd.
464
00:44:43,660 --> 00:44:45,825
And that's these footprints here.
465
00:44:45,860 --> 00:44:48,625
The allosaurus', these three-toed
footprints.
466
00:44:48,660 --> 00:44:51,980
Much smaller animal, maybe
about twice the height of me,
467
00:44:52,015 --> 00:44:55,185
about two tonnes, very nimble and
agile.
468
00:44:55,220 --> 00:44:59,980
So, you see a whole story
played out here, frozen in time.
469
00:45:14,140 --> 00:45:17,340
Today, just their traces remain...
470
00:45:22,780 --> 00:45:24,820
but were it not for Jupiter...
471
00:45:26,260 --> 00:45:27,900
they might still be here.
472
00:45:45,660 --> 00:45:47,585
There are so many chance events,
473
00:45:47,620 --> 00:45:50,065
not only throughout the history of
Earth,
474
00:45:50,100 --> 00:45:53,800
but also spanning the entire history
of the universe
475
00:45:53,835 --> 00:45:57,500
for 13.8 billion years, without
which we wouldn't exist.
476
00:45:57,535 --> 00:45:59,900
There's an unbroken chain of life
stretching back
477
00:45:59,935 --> 00:46:02,417
four billion years here on this
planet.
478
00:46:02,452 --> 00:46:04,900
You interrupt or interject
at any point
479
00:46:04,935 --> 00:46:07,625
and life on Earth is different.
480
00:46:07,660 --> 00:46:11,400
But having said that, there are
major events that affected life.
481
00:46:11,435 --> 00:46:15,140
And one of them is the asteroid
that wipes out the dinosaurs.
482
00:46:15,175 --> 00:46:18,300
And, in that sense, it is certainly
true to say
483
00:46:18,335 --> 00:46:21,260
that without Jupiter, we wouldn't be
here.
484
00:46:38,260 --> 00:46:41,060
The godfather of the planets
paved the way for us
485
00:46:41,095 --> 00:46:42,740
to inherit the Earth.
486
00:46:48,540 --> 00:46:50,500
And although it occasionally
flings rocks
487
00:46:50,535 --> 00:46:52,380
from the asteroid belt our way...
488
00:46:53,540 --> 00:46:55,980
it also protects us...
489
00:47:02,420 --> 00:47:05,180
because for objects heading
towards the Earth
490
00:47:05,215 --> 00:47:07,905
from the far reaches of the solar
system,
491
00:47:07,940 --> 00:47:11,500
Jupiter's gravitational
field acts as a shield.
492
00:47:16,940 --> 00:47:21,220
Around a century ago, a lump
of rock and ice
493
00:47:21,255 --> 00:47:25,500
4km across and weighing
17 billion tonnes...
494
00:47:27,100 --> 00:47:30,260
was hurtling towards the inner
solar system...
495
00:47:34,740 --> 00:47:37,820
until Jupiter intervened.
496
00:47:40,620 --> 00:47:45,665
Five, four, three, two, one...
497
00:47:45,700 --> 00:47:48,360
We have ignition and lift off of
Atlantis
498
00:47:48,395 --> 00:47:51,020
and the Galileo Spacecraft
bound for Jupiter.
499
00:47:52,300 --> 00:47:56,620
70 years later, we witnessed
just how effective a shield
500
00:47:56,655 --> 00:47:58,260
Jupiter can be.
501
00:48:07,180 --> 00:48:09,740
Onboard the space shuttle
Atlantis...
502
00:48:11,060 --> 00:48:12,540
the Galileo orbiter.
503
00:48:22,380 --> 00:48:24,745
Three years after Galileo launched,
504
00:48:24,780 --> 00:48:29,740
comet Shoemaker-Levy-9 had been
captured by Jupiter's gravity.
505
00:48:38,780 --> 00:48:41,660
Locked in the giant planet's
embrace...
506
00:48:43,540 --> 00:48:46,700
tidal forces now began to tear
it apart.
507
00:48:54,060 --> 00:48:56,020
Its journey cut short...
508
00:48:57,100 --> 00:48:59,620
the comet now faced annihilation.
509
00:49:11,140 --> 00:49:13,745
After crossing the inner
solar system,
510
00:49:13,780 --> 00:49:16,740
Galileo passed through the asteroid
belt...
511
00:49:20,140 --> 00:49:22,540
approaching the spots from where
it would witness
512
00:49:22,575 --> 00:49:24,420
the comet's final moments.
513
00:49:35,220 --> 00:49:40,260
On July 16th, Galileo saw the first
fragments of the comet
514
00:49:40,295 --> 00:49:43,020
enter Jupiter's southern hemisphere.
515
00:49:55,140 --> 00:49:57,545
Pieces of comet Shoemaker-Levy-9
516
00:49:57,580 --> 00:50:00,780
struck Jupiter over the course of
six days.
517
00:50:04,780 --> 00:50:08,540
It was the first time a comet strike
had ever been witnessed.
518
00:50:29,660 --> 00:50:32,860
The most destructive impact released
energy
519
00:50:32,895 --> 00:50:36,060
equivalent to six million megatons
of TNT...
520
00:50:37,820 --> 00:50:43,180
leaving behind a giant dark
cloud 12,000km across.
521
00:50:52,580 --> 00:50:57,000
By capturing objects
and incinerating them on impact...
522
00:50:57,035 --> 00:51:01,420
Jupiter sweeps up bodies
from the outer solar system...
523
00:51:01,455 --> 00:51:04,340
that might otherwise collide
with Earth.
524
00:51:17,220 --> 00:51:19,065
Jupiter,
525
00:51:19,100 --> 00:51:22,040
the oldest and largest of
the planets,
526
00:51:22,075 --> 00:51:24,980
is the godfather of our
solar system.
527
00:51:28,660 --> 00:51:29,700
In youth...
528
00:51:30,740 --> 00:51:32,420
it went on the rampage.
529
00:51:40,980 --> 00:51:43,940
For some young planets, it spelt
disaster.
530
00:51:49,340 --> 00:51:51,960
But for others, like our own
world,
531
00:51:51,995 --> 00:51:54,580
it cleared the way for their
formation.
532
00:52:03,220 --> 00:52:06,060
And in adulthood, it created
the conditions
533
00:52:06,095 --> 00:52:07,780
that allowed us to rise...
534
00:52:12,620 --> 00:52:15,820
so we owe Jupiter a great debt.
535
00:52:17,580 --> 00:52:20,745
But as the dinosaurs found
to their cost,
536
00:52:20,780 --> 00:52:24,380
it's a debt that could be recalled
at any time.
537
00:52:29,260 --> 00:52:30,465
To the naked eye,
538
00:52:30,500 --> 00:52:34,220
Jupiter is one of the brightest
points of light in the night sky,
539
00:52:34,255 --> 00:52:37,940
and through a small telescope, it is
a beautiful banded world.
540
00:52:37,975 --> 00:52:40,345
But it feels distant, eternal,
541
00:52:40,380 --> 00:52:44,185
disconnected from events
here on Earth.
542
00:52:44,220 --> 00:52:48,100
But the more we've understood about
the history of the solar system,
543
00:52:48,135 --> 00:52:51,897
the more we've come to understand
that that is not the case.
544
00:52:51,932 --> 00:52:55,660
Jupiter has played an important
and perhaps decisive role
545
00:52:55,695 --> 00:52:59,137
in the stories of all the planets,
including Earth.
546
00:52:59,172 --> 00:53:02,580
So, the solar system is just that.
It's a system.
547
00:53:02,615 --> 00:53:06,665
Complex, interconnected and
interdependent.
548
00:53:06,700 --> 00:53:10,745
So, next time you see Jupiter,
just hold your gaze.
549
00:53:10,780 --> 00:53:15,980
Maybe think for a minute, because it
is so much more than just a point
550
00:53:16,015 --> 00:53:18,025
of light, or a planet, even.
551
00:53:18,060 --> 00:53:21,460
It is the great sculptor
of the solar system,
552
00:53:21,495 --> 00:53:24,380
the destroyer and creator of worlds.
553
00:54:05,860 --> 00:54:07,940
I think people are drawn
in by Jupiter
554
00:54:07,975 --> 00:54:10,785
because it's very mysterious.
555
00:54:10,820 --> 00:54:14,300
It's covered by clouds that hide
what's underneath.
556
00:54:14,335 --> 00:54:15,620
It's very violent.
557
00:54:17,260 --> 00:54:19,380
And it's very intimidating.
558
00:54:21,500 --> 00:54:23,300
It's also very beautiful.
559
00:54:24,300 --> 00:54:26,860
It has all these things going on
560
00:54:26,895 --> 00:54:29,385
and it's hard not to be taken in.
561
00:54:29,420 --> 00:54:34,780
T-minus ten, nine, eight, seven,
six...
562
00:54:34,815 --> 00:54:37,105
Such is Jupiter's mystique,
563
00:54:37,140 --> 00:54:40,185
it's been a recurring
target for space exploration.
564
00:54:40,220 --> 00:54:47,020
And lift off of the Atlas V with
Juno on a trek to Jupiter.
565
00:54:47,055 --> 00:54:51,660
In 2011, Nasa launched its latest
mission - Juno.
566
00:55:00,860 --> 00:55:03,065
When we launched the Juno spacecraft
567
00:55:03,100 --> 00:55:06,025
away from the Earth out towards
Jupiter,
568
00:55:06,060 --> 00:55:11,220
we didn't have enough speed to get
away out of the gravity of the sun,
569
00:55:11,255 --> 00:55:14,180
so we actually had to come back
to Earth,
570
00:55:14,215 --> 00:55:16,580
get a gravity assist from Earth,
571
00:55:16,615 --> 00:55:18,500
and then go out to Jupiter.
572
00:55:22,860 --> 00:55:26,700
After travelling for five
years, Juno finally arrived.
573
00:55:31,180 --> 00:55:35,220
This is a mission that goes closer
to the planet in its orbit
574
00:55:35,255 --> 00:55:37,145
than any other mission ever has.
575
00:55:37,180 --> 00:55:41,820
Only a few thousand kilometres from
the cloud tops and very, very fast.
576
00:55:41,855 --> 00:55:44,105
We go from pole to pole in two
hours,
577
00:55:44,140 --> 00:55:47,360
slipping between the radiation belts
in the cloud tops,
578
00:55:47,395 --> 00:55:50,580
getting the data as fast as we can
and getting out.
579
00:55:52,700 --> 00:55:55,305
So, in every way, Juno is breaking
new ground
580
00:55:55,340 --> 00:55:59,740
and that's allowed us to see things
that we couldn't have ever imagined.
581
00:56:04,500 --> 00:56:08,540
Juno's mission is to explore
the planets inside and out.
582
00:56:10,940 --> 00:56:14,260
And amongst the many scientific
instruments it has on board
583
00:56:14,295 --> 00:56:17,180
is its camera, JunoCam.
584
00:56:19,300 --> 00:56:24,065
You see all these swirls, you see
all sorts of spots coming up.
585
00:56:24,100 --> 00:56:29,900
You see all these vortices, you see
dramatic storm systems interacting.
586
00:56:35,460 --> 00:56:38,380
It's mind-blowingly beautiful
pictures
587
00:56:38,415 --> 00:56:41,300
that this little camera
has been taking.
588
00:56:43,980 --> 00:56:47,460
JunoCam was able to see
the Great Red Spot from up close.
589
00:56:49,140 --> 00:56:51,385
We can see height to the clouds.
590
00:56:51,420 --> 00:56:54,065
We can see features that look
like storms.
591
00:56:54,100 --> 00:56:58,420
Maybe it's hailing or snowing
ammonia on Jupiter.
592
00:57:01,820 --> 00:57:07,180
And the most startling thing that we
saw from JunoCam's imagery
593
00:57:07,215 --> 00:57:10,220
was that the poles of Jupiter
are actually blue.
594
00:57:14,060 --> 00:57:16,540
They are nothing like the orange
and white planet
595
00:57:16,575 --> 00:57:19,380
that we grew up thinking about as
children.
596
00:57:24,540 --> 00:57:28,420
Juno has just begun to unlock
Jupiter's secrets.
597
00:57:31,260 --> 00:57:33,105
And so, at last,
598
00:57:33,140 --> 00:57:36,780
the godfather of the planets
has begun to talk.
599
00:57:51,980 --> 00:57:56,020
A planet that began life
as an unremarkable rocky world...
600
00:57:57,620 --> 00:58:01,860
but transformed into one
of the jewels of the solar system...
601
00:58:03,380 --> 00:58:08,460
where shimmering rings of ice
harbour a potential home for life.
602
00:58:11,140 --> 00:58:12,340
Saturn.
603
00:58:16,100 --> 00:58:18,540
Journey through our solar system
with this free poster
604
00:58:18,575 --> 00:58:20,705
produced by the Open University
605
00:58:20,740 --> 00:58:23,540
and discover more about its planets
and moons.
606
00:58:28,180 --> 00:58:32,540
Order your free
copy by calling...
607
00:58:32,575 --> 00:58:38,105
Or go to...
608
00:58:38,140 --> 00:58:41,300
and follow the links
to the Open University.
609
01:08:30,500 --> 01:08:33,780
Journey through our solar system
with the Open University
610
01:08:33,815 --> 01:08:37,100
and discover more about its planets
and moons.
611
01:08:39,220 --> 01:08:42,660
Explore this and more with our
academic experts.
612
01:08:44,980 --> 01:08:48,060
Go to...
613
01:08:49,900 --> 01:08:52,420
and follow the links
to the Open University.
51583
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