Browse content similar to Voyager: To the Final Frontier. Check below for episodes and series from the same categories and more!
Line | From | To | |
---|---|---|---|
The instinct to explore is one of the qualities that defines us | 0:00:08 | 0:00:12 | |
as human beings. | 0:00:12 | 0:00:14 | |
It's propelled us across vast oceans | 0:00:14 | 0:00:17 | |
and to every corner of every continent. | 0:00:17 | 0:00:20 | |
But far, far away from these shores, two tiny spacecraft | 0:00:21 | 0:00:26 | |
are lifting this spirit of exploration to extraordinary levels. | 0:00:26 | 0:00:30 | |
For three and a half decades, | 0:00:32 | 0:00:33 | |
they've been investigating the outer reaches of our solar system. | 0:00:33 | 0:00:37 | |
They are the Voyagers. | 0:00:38 | 0:00:41 | |
Voyager was the right spacecraft at the right time, | 0:00:42 | 0:00:47 | |
when a huge amount of stuff was waiting to be discovered | 0:00:47 | 0:00:51 | |
and Voyager was capable of discovering it. | 0:00:51 | 0:00:53 | |
Voyager was the seminal mission of the past 50 years. | 0:00:53 | 0:00:58 | |
It represents the golden age of space exploration. | 0:00:58 | 0:01:00 | |
The Voyager journey has been driven | 0:01:00 | 0:01:04 | |
by remarkable human endeavour and achievement. | 0:01:04 | 0:01:08 | |
They've been a window into worlds almost beyond imagination. | 0:01:08 | 0:01:12 | |
And they've have helped unlock the secrets of our solar system. | 0:01:15 | 0:01:19 | |
For many of us, they're probably best known for carrying | 0:01:23 | 0:01:26 | |
a kind of message in a bottle. | 0:01:26 | 0:01:28 | |
A record of humanity here on Earth, | 0:01:28 | 0:01:30 | |
meant for any extraterrestrial civilisation that may find them. | 0:01:30 | 0:01:34 | |
Each spacecraft carries a golden disc. | 0:01:34 | 0:01:38 | |
It holds a snapshot of humanity, a dispatch to the stars. | 0:01:38 | 0:01:42 | |
'Hello from the children of planet Earth.' | 0:01:42 | 0:01:46 | |
And now the Voyager mission is about to cross the final frontier. | 0:01:47 | 0:01:51 | |
They are the first objects built by humans | 0:01:51 | 0:01:55 | |
ever to pass beyond the solar system and into the galaxy beyond. | 0:01:55 | 0:01:59 | |
This is the tale of the two most intrepid explorers | 0:02:01 | 0:02:03 | |
in our planet's history. | 0:02:03 | 0:02:05 | |
This is the Voyager story. | 0:02:07 | 0:02:09 | |
Right, here we go. 1977, | 0:02:26 | 0:02:28 | |
a good year for music. | 0:02:28 | 0:02:32 | |
The question is, what do you start with? | 0:02:32 | 0:02:35 | |
Do you go with a crowd pleaser or do you go with your favourite track? | 0:02:35 | 0:02:39 | |
MUSIC: Never Going Back Again by Fleetwood Mac | 0:02:40 | 0:02:42 | |
Brilliant. | 0:02:45 | 0:02:47 | |
# She broke down and let me in... # | 0:02:50 | 0:02:53 | |
It's 1977, and Fleetwood Mac have just released Rumours. | 0:02:53 | 0:02:59 | |
The world feels like a different place. | 0:02:59 | 0:03:01 | |
..of the United States... | 0:03:01 | 0:03:03 | |
Jimmy Carter is the ne, American president. | 0:03:03 | 0:03:08 | |
and Elvis has just died. | 0:03:08 | 0:03:10 | |
The cause of death is cardiac arrhythmia. | 0:03:10 | 0:03:13 | |
And technologically, it's a million miles from today. | 0:03:14 | 0:03:18 | |
A new company called Apple Computers has just been founded. | 0:03:20 | 0:03:25 | |
# I was strolling on the moon one day. # | 0:03:25 | 0:03:29 | |
And it's not long since the final Apollo mission landed on the moon. | 0:03:29 | 0:03:32 | |
'One of the most proud moments of my life.' | 0:03:32 | 0:03:34 | |
And this new technological confidence has fuelled | 0:03:34 | 0:03:38 | |
something else - a renewed interest in science fiction. | 0:03:38 | 0:03:40 | |
The public has gone crazy for films like Star Wars | 0:03:40 | 0:03:45 | |
and Close Encounters Of The Third Kind. | 0:03:45 | 0:03:47 | |
And this combination of breakthrough technology and exciting | 0:03:49 | 0:03:54 | |
science fiction has helped to inspire a surprising project. | 0:03:54 | 0:03:59 | |
Because in August 1977, NASA began one of the greatest adventures | 0:04:04 | 0:04:09 | |
in the history of spaceflight. | 0:04:09 | 0:04:11 | |
"Three, two, one, zero." | 0:04:11 | 0:04:15 | |
Here were two unmanned space probes, | 0:04:17 | 0:04:19 | |
attempting something straight out of an Arthur C Clarke story. | 0:04:19 | 0:04:24 | |
Their mission - to explore the outer planets of the solar system... | 0:04:32 | 0:04:37 | |
..Jupiter, Saturn, Uranus and Neptune. | 0:04:38 | 0:04:42 | |
Their first encounter with Jupiter would be two years | 0:04:44 | 0:04:47 | |
and half a billion miles away. | 0:04:47 | 0:04:49 | |
The two spacecraft were now heading on their epic journey. | 0:04:52 | 0:04:55 | |
But the story of the Voyager mission began almost 20 years earlier. | 0:04:57 | 0:05:01 | |
To uncover its origins, I've come to California, | 0:05:09 | 0:05:12 | |
to find out how it all started. | 0:05:12 | 0:05:14 | |
Today, it's really easy to take the successes of these remarkable | 0:05:19 | 0:05:23 | |
missions for granted, but in the years preceding Voyager, | 0:05:23 | 0:05:26 | |
simply getting to the outer planets was thought to be impossible. | 0:05:26 | 0:05:30 | |
The first object launched into orbit was Sputnik 1. | 0:05:34 | 0:05:39 | |
And from then on, space scientists became obsessed with journeying | 0:05:42 | 0:05:46 | |
ever further from Earth, exploring the far reaches of our solar system. | 0:05:46 | 0:05:51 | |
Yet no spacecraft could get much further than Mars... | 0:05:53 | 0:05:57 | |
and even that was a struggle. | 0:05:57 | 0:05:59 | |
The simple fact was we just didn't have a rocket | 0:05:59 | 0:06:01 | |
that was powerful enough to actually to be able | 0:06:01 | 0:06:04 | |
to escape the gravitational pull | 0:06:04 | 0:06:06 | |
of the sun and be able to get to the outer solar system. | 0:06:06 | 0:06:09 | |
And even if we did, the vast distances involved would mean | 0:06:09 | 0:06:13 | |
that a trip to Neptune would take half a lifetime - 30 or 40 years. | 0:06:13 | 0:06:18 | |
The outer planets were simply out of reach. | 0:06:18 | 0:06:21 | |
But back in 1961, here in California, | 0:06:26 | 0:06:30 | |
one man thought he might know how to bring these planets into reach. | 0:06:30 | 0:06:35 | |
He was a brilliant maths graduate, and his name was Michael Minovitch. | 0:06:35 | 0:06:41 | |
My father taught me how to do arithmetic | 0:06:41 | 0:06:44 | |
when I was like in 4th or 5th grade. | 0:06:44 | 0:06:47 | |
And then I learned the language - the secret of science. | 0:06:47 | 0:06:51 | |
And the secret of science is mathematics. | 0:06:51 | 0:06:54 | |
At the age of only 25, while he was still studying | 0:06:57 | 0:07:00 | |
for his PhD at UCLA, Minovitch set himself the challenge | 0:07:00 | 0:07:04 | |
of solving the most difficult problem in space exploration. | 0:07:04 | 0:07:08 | |
It was a puzzle that had stumped the world's greatest | 0:07:10 | 0:07:14 | |
mathematicians for centuries. | 0:07:14 | 0:07:17 | |
It's called the "three-body problem" - | 0:07:17 | 0:07:19 | |
body one, body two and body three. | 0:07:19 | 0:07:24 | |
And it involves the fiendishly complicated task of trying | 0:07:24 | 0:07:28 | |
to plot the trajectory of a small object, | 0:07:28 | 0:07:31 | |
ie a spacecraft, as it moves throughout the solar system, | 0:07:31 | 0:07:35 | |
whilst at the same time being deflected by the gravitational pull | 0:07:35 | 0:07:39 | |
of two much more massive objects, | 0:07:39 | 0:07:41 | |
ie the sun and a planet. | 0:07:41 | 0:07:44 | |
A solution to the three-body problem, | 0:07:47 | 0:07:49 | |
the ability to predict exactly how a spacecraft passing a planet | 0:07:49 | 0:07:54 | |
would have its path affected, was still beyond science... | 0:07:54 | 0:07:58 | |
until, that is, the young Minovitch came along. | 0:07:58 | 0:08:02 | |
It would have been regarded as impossibility | 0:08:03 | 0:08:06 | |
prior to what I did in 1961. | 0:08:06 | 0:08:09 | |
I was gifted being at a university that had | 0:08:16 | 0:08:19 | |
the 7090 computer, so that was the key. | 0:08:19 | 0:08:24 | |
UCLA's state-of-the-art IBM computer | 0:08:24 | 0:08:27 | |
was the fastest on Earth at the time, | 0:08:27 | 0:08:29 | |
and Minovitch put it to good use. | 0:08:29 | 0:08:33 | |
He began calculating thousands of alternative directions | 0:08:33 | 0:08:36 | |
and speeds, in an attempt to home in on the solution. | 0:08:36 | 0:08:42 | |
It was a long shot - not only for the young student | 0:08:42 | 0:08:45 | |
but also the university. | 0:08:45 | 0:08:48 | |
Working on a 7090 was costing 1,000 an hour, | 0:08:48 | 0:08:53 | |
so they were dumping bushels of money into a fantastic belief | 0:08:53 | 0:09:00 | |
and what was the belief? | 0:09:00 | 0:09:01 | |
Belief that a person that hadn't got his PhD | 0:09:01 | 0:09:05 | |
solved the problem that all the most advanced mathematicians in history | 0:09:05 | 0:09:10 | |
couldn't solve. That meant pressure on me, and so I thought to myself, | 0:09:10 | 0:09:15 | |
"How could I...? | 0:09:15 | 0:09:16 | |
"I can't live with myself, given this gift, knowing that there's | 0:09:16 | 0:09:20 | |
"a very strong possibility that my trajectories were not correct." | 0:09:20 | 0:09:24 | |
Minovitch went to the people with the most accurate data on the solar system at the time - | 0:09:30 | 0:09:35 | |
NASA's Jet Propulsion Laboratory in Pasadena. | 0:09:35 | 0:09:38 | |
They would decide if he had solved the three-body problem | 0:09:41 | 0:09:45 | |
or just wasted a lot of the university's money. | 0:09:45 | 0:09:48 | |
They ran the tests, about four or five different trajectory types, | 0:09:49 | 0:09:54 | |
different encounters, | 0:09:54 | 0:09:55 | |
and found every single one converged to the exact solution. | 0:09:55 | 0:10:00 | |
It was a beautiful moment in mathematics. | 0:10:07 | 0:10:10 | |
By solving the three-body problem, Minovitch had discovered a way | 0:10:10 | 0:10:14 | |
to use gravity to propel a spacecraft further and faster than ever before. | 0:10:14 | 0:10:19 | |
What Minovitch realised was, | 0:10:22 | 0:10:24 | |
as a spacecraft approaches the planet, | 0:10:24 | 0:10:27 | |
it gets pulled in by its gravity, | 0:10:27 | 0:10:29 | |
and as long as it doesn't crash into the planet, | 0:10:29 | 0:10:31 | |
because the planet is orbiting the sun at tens of thousands of kilometres an hour, | 0:10:31 | 0:10:38 | |
that spacecraft can take some of that energy and use it to get | 0:10:38 | 0:10:42 | |
catapulted out at an increased speed further out into the solar system. | 0:10:42 | 0:10:48 | |
With his new slingshot technique, | 0:10:51 | 0:10:53 | |
Minovitch had opened a gateway | 0:10:53 | 0:10:56 | |
to the outer planets, at least theoretically. | 0:10:56 | 0:10:58 | |
He identified hundreds of possible missions | 0:11:01 | 0:11:04 | |
to the planets, meticulously drawing them up in his notebooks. | 0:11:04 | 0:11:08 | |
The concept that I invented, | 0:11:10 | 0:11:12 | |
and I can show you the printout, if you look here, | 0:11:12 | 0:11:16 | |
you'll see there was no limit. | 0:11:16 | 0:11:18 | |
I could have a sequence that was a 100 planets long, | 0:11:18 | 0:11:21 | |
nonstop, planet to planet to planet, launched from Earth. | 0:11:21 | 0:11:26 | |
And then you come to Jupiter. Jupiter, you get a nice big bounce | 0:11:26 | 0:11:29 | |
and you use that to propel yourself to Saturn, and then Saturn is | 0:11:29 | 0:11:34 | |
a pretty darn big planet, and that will catapult you out to Pluto. | 0:11:34 | 0:11:38 | |
This concept could be used to explore the whole solar system | 0:11:38 | 0:11:43 | |
with one launch vehicle at one time | 0:11:43 | 0:11:46 | |
without any rocket propulsion at all. | 0:11:46 | 0:11:48 | |
But buried amongst those hundreds of theoretical | 0:11:53 | 0:11:55 | |
flight paths was one very special trajectory. | 0:11:55 | 0:12:00 | |
And no-one, not even Minovitch, noticed its significance. | 0:12:02 | 0:12:06 | |
In the summer of 1965, | 0:12:09 | 0:12:10 | |
right here at NASA's JPL, another vacation student was hired | 0:12:10 | 0:12:15 | |
to number-crunch the options for a mission to the outer planets. | 0:12:15 | 0:12:18 | |
And his name was Gary Flandro. | 0:12:18 | 0:12:20 | |
I was a summer student working on my degree at the time, | 0:12:22 | 0:12:26 | |
so when I was given the job of looking at the outer planets, | 0:12:26 | 0:12:30 | |
I thought that was kind of make-work project - | 0:12:30 | 0:12:33 | |
I was being kind of kept out of the way. | 0:12:33 | 0:12:35 | |
Flandro was a young engineer, grounded in the hard realities | 0:12:38 | 0:12:42 | |
of spaceflight, and he began to look at whether | 0:12:42 | 0:12:46 | |
a solution to the three-body problem could be put to practical use. | 0:12:46 | 0:12:50 | |
Obviously, the first thing is to determine | 0:12:56 | 0:12:59 | |
when the planets are going to be in positions where we could reach them. | 0:12:59 | 0:13:03 | |
So I drew very careful maps of where the planets would be, | 0:13:03 | 0:13:08 | |
and one of the most important drawings was one in which | 0:13:08 | 0:13:11 | |
I drew the positions of the planets versus the date. | 0:13:11 | 0:13:14 | |
And the thing that caught my attention immediately was | 0:13:14 | 0:13:19 | |
that the lines for Jupiter, Saturn, Uranus and Neptune | 0:13:19 | 0:13:22 | |
all crossed in about the 1975-76 time period. | 0:13:22 | 0:13:26 | |
In other words, those four major planets were on the same side of the sun | 0:13:26 | 0:13:30 | |
and in the same general position at the same time. | 0:13:30 | 0:13:33 | |
So it gave me the idea immediately that we could do | 0:13:33 | 0:13:36 | |
all of those planets with one flight. | 0:13:36 | 0:13:38 | |
This narrow window - to slingshot from one planet straight | 0:13:40 | 0:13:44 | |
to the next - would not open again for another 176 years. | 0:13:44 | 0:13:49 | |
It was too good an opportunity to miss. | 0:13:49 | 0:13:52 | |
And so was born the idea of a Grand Tour, | 0:13:58 | 0:14:01 | |
the most ambitious space mission of its time. | 0:14:01 | 0:14:04 | |
It would send two identical space probes to all four | 0:14:04 | 0:14:08 | |
of the solar system's outer planets in one relatively short flight. | 0:14:08 | 0:14:12 | |
Such encounters promised spectacular views of these distant worlds, | 0:14:13 | 0:14:17 | |
planets we only knew as blurry objects through telescopes. | 0:14:17 | 0:14:20 | |
The half billion miles to Jupiter would take two years. | 0:14:22 | 0:14:25 | |
Then another two years to Saturn... | 0:14:27 | 0:14:29 | |
..five more to Uranus | 0:14:31 | 0:14:34 | |
and a final three to reach Neptune. | 0:14:34 | 0:14:37 | |
It meant the Voyagers would need to function for at least 12 years. | 0:14:40 | 0:14:46 | |
Yet NASA had never built a spacecraft guaranteed to last | 0:14:46 | 0:14:50 | |
longer than a few months. | 0:14:50 | 0:14:52 | |
It was their biggest challenge yet. | 0:14:52 | 0:14:55 | |
Hi, John, how are you? | 0:14:58 | 0:14:59 | |
Oh, Dallas, I'm fine. Thanks for coming. | 0:14:59 | 0:15:02 | |
And it was one which fell to a young engineer called John Casani. | 0:15:02 | 0:15:06 | |
The issue was the time. It takes time to cover that distance. | 0:15:09 | 0:15:13 | |
You're going a long ways, and that takes time, | 0:15:13 | 0:15:15 | |
and the time is...can you make all these machines operate | 0:15:15 | 0:15:18 | |
without human intervention or adjustment? | 0:15:18 | 0:15:20 | |
Well, I mean... | 0:15:20 | 0:15:21 | |
At that point in time, that was a mind-blowing thought - | 0:15:21 | 0:15:25 | |
how you build a spacecraft that can survive failures | 0:15:25 | 0:15:28 | |
and still keep on chugging? | 0:15:28 | 0:15:31 | |
Five years of testing and redesigning followed, | 0:15:31 | 0:15:34 | |
as NASA's engineers grappled with the task of building | 0:15:34 | 0:15:38 | |
a spacecraft capable of the job. | 0:15:38 | 0:15:41 | |
And they needed to do it before 1977, | 0:15:41 | 0:15:45 | |
when the launch window for this Grand Tour would close... | 0:15:45 | 0:15:49 | |
at least for another 176 years. | 0:15:49 | 0:15:52 | |
The thing that was scary was that it was going to be based | 0:15:52 | 0:15:56 | |
on a lot of new technology, so it was a technological leap. | 0:15:56 | 0:16:01 | |
We thought we could do it - nobody else did. | 0:16:02 | 0:16:05 | |
They'd cracked the mathematics, | 0:16:08 | 0:16:11 | |
they were confident tackling the technology, | 0:16:11 | 0:16:13 | |
but there was one more thing they needed - money. | 0:16:13 | 0:16:17 | |
NASA still lacked the funding to support the mission beyond Saturn. | 0:16:17 | 0:16:21 | |
To ensure further funding, the public and Congress would need | 0:16:21 | 0:16:25 | |
regular reminders of their achievements. | 0:16:25 | 0:16:29 | |
The Voyagers needed a voice, someone who could turn their saga of | 0:16:29 | 0:16:33 | |
celestial exploration into something that all Americans could share. | 0:16:33 | 0:16:37 | |
They turned to a young member of the Voyager team | 0:16:37 | 0:16:41 | |
with a passion for storytelling - | 0:16:41 | 0:16:43 | |
his name was Carl Sagan. | 0:16:43 | 0:16:45 | |
Wouldn't it be lovely | 0:16:45 | 0:16:47 | |
to make contact with another civilisation | 0:16:47 | 0:16:50 | |
that has arisen and evolved independently? | 0:16:50 | 0:16:53 | |
Aware that the Voyagers would head away from us forever, | 0:16:53 | 0:16:57 | |
Sagan proposed an extraordinary idea. | 0:16:57 | 0:17:01 | |
On board each spacecraft, he suggested placing | 0:17:01 | 0:17:04 | |
a message from Earth - | 0:17:04 | 0:17:07 | |
an idea which would capture public imagination. | 0:17:07 | 0:17:10 | |
Attached to each spacecraft is a fairly elaborate message | 0:17:10 | 0:17:15 | |
in the form of a phonograph record and instructions for playing. | 0:17:15 | 0:17:19 | |
It was a gold-plated copper record - | 0:17:19 | 0:17:21 | |
a gift of recordings and greetings | 0:17:21 | 0:17:24 | |
from the inhabitants of this planet to those of some other. | 0:17:24 | 0:17:29 | |
'Bonjour, tout le monde...' | 0:17:30 | 0:17:32 | |
GREETINGS IN JAPANESE AND RUSSIAN | 0:17:32 | 0:17:35 | |
Each disc contained a combination of sounds | 0:17:35 | 0:17:38 | |
and pictures and above all music - | 0:17:38 | 0:17:41 | |
from Chuck Berry to Azerbaijani bagpipes and Johann Sebastian Bach. | 0:17:41 | 0:17:46 | |
Sagan argued that sometime, somewhere, | 0:17:48 | 0:17:52 | |
another civilisation may find one of the Voyagers. | 0:17:52 | 0:17:55 | |
The record's purpose was to tell them | 0:17:55 | 0:17:57 | |
what kind of creatures had sent it. | 0:17:57 | 0:18:01 | |
How much will they know about us, what we're really like? | 0:18:01 | 0:18:05 | |
To communicate that, music is a way of expression of human feelings, | 0:18:05 | 0:18:11 | |
desires, passions, hopes. | 0:18:11 | 0:18:14 | |
In some sense, all the performers | 0:18:14 | 0:18:16 | |
and composers on this record will live forever. | 0:18:16 | 0:18:19 | |
With their golden records on board, | 0:18:19 | 0:18:22 | |
and the public's imagination fired up, the Grand Tour was underway. | 0:18:22 | 0:18:27 | |
But no-one could know if the mission was going to deliver results | 0:18:27 | 0:18:30 | |
until the Voyagers reached their first planet, | 0:18:30 | 0:18:34 | |
and that would take two long years. | 0:18:34 | 0:18:38 | |
April 1979, and two years after launch, Mission Control was steering | 0:18:50 | 0:18:56 | |
the Voyagers towards their first rendezvous. | 0:18:56 | 0:18:59 | |
It was with the largest planet in our solar system - Jupiter. | 0:18:59 | 0:19:03 | |
Before Voyager, the best images astronomers had of | 0:19:08 | 0:19:11 | |
Jupiter and its moons were fuzzy photographs. | 0:19:11 | 0:19:15 | |
Could the Voyagers change all that? | 0:19:15 | 0:19:18 | |
I think we all felt that we were in the tradition of Galileo, | 0:19:18 | 0:19:21 | |
who was the first to see the moons of Jupiter, | 0:19:21 | 0:19:24 | |
and the first to apply an instrument | 0:19:24 | 0:19:27 | |
to increase our ability to observe the universe. | 0:19:27 | 0:19:30 | |
Voyager was just the latest tool which we, as a civilisation, | 0:19:30 | 0:19:35 | |
had managed to devise. | 0:19:35 | 0:19:36 | |
And, of course, the tool was so powerful that we saw things | 0:19:36 | 0:19:40 | |
nobody had seen before and that nobody had imagined we would see. | 0:19:40 | 0:19:43 | |
For the man who'd first proposed the mission, it was a thrilling moment. | 0:19:44 | 0:19:49 | |
That first encounter with Jupiter was a marvellous... | 0:19:49 | 0:19:52 | |
time for me, especially the approach shots showing the planet | 0:19:52 | 0:19:56 | |
revolving and watching the great red spot revolving getting closer | 0:19:56 | 0:19:59 | |
and closer till finally we could see that indeed this was | 0:19:59 | 0:20:04 | |
the top of a large storm. | 0:20:04 | 0:20:06 | |
As a child, I had studied that and wondered if that was a storm | 0:20:06 | 0:20:10 | |
or was that an island floating in an ocean - | 0:20:10 | 0:20:12 | |
it was very difficult to know - | 0:20:12 | 0:20:13 | |
and, finally, the answers were there before our eyes. | 0:20:13 | 0:20:16 | |
At the time, Voyager scientist Andy Ingersoll revealed | 0:20:18 | 0:20:21 | |
these discoveries to a BBC Horizon crew. | 0:20:21 | 0:20:25 | |
The movie here shows pictures of Jupiter taken every ten hours. | 0:20:25 | 0:20:29 | |
The shutter was snapped, | 0:20:29 | 0:20:31 | |
then this is played in a sequence over and over again | 0:20:31 | 0:20:33 | |
so you can see motion. | 0:20:33 | 0:20:36 | |
And this rapid mixing makes the existence of permanent | 0:20:36 | 0:20:39 | |
different-coloured, different chemical features | 0:20:39 | 0:20:42 | |
even more mysterious. | 0:20:42 | 0:20:44 | |
See, I'm a weather man, I'm an atmospheric scientist, | 0:20:48 | 0:20:51 | |
and we knew about the 300-year-old storms, the great red spot, | 0:20:51 | 0:20:55 | |
because people had been looking at it from Earth, | 0:20:55 | 0:20:58 | |
and for me the surprise was, when we got up close, | 0:20:58 | 0:21:01 | |
we saw that the atmosphere was just churning and turbulent, | 0:21:01 | 0:21:04 | |
and it made this 300-year-old storm all the more mysterious, | 0:21:04 | 0:21:09 | |
cos how could it go on in the midst of all this turbulence? | 0:21:09 | 0:21:14 | |
We all approached Jupiter with great expectation | 0:21:16 | 0:21:19 | |
and we all had our grandiose theories about what we were | 0:21:19 | 0:21:22 | |
going to see, but, of course, Jupiter fooled us all. | 0:21:22 | 0:21:25 | |
There was some bizarre behaviour. | 0:21:25 | 0:21:28 | |
Little clouds moving along and being swept up in the great red spot | 0:21:28 | 0:21:31 | |
and then being... | 0:21:31 | 0:21:33 | |
it would spit them out again. | 0:21:33 | 0:21:34 | |
Other clouds would roll along next to one another, | 0:21:36 | 0:21:39 | |
coalesce into a single cloud and then break apart again. | 0:21:39 | 0:21:42 | |
Voyager's pictures suggested that Jupiter's wildly churning atmosphere | 0:21:47 | 0:21:52 | |
seemed to be driven by heat from deep within the planet. | 0:21:52 | 0:21:56 | |
Scientists speculated that it came from a hot, | 0:21:57 | 0:21:59 | |
high-pressure core of metallic hydrogen. | 0:21:59 | 0:22:03 | |
Such a centre also seemed to be powering an immense magnetic field, | 0:22:05 | 0:22:09 | |
10,000 times stronger than Earth's, | 0:22:09 | 0:22:12 | |
and for the Voyagers, that was a problem, | 0:22:12 | 0:22:16 | |
because this magnetism creates lethal radiation belts, | 0:22:16 | 0:22:20 | |
which can scramble the computers of any spacecraft that gets too close. | 0:22:20 | 0:22:24 | |
Yet getting close was exactly what was needed. | 0:22:30 | 0:22:34 | |
The Voyager team wanted to send Voyager 1 to explore Io, | 0:22:34 | 0:22:38 | |
one of Jupiter's four largest moons, | 0:22:38 | 0:22:41 | |
and it was the nearest of all of them to the planet. | 0:22:41 | 0:22:44 | |
The spacecraft was designed to withstand | 0:22:44 | 0:22:47 | |
a certain total dose of radiation, and fully 50% of that expected dose | 0:22:47 | 0:22:52 | |
was going to occur as we approached and flew by Io. | 0:22:52 | 0:22:56 | |
As Voyager 1 approached, | 0:23:02 | 0:23:04 | |
it sent back recordings of the radio signal generated by the radiation. | 0:23:04 | 0:23:08 | |
LOUD, DISTORTED WHISTLES | 0:23:08 | 0:23:11 | |
These are the real sounds of the onslaught. | 0:23:13 | 0:23:16 | |
Back at JPL, the Voyager team worried whether it could withstand | 0:23:23 | 0:23:27 | |
such an assault, and whether the gamble would pay off. | 0:23:27 | 0:23:32 | |
Voyager navigation engineer Linda Hyder was the first to find out. | 0:23:34 | 0:23:40 | |
I came in about nine o'clock that morning to the navigation area, | 0:23:40 | 0:23:44 | |
and the tape with the pictures the spacecraft had taken | 0:23:44 | 0:23:47 | |
the day before was on my desk. | 0:23:47 | 0:23:49 | |
I put them on the computer system and I displayed them. | 0:23:49 | 0:23:53 | |
And I could see that Io, the moon of Io, was a crescent, | 0:23:53 | 0:23:56 | |
as very often our own moon is a crescent in the night sky, | 0:23:56 | 0:24:00 | |
and I went and enhanced the brightness, | 0:24:00 | 0:24:02 | |
and there appeared beside Io an object, a huge object, | 0:24:02 | 0:24:06 | |
and it completely captured my attention. | 0:24:06 | 0:24:09 | |
It looked like another moon peeking out from behind Io. | 0:24:12 | 0:24:15 | |
But there was no other moon and no fault in the camera. | 0:24:19 | 0:24:24 | |
Linda decided this object had to be part of Io. | 0:24:24 | 0:24:28 | |
And, in fact, that was very hard to accept, | 0:24:28 | 0:24:32 | |
because the size of this object was enormous. | 0:24:32 | 0:24:34 | |
And when I explored it, | 0:24:44 | 0:24:46 | |
I was able to find that this large, strange object, | 0:24:46 | 0:24:49 | |
it was exactly coincident and fell over a heart-shaped feature on Io. | 0:24:49 | 0:24:54 | |
What I had discovered was the huge plume of a volcanic eruption, | 0:24:54 | 0:24:59 | |
arising 270km over the surface of Io and raining back down onto it. | 0:24:59 | 0:25:04 | |
So I had discovered the first-ever volcanic eruption ever seen | 0:25:08 | 0:25:12 | |
on another world besides the Earth. | 0:25:12 | 0:25:15 | |
The gamble of being exposed to such radiation had paid off. | 0:25:21 | 0:25:25 | |
Voyager 1 had revealed that Io, | 0:25:25 | 0:25:29 | |
the closest of Jupiter's large moons, | 0:25:29 | 0:25:31 | |
was more geologically active than the Earth. | 0:25:31 | 0:25:34 | |
Jupiter's enormous gravity stretches and squeezes the moon, | 0:25:34 | 0:25:39 | |
forcing its core to heat up and its interior to stay molten. | 0:25:39 | 0:25:43 | |
We found that Io had eight active volcanoes on it, | 0:25:43 | 0:25:47 | |
the most volcanically active body in the solar system, | 0:25:47 | 0:25:50 | |
and it's just a small moon, and that was so unexpected. | 0:25:50 | 0:25:54 | |
And it was such a shift in our paradigm | 0:25:54 | 0:25:57 | |
about what was going on in the outer solar system | 0:25:57 | 0:26:00 | |
where it's very cold and, presumably, we thought very dead. | 0:26:00 | 0:26:03 | |
So in that sense, it characterised for us | 0:26:03 | 0:26:07 | |
the sense of seeing things that we really hadn't thought about, | 0:26:07 | 0:26:10 | |
and that was in fact very characteristic | 0:26:10 | 0:26:12 | |
of the rest of the mission. | 0:26:12 | 0:26:14 | |
And that wasn't all. | 0:26:19 | 0:26:20 | |
As the Voyagers flew by Jupiter's other moons, | 0:26:20 | 0:26:24 | |
more discoveries began pouring in. | 0:26:24 | 0:26:26 | |
These exotic satellite worlds of rock and ice needed | 0:26:26 | 0:26:31 | |
a new expertise to interpret them. | 0:26:31 | 0:26:34 | |
The Voyager team had to react quickly, | 0:26:34 | 0:26:36 | |
bringing on board more planetary geologists. | 0:26:36 | 0:26:40 | |
There's a twin, a pair there, and then there's... | 0:26:40 | 0:26:42 | |
What about the relief from the cracks? Shouldn't the cracks... | 0:26:42 | 0:26:46 | |
In order for there... | 0:26:46 | 0:26:48 | |
'All of the scientists, with the exception | 0:26:48 | 0:26:50 | |
'of me, were atmospheric scientists and astronomers.' | 0:26:50 | 0:26:52 | |
And, in fact, it wasn't until we really recognised the exotic variety | 0:26:52 | 0:26:57 | |
and diversity of the satellites, | 0:26:57 | 0:26:59 | |
that geologists were really added to the Voyager team. | 0:26:59 | 0:27:03 | |
And in fact the satellites, in my view, | 0:27:05 | 0:27:06 | |
became the star of the whole Voyager experience. | 0:27:06 | 0:27:09 | |
Voyager's encounter with Jupiter was a triumph, | 0:27:15 | 0:27:18 | |
and Carl Sagan hosted a televised evening to celebrate. | 0:27:18 | 0:27:22 | |
It's impossible to look at these pictures with only | 0:27:23 | 0:27:27 | |
a scientific cast of mind, because they are simply exquisite. | 0:27:27 | 0:27:31 | |
And this is part of the remarkable historical transition, | 0:27:31 | 0:27:36 | |
which is happening in the late 20th century in which we are, | 0:27:36 | 0:27:39 | |
for the first time, learning the realities, not the myths, | 0:27:39 | 0:27:43 | |
of our little swimming hole in space. | 0:27:43 | 0:27:47 | |
On a night like tonight, our eyes, our minds, our souls, | 0:27:47 | 0:27:52 | |
our blood are moving out through the universe. | 0:27:52 | 0:27:55 | |
We're part of history, | 0:27:56 | 0:27:58 | |
and that means that we have to replace the old myths with new ones. | 0:27:58 | 0:28:02 | |
With Jupiter behind them, the two Voyager spacecraft headed | 0:28:05 | 0:28:09 | |
further out into interplanetary space. | 0:28:09 | 0:28:12 | |
It would be more than two years | 0:28:15 | 0:28:16 | |
before they reached the next destination | 0:28:16 | 0:28:18 | |
on their Grand Tour - the planet Saturn, almost a billion miles away. | 0:28:18 | 0:28:24 | |
The technology and engineering needed to accomplish | 0:28:26 | 0:28:29 | |
such long-distance, long-duration spaceflight, was truly remarkable. | 0:28:29 | 0:28:35 | |
The spacecraft needed to be designed to cope with anything | 0:28:35 | 0:28:39 | |
their multi-billion-mile journey would throw at them. | 0:28:39 | 0:28:42 | |
Luckily, you don't need to travel 11 billion miles to | 0:28:43 | 0:28:46 | |
get up close and personal and really appreciate the | 0:28:46 | 0:28:49 | |
extraordinary engineering of Voyager, | 0:28:49 | 0:28:51 | |
because there's another one a little bit closer to home. | 0:28:51 | 0:28:54 | |
When JPL built the Voyagers, | 0:28:56 | 0:28:59 | |
they also assembled a couple of extra models from flight spares, | 0:28:59 | 0:29:03 | |
as an Earth-bound reminder of their visionary 1970s technology. | 0:29:03 | 0:29:07 | |
Dominating the entire structure is this great communications dish | 0:29:22 | 0:29:27 | |
that's beaming back to Earth all that data that the Voyager | 0:29:27 | 0:29:30 | |
spacecrafts collect across billions of miles of empty space. | 0:29:30 | 0:29:35 | |
Incredibly, the power of this signal was designed to be a mere 20 watts - | 0:29:35 | 0:29:40 | |
about the same as a fridge light bulb. | 0:29:40 | 0:29:43 | |
And situated on this arm, | 0:29:43 | 0:29:45 | |
quite sensibly far away from the spacecraft, | 0:29:45 | 0:29:47 | |
is Voyager's power supply. | 0:29:47 | 0:29:49 | |
It's a plutonium-fuelled generator that can power the spacecraft | 0:29:49 | 0:29:54 | |
in deep space when solar power just isn't an option. | 0:29:54 | 0:29:57 | |
And over on the other side, sticking out on another boom, | 0:29:58 | 0:30:01 | |
perhaps most excitingly, this is Voyager's eyes. | 0:30:01 | 0:30:05 | |
This great collection of cameras that revealed | 0:30:05 | 0:30:07 | |
new worlds for the first time, | 0:30:07 | 0:30:09 | |
and let us see the solar system with greater clarity than ever before. | 0:30:09 | 0:30:13 | |
1981, and two years on from the stunning images of Jupiter, | 0:30:17 | 0:30:22 | |
the public were queuing up to get their first clear views | 0:30:22 | 0:30:26 | |
of the mysterious ringed planet, Saturn. | 0:30:26 | 0:30:29 | |
MUSIC: More Than A Feeling by Boston | 0:30:29 | 0:30:32 | |
The Voyager team had prepared in meticulous detail for the encounter, | 0:30:37 | 0:30:42 | |
as they knew they had just a tiny window to get it right. | 0:30:42 | 0:30:46 | |
Each spacecraft would fly by so quickly, | 0:30:46 | 0:30:49 | |
on such a close approach, there was almost no time to gather data. | 0:30:49 | 0:30:54 | |
The closest approach fly-by sequences are a matter of hours. | 0:30:54 | 0:31:00 | |
Really, the tightest closest approach activity is within a 12-hour span. | 0:31:00 | 0:31:04 | |
In particular, the team needed to decide where to point the cameras. | 0:31:08 | 0:31:13 | |
The scan platform, which included the cameras | 0:31:13 | 0:31:16 | |
and spectrometers, am I going to point it at the moon | 0:31:16 | 0:31:19 | |
and which moon, or am I going to point it at the planet? | 0:31:19 | 0:31:22 | |
Which way am I going to point it? | 0:31:22 | 0:31:24 | |
And so you have to argue with your colleagues. | 0:31:24 | 0:31:28 | |
Blue-ish. Blue-er than grey. | 0:31:28 | 0:31:33 | |
But it was the rings of Saturn which stole the show. | 0:31:35 | 0:31:39 | |
We thought we knew it all, | 0:31:39 | 0:31:41 | |
but, once again, we were looking at a very, very complex situation. | 0:31:41 | 0:31:46 | |
The rings were broken up into mini-rings. | 0:31:46 | 0:31:48 | |
There were gaps in there, | 0:31:48 | 0:31:50 | |
there were all sorts of dynamical phenomena that we didn't understand. | 0:31:50 | 0:31:54 | |
When I began my work, I had suggested that one thing | 0:32:06 | 0:32:09 | |
we could do with this particular mission was | 0:32:09 | 0:32:12 | |
to fly between the planet and the rings, | 0:32:12 | 0:32:15 | |
and, very fortunately, we didn't do that, | 0:32:15 | 0:32:17 | |
because, as we approached Saturn, | 0:32:17 | 0:32:19 | |
we saw that the region there we would have had to flown through with the spacecraft | 0:32:19 | 0:32:23 | |
was filled with more rings. | 0:32:23 | 0:32:24 | |
There was no question - that spacecraft would not have survived | 0:32:24 | 0:32:28 | |
trying to go through that gap. | 0:32:28 | 0:32:30 | |
The imaging team could barely cope with all the new data. | 0:32:32 | 0:32:36 | |
What I remember...it wasn't really stressful, | 0:32:40 | 0:32:44 | |
but it was just chaotic and hectic and exciting. | 0:32:44 | 0:32:47 | |
Right in the few days around the encounter, trying to keep up | 0:32:47 | 0:32:51 | |
with the discoveries as they poured in. | 0:32:51 | 0:32:55 | |
Eventually, no-one got any sleep, | 0:32:55 | 0:32:57 | |
because we were just overwhelmed with new stuff. | 0:32:57 | 0:33:00 | |
Voyager revealed delicate rings that were intertwined | 0:33:04 | 0:33:07 | |
and rings that were held in place by tiny moons they called shepherds. | 0:33:07 | 0:33:13 | |
There were strange features called spokes, | 0:33:13 | 0:33:16 | |
patches of dust particles, slightly raised above the rings. | 0:33:16 | 0:33:21 | |
These caught the eye of one young graduate student in particular. | 0:33:21 | 0:33:24 | |
I got involved in the study of the spokes, | 0:33:27 | 0:33:29 | |
which were these ghostly features that were seen to come and go, | 0:33:29 | 0:33:33 | |
and it just came to my head to kind of categorise the pictures. | 0:33:33 | 0:33:37 | |
Into one pile, I put all those images that seemed to have | 0:33:37 | 0:33:40 | |
a lot of spokes in them, | 0:33:40 | 0:33:42 | |
and into another pile, I put those images | 0:33:42 | 0:33:44 | |
that seemed to have virtually no spokes at all. | 0:33:44 | 0:33:47 | |
And I made an intermediate category. | 0:33:47 | 0:33:49 | |
And, of course, each image was tagged with a time, | 0:33:49 | 0:33:52 | |
and I basically did an analysis on the computer of this | 0:33:52 | 0:33:56 | |
and found that the spokes actually weren't just sporadic but, in fact, | 0:33:56 | 0:34:02 | |
they came and went with a certain period. | 0:34:02 | 0:34:04 | |
Remarkably, Carolyn Porco had discovered that the spokes | 0:34:14 | 0:34:18 | |
followed Saturn's magnetic field as it rotated with the planet. | 0:34:18 | 0:34:24 | |
I made my very first scientific discovery, and just knowing that | 0:34:24 | 0:34:30 | |
I had found something that nobody else on the face of the planet knew | 0:34:30 | 0:34:33 | |
at that time was just such an exhilarating experience. | 0:34:33 | 0:34:37 | |
Well, I think Saturn has not disappointed us. | 0:34:42 | 0:34:44 | |
I really expected that since we had such a rudimentary | 0:34:44 | 0:34:47 | |
knowledge of Saturn system that we would be seeing many surprises, | 0:34:47 | 0:34:51 | |
but, as usual, our imaginations were not nearly up to | 0:34:51 | 0:34:54 | |
what nature provided. | 0:34:54 | 0:34:56 | |
Four years since launch, the Voyagers had, | 0:35:00 | 0:35:04 | |
so far, been a wild success. | 0:35:04 | 0:35:07 | |
But now came the mission planner's biggest gamble. | 0:35:07 | 0:35:11 | |
Here at Saturn, the twin spacecraft would part company. | 0:35:11 | 0:35:15 | |
Voyager 1 would be diverted towards Saturn's largest moon, Titan. | 0:35:17 | 0:35:21 | |
It was an enticing target. | 0:35:22 | 0:35:24 | |
It was clear that the composition of Titan's atmosphere | 0:35:26 | 0:35:29 | |
makes it kind of an analogue with the Earth, | 0:35:29 | 0:35:32 | |
which is terribly surprising, because no-one expected years ago | 0:35:32 | 0:35:35 | |
you'd find an analogue of the Earth out at the distance of Saturn. | 0:35:35 | 0:35:38 | |
With an atmosphere of similar density to Earth's, | 0:35:40 | 0:35:44 | |
it was believed Titan might even harbour primitive life. | 0:35:44 | 0:35:47 | |
But the manoeuvre came at great cost. | 0:35:49 | 0:35:52 | |
To fly past Titan, Voyager 1's Grand Tour | 0:35:52 | 0:35:55 | |
would have to be sacrificed. | 0:35:55 | 0:35:58 | |
To visit this intriguing moon, | 0:35:58 | 0:36:00 | |
it needed to be put on a different path, | 0:36:00 | 0:36:02 | |
throwing it up at an angle, out of the plane of the solar system. | 0:36:02 | 0:36:07 | |
Beyond Titan, there would be no more planetary encounters for Voyager 1. | 0:36:07 | 0:36:12 | |
In the end, the Titan fly-by was a disappointment. | 0:36:18 | 0:36:22 | |
Voyager 1's cameras couldn't penetrate its atmosphere | 0:36:22 | 0:36:25 | |
to offer further clues to whether life might lie beneath. | 0:36:25 | 0:36:28 | |
Titan was the first major setback for the Voyager team. | 0:36:31 | 0:36:34 | |
It meant Voyager 1 had been sacrificed for very little | 0:36:40 | 0:36:43 | |
and was now speeding away from the solar system. | 0:36:43 | 0:36:46 | |
The rest of the Grand Tour would have to rely on | 0:36:52 | 0:36:54 | |
one single spacecraft - | 0:36:54 | 0:36:57 | |
Voyager 2. | 0:36:57 | 0:36:59 | |
Now on its own, it was heading across the solar system | 0:36:59 | 0:37:02 | |
towards the outermost planets. | 0:37:02 | 0:37:04 | |
But then, just as it left Saturn, another setback - | 0:37:08 | 0:37:12 | |
the team noticed Voyager 2's camera platform had started to jam. | 0:37:12 | 0:37:16 | |
Without the crucial ability to pan its cameras, | 0:37:18 | 0:37:21 | |
there would be few pictures of the other outer planets. | 0:37:21 | 0:37:25 | |
It was a potential disaster, and the team struggled to find the cause. | 0:37:25 | 0:37:29 | |
In the case of the stuck scan platform, the expectation | 0:37:31 | 0:37:35 | |
was that there was a piece of debris, which is not likely. | 0:37:35 | 0:37:38 | |
I mean, we're so careful when we put these machines together. | 0:37:38 | 0:37:42 | |
So then it goes down to, well, maybe it's the lubricant, | 0:37:44 | 0:37:49 | |
the way the lubricant has distributed itself. | 0:37:49 | 0:37:52 | |
So how do you fix a spacecraft that's over a billion miles away? | 0:37:55 | 0:38:00 | |
What we decided to do was to exercise it very carefully, | 0:38:01 | 0:38:05 | |
moving the gears train back and forth slowly over this spot. | 0:38:05 | 0:38:08 | |
We could see that we were making progress and we said, | 0:38:10 | 0:38:12 | |
"OK, this is it. We can work through it". | 0:38:12 | 0:38:14 | |
But without any target to focus the cameras on, | 0:38:16 | 0:38:18 | |
they had no way to know if their fix was successful. | 0:38:18 | 0:38:23 | |
They'd only know that when Voyager 2 reached its next destination - | 0:38:23 | 0:38:28 | |
Uranus. | 0:38:28 | 0:38:29 | |
Even travelling at 50,000 miles an hour, | 0:38:29 | 0:38:32 | |
this encounter was five years away. | 0:38:32 | 0:38:35 | |
Half a decade of uncertainty and anxiety. | 0:38:38 | 0:38:42 | |
Well, just about two minutes ago, | 0:38:49 | 0:38:52 | |
Voyager 2 passed through its closest approach to Uranus. | 0:38:52 | 0:38:56 | |
APPLAUSE | 0:38:56 | 0:38:58 | |
Despite their fix to the scan platform, | 0:39:04 | 0:39:06 | |
with the limited light this far from the sun, | 0:39:06 | 0:39:09 | |
the Voyager team knew their cameras would struggle. | 0:39:09 | 0:39:13 | |
Voyager was planned to operate at 1 billion miles at Saturn. | 0:39:13 | 0:39:17 | |
It was now being asked to operate at 2 billion miles at Uranus, | 0:39:17 | 0:39:20 | |
where the sun was very dim, and we had to do several things. | 0:39:20 | 0:39:23 | |
For instance, you have to have much longer exposures on the camera, | 0:39:23 | 0:39:26 | |
and, if you have too long an exposure, | 0:39:26 | 0:39:27 | |
the spacecraft's moving very rapidly, things become smeared. | 0:39:27 | 0:39:31 | |
So we had to learn how to program the spacecraft | 0:39:31 | 0:39:34 | |
to turn at just the right rate, | 0:39:34 | 0:39:36 | |
so that it would compensate for the motion of the spacecraft. | 0:39:36 | 0:39:40 | |
They had to basically reprogram the brains of the spacecraft. | 0:39:44 | 0:39:49 | |
It didn't have very many brains by today's standards, | 0:39:49 | 0:39:51 | |
but they had to reprogram it. | 0:39:51 | 0:39:54 | |
Those were fantastic achievements. | 0:39:54 | 0:39:56 | |
As the first images of Uranus arrived back on Earth, | 0:39:58 | 0:40:02 | |
it became clear the engineers' ingenuity had once again paid off. | 0:40:02 | 0:40:08 | |
But the extraordinary, pin-sharp pictures of this distant planet, | 0:40:08 | 0:40:12 | |
two billion miles from Earth, revealed tantalisingly little. | 0:40:12 | 0:40:17 | |
After all the waiting, it was a reminder that with Voyager, | 0:40:17 | 0:40:22 | |
nothing could be taken for granted. | 0:40:22 | 0:40:25 | |
Uranus is different than Jupiter and Saturn | 0:40:25 | 0:40:27 | |
in the sense that it has no internal heat source. | 0:40:27 | 0:40:30 | |
Both Jupiter and Saturn are radiating more energy | 0:40:30 | 0:40:33 | |
than they receive from the sun, | 0:40:33 | 0:40:34 | |
because there's still heat inside those planets. | 0:40:34 | 0:40:37 | |
For a reason, at Uranus, that heat had been shut down | 0:40:37 | 0:40:40 | |
and was not driving the atmosphere, so the atmosphere was much blander. | 0:40:40 | 0:40:43 | |
Check... | 0:40:47 | 0:40:49 | |
If Uranus itself was something of a disappointment, | 0:40:53 | 0:40:57 | |
once again, the team found plenty of surprises in its moons. | 0:40:57 | 0:41:00 | |
Most striking of all was the tiny moon, Miranda. | 0:41:02 | 0:41:05 | |
Miranda looks like a three-dimensional jigsaw puzzle. | 0:41:08 | 0:41:12 | |
We see regions looking like giant, complex racetracks, | 0:41:12 | 0:41:15 | |
almost as if it's put together by a committee. | 0:41:15 | 0:41:19 | |
There are pieces stuck on the surface | 0:41:19 | 0:41:20 | |
that look like they belong to different planets, | 0:41:20 | 0:41:23 | |
and one idea was that it was busted apart | 0:41:23 | 0:41:26 | |
and these core pieces stayed intact, | 0:41:26 | 0:41:29 | |
and then they were glued back together, | 0:41:29 | 0:41:32 | |
and so you get this hodgepodge. | 0:41:32 | 0:41:34 | |
From Uranus, Voyager 2 faced it's final challenge - | 0:41:44 | 0:41:48 | |
the journey to Neptune, over a billion miles further out | 0:41:48 | 0:41:53 | |
and three years more space travel to survive. | 0:41:53 | 0:41:56 | |
The last major planet in the solar system, | 0:41:57 | 0:42:00 | |
this most mysterious world had resisted investigation | 0:42:00 | 0:42:04 | |
from even the most powerful telescopes. | 0:42:04 | 0:42:06 | |
To maintain its trajectory, | 0:42:11 | 0:42:13 | |
Voyager 2 needed to make a low pass over Neptune's north pole. | 0:42:13 | 0:42:17 | |
But this brought its own problems. | 0:42:18 | 0:42:20 | |
Because of increased speed and approach angle, | 0:42:20 | 0:42:23 | |
Voyager 2's window of opportunity would be the narrowest yet. | 0:42:23 | 0:42:27 | |
The challenge at Neptune was the most difficult one we had. | 0:42:31 | 0:42:36 | |
We had to know, within one second, | 0:42:36 | 0:42:38 | |
when we were going to fly over the north pole of Neptune. | 0:42:38 | 0:42:41 | |
That was a major navigational challenge - | 0:42:41 | 0:42:44 | |
we had never delivered that kind of accuracy before. | 0:42:44 | 0:42:47 | |
If we were right, it worked. | 0:42:47 | 0:42:49 | |
If we were wrong, we had no second chance. | 0:42:49 | 0:42:53 | |
Not only did the team need to position a spacecraft | 0:42:55 | 0:42:59 | |
to within a second of accuracy, after a flight of 12 years, | 0:42:59 | 0:43:03 | |
but to ensure scientific success, they also had to forecast | 0:43:03 | 0:43:07 | |
the weather on a planet three billion miles away from Earth. | 0:43:07 | 0:43:12 | |
We had to forecast where to point the cameras, | 0:43:12 | 0:43:17 | |
two weeks in advance, | 0:43:17 | 0:43:19 | |
where those interesting features were going to be. | 0:43:19 | 0:43:22 | |
And we said, "Well, they're moving around. | 0:43:22 | 0:43:25 | |
"There are storms in the atmosphere of Neptune." | 0:43:25 | 0:43:27 | |
And this was August of 1989, | 0:43:27 | 0:43:29 | |
and there was a big hurricane off the coast of Florida. | 0:43:29 | 0:43:33 | |
And weather forecasters here were saying, | 0:43:33 | 0:43:36 | |
"Well, 12 hours from now, we think it's going to veer right | 0:43:36 | 0:43:39 | |
"or we think it's going to go left, but we're not sure." | 0:43:39 | 0:43:42 | |
It may be starting to turn a little bit more towards | 0:43:42 | 0:43:44 | |
the northwest or west-northwest... | 0:43:44 | 0:43:45 | |
And, meanwhile, we were confidently issuing weather forecasts | 0:43:45 | 0:43:49 | |
for Neptune two weeks in advance and telling the engineers, | 0:43:49 | 0:43:53 | |
"OK, two weeks from now, | 0:43:53 | 0:43:54 | |
"point your camera there and there will be a storm there." | 0:43:54 | 0:43:57 | |
And we were right. It was glorious! | 0:43:57 | 0:44:00 | |
The fly-by was approaching. | 0:44:01 | 0:44:04 | |
Would the software rewrites and running repairs hold together | 0:44:04 | 0:44:08 | |
to give humanity its only close encounter with Neptune? | 0:44:08 | 0:44:12 | |
There was nothing more to do but wait and hope. | 0:44:12 | 0:44:17 | |
After 12 years of flight, and decades of anticipation, | 0:44:21 | 0:44:25 | |
the giant blue planet began to loom in Voyager 2's lenses. | 0:44:25 | 0:44:29 | |
On the 25th August 1989, the spacecraft passed | 0:44:47 | 0:44:51 | |
within 3,000 miles of Neptune's north pole. | 0:44:51 | 0:44:54 | |
The craft had survived the three billion mile journey | 0:45:00 | 0:45:03 | |
to the edge of the solar system. | 0:45:03 | 0:45:05 | |
APPLAUSE | 0:45:05 | 0:45:07 | |
The final encounter I was able to witness, | 0:45:07 | 0:45:11 | |
here at JPL with my youngest son, | 0:45:11 | 0:45:15 | |
and we watched with fascination as the pictures of Neptune unfolded. | 0:45:15 | 0:45:19 | |
Suddenly things that no-one had imagined were there. | 0:45:19 | 0:45:24 | |
Here was a planet that was vibrant with life. | 0:45:24 | 0:45:27 | |
It had its own great spot, a dark spot in this case, | 0:45:27 | 0:45:31 | |
white clouds floating in its atmosphere, | 0:45:31 | 0:45:33 | |
and these things unfolded before our very eyes. | 0:45:33 | 0:45:36 | |
What a wonderful surprise. | 0:45:36 | 0:45:38 | |
Neptune, for me, was a great surprise. | 0:45:38 | 0:45:41 | |
There was something strange and eerie about Neptune, | 0:45:46 | 0:45:50 | |
because here, the last planet, the sentinel at the outer edge | 0:45:50 | 0:45:55 | |
of our solar system, looks like Earth, | 0:45:55 | 0:45:58 | |
with its beautiful deep blue colour | 0:45:58 | 0:46:01 | |
and its white clouds floating in the atmosphere. | 0:46:01 | 0:46:04 | |
We were back with a really exciting planet again at Neptune. | 0:46:10 | 0:46:13 | |
There were fast-moving clouds, | 0:46:13 | 0:46:15 | |
clouds that moved in different directions, | 0:46:15 | 0:46:18 | |
some of them almost at sonic speeds. | 0:46:18 | 0:46:20 | |
The complexity of the planet's atmosphere | 0:46:20 | 0:46:22 | |
was far beyond our expectations. | 0:46:22 | 0:46:25 | |
The Grand Tour was almost over, | 0:46:31 | 0:46:34 | |
but Voyager 2 had one more surprise in store. | 0:46:34 | 0:46:38 | |
Neptune's moon, Triton. | 0:46:44 | 0:46:46 | |
This is too much... too much to believe. | 0:47:00 | 0:47:03 | |
-Look at the tyre tracks. -Yeah. | 0:47:08 | 0:47:11 | |
Tyre tracks. | 0:47:11 | 0:47:13 | |
Triton was a world unlike any we had seen before. | 0:47:15 | 0:47:19 | |
It was the coldest surface we had seen in the solar system, | 0:47:19 | 0:47:21 | |
40 degrees above absolute zero. | 0:47:21 | 0:47:24 | |
So cold that nitrogen, which forms most of the atmosphere on Earth, | 0:47:24 | 0:47:29 | |
is frozen, solid ice, | 0:47:29 | 0:47:31 | |
and the polar caps on Triton are frozen nitrogen, not frozen water. | 0:47:31 | 0:47:36 | |
Even so, we found geysers on the surface of Triton, | 0:47:36 | 0:47:41 | |
nitrogen geysers miles high. | 0:47:41 | 0:47:43 | |
So even at the very deepest part of our solar system, | 0:47:43 | 0:47:48 | |
there is geologic activity. | 0:47:48 | 0:47:49 | |
It is everywhere. | 0:47:49 | 0:47:50 | |
The solar system is alive, evolving, | 0:47:50 | 0:47:53 | |
and that's what makes it so exciting, | 0:47:53 | 0:47:55 | |
and makes it so much to learn. | 0:47:55 | 0:47:57 | |
Voyager 2 had survived to reach the extremes of the solar system. | 0:48:01 | 0:48:05 | |
It had revealed not just the planets themselves | 0:48:05 | 0:48:09 | |
but whole systems of rings and moons unlike anything we'd imagined. | 0:48:09 | 0:48:14 | |
Suzanne Dodd captured a final image from the flight. | 0:48:15 | 0:48:18 | |
One of the images I took and helped design | 0:48:19 | 0:48:22 | |
was the one where you have... | 0:48:22 | 0:48:23 | |
It's actually one taken when you're going away. | 0:48:23 | 0:48:26 | |
You have Neptune, the crescent of Neptune, | 0:48:26 | 0:48:30 | |
and then you have the crescent of Neptune's moon, Triton, | 0:48:30 | 0:48:32 | |
in the background, and you're taking that as the spacecraft is | 0:48:32 | 0:48:35 | |
travelling out of the solar system. | 0:48:35 | 0:48:38 | |
That's the last image that Voyager 2 is going to take, | 0:48:38 | 0:48:42 | |
and that's the last image that spacecraft is going to | 0:48:42 | 0:48:44 | |
remember of those planets. | 0:48:44 | 0:48:47 | |
MUSIC: Hoppipolla by Sigur Ros | 0:48:50 | 0:48:53 | |
Voyager 2 delivered its final images in 1989. | 0:48:57 | 0:49:02 | |
More data on the outer planets had been collected by | 0:49:04 | 0:49:07 | |
the two Voyager spacecraft than in the rest of human history. | 0:49:07 | 0:49:12 | |
But let's not forget Voyager 1, | 0:49:29 | 0:49:31 | |
heading out of the plane of the solar system. | 0:49:31 | 0:49:34 | |
Although it hadn't been able to have any more encounters with planets, | 0:49:34 | 0:49:38 | |
there was one last, special task its makers asked of it. | 0:49:38 | 0:49:43 | |
Because it was high above the solar system rather than in its plane, | 0:49:44 | 0:49:49 | |
Voyager 1 had a view of all the planets | 0:49:49 | 0:49:52 | |
that its twin could never have. | 0:49:52 | 0:49:54 | |
Carl Sagan and Carolyn Porco began discussing an idea. | 0:49:55 | 0:49:59 | |
Voyager was going to be in a location | 0:50:03 | 0:50:06 | |
that no other spacecraft had been before, equipped with, | 0:50:06 | 0:50:11 | |
you know, sophisticated instrumentation | 0:50:11 | 0:50:14 | |
so that it could turn around and take a picture | 0:50:14 | 0:50:17 | |
of all the planets in the solar system. | 0:50:17 | 0:50:21 | |
And I thought that this would be a riveting collection of images, | 0:50:21 | 0:50:24 | |
you know, a first. | 0:50:24 | 0:50:25 | |
And they said, "Well, there's really no scientific justification | 0:50:27 | 0:50:31 | |
"for this," and I couldn't argue with that, because there wasn't. | 0:50:31 | 0:50:35 | |
The planets were going to be just pinpoints, | 0:50:35 | 0:50:37 | |
they were going to be just pixels. | 0:50:37 | 0:50:39 | |
They couldn't see it. | 0:50:39 | 0:50:41 | |
On Valentine's Day 1990, 13 years after leaving Earth, | 0:50:45 | 0:50:51 | |
Voyager 1 was asked to turn its cameras back towards the planets. | 0:50:51 | 0:50:55 | |
Now 3.7 billion miles away, | 0:50:57 | 0:51:01 | |
by the time Voyager's pitifully weak signal reached | 0:51:01 | 0:51:04 | |
the dishes on Earth, | 0:51:04 | 0:51:06 | |
it was just a millionth of a billionth of a watt of power. | 0:51:06 | 0:51:10 | |
It was then boosted and sent on to Pasadena, | 0:51:10 | 0:51:14 | |
where the image was assembled, here in the Deep Space Control Room. | 0:51:14 | 0:51:18 | |
A unique family portrait, | 0:51:21 | 0:51:24 | |
the ultimate snapshot of our solar system. | 0:51:24 | 0:51:27 | |
And this is it! | 0:51:33 | 0:51:34 | |
There's actually only six planets visible, | 0:51:34 | 0:51:36 | |
because Mercury and Mars were obscured by the sun's glare. | 0:51:36 | 0:51:39 | |
But the picture that captured everybody's imagination | 0:51:39 | 0:51:42 | |
was that of Earth, | 0:51:42 | 0:51:43 | |
only a tenth of a pixel in size. | 0:51:43 | 0:51:46 | |
And here it is blown up. | 0:51:46 | 0:51:47 | |
Here is the mosaic... | 0:51:51 | 0:51:54 | |
For Carl Sagan, the symbolic value of the photograph was a gift. | 0:51:54 | 0:52:00 | |
He held a press conference to publicise it around the world. | 0:52:00 | 0:52:05 | |
The portrait of the planets has now been taken. | 0:52:05 | 0:52:09 | |
This looks more than a dot, | 0:52:09 | 0:52:13 | |
but it is in fact less than a pixel. | 0:52:13 | 0:52:16 | |
In this colour picture, you can see it is slightly blue, | 0:52:16 | 0:52:21 | |
and this is where we live, on a blue dot. | 0:52:21 | 0:52:26 | |
With this final historic image captured, | 0:52:28 | 0:52:30 | |
and nothing more to photograph, | 0:52:30 | 0:52:32 | |
Voyager 1's cameras were switched off to save power. | 0:52:32 | 0:52:36 | |
But that wasn't the end of the mission. | 0:52:43 | 0:52:46 | |
Over 35 years on, | 0:52:46 | 0:52:47 | |
as they hurtle away from us at over 10 miles a second, | 0:52:47 | 0:52:52 | |
their cutting-edge 1970s technology keeps on chugging. | 0:52:52 | 0:52:56 | |
And remarkably, | 0:53:00 | 0:53:01 | |
they continue to send back new information about the space | 0:53:01 | 0:53:05 | |
they're now travelling through, 11 billion miles from Earth. | 0:53:05 | 0:53:09 | |
Even travelling at the speed of light, | 0:53:13 | 0:53:15 | |
their messages take quite a while to get home. | 0:53:15 | 0:53:18 | |
The journey time now is about 15 hours one way | 0:53:20 | 0:53:23 | |
from Voyager 1 back to Earth, | 0:53:23 | 0:53:24 | |
so you send a signal up, | 0:53:24 | 0:53:27 | |
and the next day, you come back and you have some indication | 0:53:27 | 0:53:30 | |
that the spacecraft heard the signal and responded. | 0:53:30 | 0:53:33 | |
There are five instruments that are still operating on the spacecraft, | 0:53:35 | 0:53:40 | |
and we're starting to see the evidence now in the data | 0:53:40 | 0:53:43 | |
that we are crossing into interstellar space. | 0:53:43 | 0:53:45 | |
We're seeing things that would lead us to believe | 0:53:45 | 0:53:48 | |
that we are on that boundary. | 0:53:48 | 0:53:51 | |
Now, at the end of 2012, our planetary explorers are crossing | 0:53:51 | 0:53:55 | |
this boundary of the sun's influence. | 0:53:55 | 0:53:59 | |
They're travelling beyond the limits of our solar wind | 0:53:59 | 0:54:02 | |
and into the galaxy beyond. | 0:54:02 | 0:54:04 | |
It's the first time any object built by humans has achieved this. | 0:54:04 | 0:54:09 | |
A new chapter in human exploration is beginning. | 0:54:09 | 0:54:13 | |
We have enough power to get us to about ten more years, | 0:54:13 | 0:54:16 | |
maybe out to 2025, but we will, over the course of those years, | 0:54:16 | 0:54:20 | |
have to turn off things so that we continue to have enough power | 0:54:20 | 0:54:24 | |
to run the transmitter to send the data back to Earth. | 0:54:24 | 0:54:28 | |
The fact that Voyager's still alive | 0:54:34 | 0:54:36 | |
and there's still a signal from it | 0:54:36 | 0:54:39 | |
and it's about to leave the solar system, I think that's wonderful. | 0:54:39 | 0:54:44 | |
That it hasn't just given up or that we haven't given up on it. | 0:54:44 | 0:54:48 | |
It's a tribute to what Voyager means to us that we've kept it going. | 0:54:48 | 0:54:54 | |
Really, it's wonderful, as a scientist, to be still exploring, | 0:54:56 | 0:55:00 | |
still going somewhere no spacecraft has been before. | 0:55:00 | 0:55:03 | |
35 years on, this one mission has seen the team at JPL age, | 0:55:04 | 0:55:10 | |
events in their lives running parallel to | 0:55:10 | 0:55:13 | |
the Voyager's encounters. | 0:55:13 | 0:55:15 | |
When I started on the Voyager, my two daughters were young. | 0:55:15 | 0:55:19 | |
By the time they were in college, we already had passed Saturn | 0:55:19 | 0:55:23 | |
and were on our way to Uranus. | 0:55:23 | 0:55:25 | |
They got married, and the Voyager just kept going. | 0:55:25 | 0:55:27 | |
We had grandchildren, and Voyager just kept going, | 0:55:27 | 0:55:30 | |
and so now our grandchildren are aware | 0:55:30 | 0:55:31 | |
of what's happening to Voyager, just like our children were. | 0:55:31 | 0:55:35 | |
Long after all their power has gone, | 0:55:35 | 0:55:38 | |
the Voyagers will continue to rush away from us. | 0:55:38 | 0:55:42 | |
One and a half tonnes of 1970s engineering, | 0:55:42 | 0:55:45 | |
monuments to human endeavour and exploration, | 0:55:45 | 0:55:49 | |
heading out towards the stars. | 0:55:49 | 0:55:51 | |
I believe the next encounter with the closest star | 0:55:52 | 0:55:56 | |
is something like 40,000 years from now. | 0:55:56 | 0:55:59 | |
The two Voyager spacecraft are the furthest that we've ever sailed, | 0:56:06 | 0:56:11 | |
but for all their amazing science | 0:56:11 | 0:56:13 | |
and new worlds that they've found and data that they've collected, | 0:56:13 | 0:56:17 | |
the Voyager mission is still an incredibly symbolic mission. | 0:56:17 | 0:56:21 | |
Because those two golden discs are still fixed | 0:56:22 | 0:56:25 | |
to the sides of each spacecraft. | 0:56:25 | 0:56:28 | |
And in the benign, empty environment of deep space, | 0:56:28 | 0:56:32 | |
they will outlive the pyramids, they're likely to outlive us, | 0:56:32 | 0:56:36 | |
and perhaps even the Earth itself - the only record of our existence. | 0:56:36 | 0:56:41 | |
'Hello from the children of planet Earth.' | 0:56:43 | 0:56:46 | |
Yet, despite the ambition, | 0:56:46 | 0:56:49 | |
given the vastness of space, it's almost inconceivable | 0:56:49 | 0:56:53 | |
that these two tiny spacecraft will ever be intercepted by other beings. | 0:56:53 | 0:56:59 | |
It's a little bit like throwing a bottle into the cosmic ocean. | 0:56:59 | 0:57:05 | |
But Sagan was clever enough to realise this. | 0:57:05 | 0:57:08 | |
He knew it wasn't what the golden record said to | 0:57:09 | 0:57:12 | |
other civilisations that mattered - | 0:57:12 | 0:57:15 | |
more significant was what it said to our own. | 0:57:15 | 0:57:18 | |
You might think that it is a hopelessly quixotic project | 0:57:20 | 0:57:23 | |
to launch this message in a bottle into interstellar space | 0:57:23 | 0:57:29 | |
and expect anyone will find it, | 0:57:29 | 0:57:31 | |
but there are really two kinds of recipients of the message | 0:57:31 | 0:57:35 | |
on the Voyager records. | 0:57:35 | 0:57:37 | |
One is the extraterrestrial audience. | 0:57:37 | 0:57:42 | |
The other one is the audience down here down on Earth. | 0:57:42 | 0:57:44 | |
Here is a moment when we have to suddenly think, | 0:57:44 | 0:57:49 | |
"What is there about our culture | 0:57:49 | 0:57:51 | |
"that we would want others to know about, | 0:57:51 | 0:57:54 | |
"that we would be proud of?" | 0:57:54 | 0:57:56 | |
The record should represent the human species as an entirety. | 0:57:56 | 0:58:01 | |
The unity of the human species, seen down here, | 0:58:04 | 0:58:07 | |
is a fact that is essential for the human future. | 0:58:07 | 0:58:11 | |
MUSIC: Over The Rainbow by Israel Kamakawiwo'ole | 0:58:20 | 0:58:24 | |
# Oh, someday I'll wish upon a star | 0:58:24 | 0:58:28 | |
# Wake up where the clouds are far behind | 0:58:28 | 0:58:34 | |
# Me | 0:58:34 | 0:58:36 | |
# Where trouble melts like lemon drops | 0:58:36 | 0:58:39 | |
# High above the chimney top | 0:58:39 | 0:58:42 | |
# That's where you'll find me | 0:58:42 | 0:58:47 | |
# Oh, somewhere over the rainbow | 0:58:47 | 0:58:55 | |
# Way up high... # | 0:58:55 | 0:58:57 |