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Three, two, one, zero.
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In August 1977, two spacecraft called
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Voyager began an incredible journey.
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If they could survive the dangers
that lay across billions
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of miles of space, they would
reach worlds more distant
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and strange than anyone could
possibly have imagined.
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The gas giants.
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Voyager was heading towards
four vast planets,
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each thousands of times
bigger than the Earth.
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Jupiter with it's strange bands of cloud,
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and it's great red spot.
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A world crackling with radiation
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that can be heard from Earth.
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Beyond Jupiter was Saturn.
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How did this planet alone come to have it's
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spectacular set of rings?
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Stranger still was Uranus.
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It was known from how it's
moons orbited, that Uranus had
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been tipped over on it's back.
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But how had this happened?
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Neptune was barely visible,
even through the most
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powerful telescopes.
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What kinds of world's were these?
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And what could they reveal about
the solar system of which
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Earth is such a tiny part.
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Roger zero G and I feel fine.
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Capsule is turning around.
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Oh, that view is tremendous.
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In the early 1960's, sending a spacecraft
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all the way to the giants was unthinkable.
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Men had flown just a few
hundred miles up in orbit
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around the Earth.
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Unmanned probes ventured
further, but only to the nearest
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planets, Venus and Mars.
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Signal level has gone way down.
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Report continuing low signal levels.
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Even this was pushing the very limits
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of what was possible.
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In 1964, the first spacecraft,
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Mariner 4, flew by Mars.
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The spacecraft just barely made it there.
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Yes, it's there.
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And so the concept to go on to Jupiter
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which was almost half a billion miles away,
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Saturn, almost a billion,
Uranus, almost two and
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Neptune, almost 3 billion
miles away and all up
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12 years in journey,
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was not even something one
could very easily imagine.
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A solution came from a
most unlikely source.
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A young student at NASA's Jet
Propulsion Laboratory was
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asked to calculate trajectories
for a flight to Jupiter.
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I was a summer student working
on my degree at the time.
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So when I was given the job of
looking at the outer planets,
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I thought that was like
a make-work project.
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I was kind of being kept out
of the way while the really
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important business of getting
to Mars was underway.
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Flandro discovered something that made the
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dream of a flight to the giant
planets a real possibility.
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Obviously, the first thing
is to determine when the
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planets are going to be in positions
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where we could reach them.
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So I drew very careful maps
of where the planets would be
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and one of the most important
drawings was one in which I
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drew the positions of the
planets versus the date.
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And the thing that caught my
attention immediately was
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that the lines for Jupiter,
Saturn, Uranus and Neptune all
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crossed in about the
1975, 76 time period.
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In other words, those four
major planets were on the
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same side of the sun and in the
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same general position at the same time.
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So it gave me the idea immediately
that we could do all of
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those planets with one flight.
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Flandro's discovery meant it might now be
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possible to travel further
into our Solar System.
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Rocket power alone could
propel a spacecraft
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no further than Jupiter.
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But scientists knew that
if a probe approached
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a planet at the right angle,
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it would be caught by
the planet's momentum.
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Then pitched off in a new
direction at a greater speed.
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The trick you use here is
you fire your rocket with
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enough propulsion to get to Jupiter.
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Which is after all, a long ways away.
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It's five times the distance of the Sun.
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Go by Jupiter in just the
right way that you get a
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gravitational slingshot effect.
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That propels you to Saturn.
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Same trick, if Saturn is in the
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right place at the right time.
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Which can propel you to
Uranus if Uranus is in the
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right place at the right
time and on to Neptune.
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Same deal.
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That happens about every 175 years.
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And it happened in terms
of launch date in 1977.
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And in fact, former administrator
of NASA, Tom Paine,
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used to make the joke that
the last time this happened,
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Thomas Jefferson was
President, and he blew it.
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For NASA, this was too good
an opportunity to miss.
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They announced a mission to
the giants called Voyager.
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It marked a new era for
astronomers who had struggled to
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understand the hazy views they
could see from telescopes
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based on Earth.
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The man chosen to lead the
imaging team was Brad Smith.
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I had started looking at Jupiter seriously
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back in the late 50's.
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But we were frustrated by the
difficulty of making such
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observations from the ground.
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And so when the opportunity
came up to be involved with
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Voyager, as I realised
for the first time I was
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gonna have that opportunity
to see Jupiter up close.
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To see detail we could never could possibly
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see from the ground.
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The hopes of astronomers
now lay in the hands
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of the mission engineers
who faced what seemed an
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impossible task.
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The comment that I frequently
heard from those I was
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working with was "That mission
is never going to happen."
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It's just too complicated.
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We had to build a machine
that could fly for perhaps
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10 years without failing,
and that was really
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pushing the limits of what
we thought we could do
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with electronics at that time.
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We had to pass through the
asteroid belt on the way.
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How can we get this large
spacecraft through that very
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dangerous area beyond
Mars without a collision?
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And that seemed to be a very,
very, very challenging task.
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One of the big worries was data transfer.
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Even if you could do this
flight, could we get any useful
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data back to the Earth?
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So there a great deal of worry about that.
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The engineers had a decade to make the
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Voyager mission possible.
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Around the world, giant
antennae were built.
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The deep space network ready
to communicate with probes
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across billions of miles.
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But it still wasn't known if
a spacecraft could survive
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hazards like the asteroid belt,
the band of drifting rocks
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between Mars and Jupiter.
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Voyager would have only one
chance, so two less elaborate
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probes were sent ahead to test the route.
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Pioneer 10 and 11 were launched
to Jupiter and Saturn.
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Pioneer 10 and 11 were a
very important part of the
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strategy in exploring
the outer solar system.
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It was critical to have the
Pioneers lead the way telling
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us about the environment and
making some very important
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discoveries which would then
allow us with the Voyagers to
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come in safely behind.
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James van Allen was a
veteran of missions to
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Mars and Venus.
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Now he led a team of scientists on Pioneer.
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Piopneer 10 was the first
venture beyond Mars.
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First time we were going at
such enormous distances.
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First time we were about to
cross the asteroid belt which
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lies between the orbits
of Mars and Jupiter.
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So it was a very hazardous
and high risk mission.
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And we had a keen sense of it's
historic possibilities and
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emblazing a trail to the outer planets.
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Pioneer 10 successfully got
through the asteroid belt and
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it was still performing beautifully.
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And so we now knew that in
fact it was possible to get to
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the outer planets safely.
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Another key question which
Pioneer 10 had to address was
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"How intense was the radiation
environment around Jupiter?"
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Since the 50's, radio emissions had been
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detected coming from Jupiter
suggesting there might be
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intense radiation around the planet.
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The man whose task it was
to investigate this was
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James van Allen.
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He had discovered bands of
radiation around Earth with
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the very first American satellite.
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These were later named
the "Van Allen belts."
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We have encountered a very
high intensity of radiation,
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which is of the order of 1,000
times as intense as could be
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attributed to cosmic rays
as ordinarily understood.
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Van Allen predicted large radiation belts
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around Jupiter.
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But even he did not anticipate
what Pioneer found.
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As we went in, the radiation
intensity got greater and
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greater and greater and greater
and greater and greater.
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And there was a very strong
apprehension about the
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survival of the electronic
equipment in this spacecraft.
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But it went up to a maximum,
kept going up and up,
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and we did survive, and then
it started going down again,
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so we could breathe a sigh of relief
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that we had finally made it.
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The radiation belts surrounding Jupiter
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turned out to be 10,000 times
more intense than Earth's.
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And Pioneer also encountered
a vast magnetic field
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stretching seven million
miles out from the planet.
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One thing that Pioneer 10
discovered was that Jupiter's
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magnetic field is the largest
structure in the solar system.
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If you could see it from the
Earth, in the sky, it would
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appear to be as large as the sun.
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Even though it's five times further away.
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But of course, it's invisible
and this is very damaging
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to spacecraft and can damage electronics.
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The Voyager probes had to be hurriedly
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redesigned to survive the
intense magnetic field
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and radiation belts of Jupiter.
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Pioneer saved our lives.
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Had we flown into that
unknowingly, with a more
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sophisticated electronics
and the more sophisticated
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mechanisms that we had on Voyager,
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we would have died right on the spot.
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We were well into the design
of that spacecraft when the
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Pioneer results came in.
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And we had to do a lot of redesign.
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As the launch date grew near,
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final preparations were made for Voyager.
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For any curious extra-terrestrials
they might meet,
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the probes carried a disc showing
where they had come from,
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and a collection of images from Earth.
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This was a moment that I had
imagined and thought about
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00:13:32,748 --> 00:13:35,168
for years and there it was happening.
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00:13:35,169 --> 00:13:38,229
Here was our spacecraft on the
way to Jupiter and Saturn
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and Uranus and Neptune.
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A very marvelous feeling indeed.
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00:13:44,267 --> 00:13:48,434
This was the world were
Voyager was heading.
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00:13:49,810 --> 00:13:53,259
It was nearly four centuries
since Galileo had turned the
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first telescope on Jupiter and discovered
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00:13:55,978 --> 00:14:00,145
four points of light
moving around the planet.
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These were it's four moons.
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The first proof that not everything
in the Universe revolves
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around the Earth.
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00:14:09,629 --> 00:14:12,861
For Voyager's chief scientist,
the mission promised a new
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era of discovery.
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00:14:15,741 --> 00:14:18,524
I think we all felt that we were
in the tradition of Galileo
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who was the first to see
the moon's of Jupiter.
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00:14:21,348 --> 00:14:24,429
And the first to apply an instrument
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to increase our ability
to observe the universe.
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Voyager is just the latest tool
which we as a civilization
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had managed to devise and
of course, the tool was so
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powerful that we saw things
nobody had seen before,
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00:14:38,023 --> 00:14:41,190
and that nobody had imagined we'd see.
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The probe was still 50 million miles from
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Jupiter when it sent back the views
237
00:14:49,886 --> 00:14:52,386
everyone had been waiting for.
238
00:15:05,943 --> 00:15:08,416
We all approached Jupiter
with great expectation and
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00:15:08,417 --> 00:15:12,267
we all had grandiose theories
about what we were gonna see.
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00:15:12,268 --> 00:15:14,744
But of course, Jupiter fooled us all.
241
00:15:14,745 --> 00:15:18,667
There was some bizarre
behavior, little clouds moving
242
00:15:18,668 --> 00:15:21,344
along and being swept up in
the great red spot and them
243
00:15:21,345 --> 00:15:25,749
being, it would spit them out again.
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00:15:25,750 --> 00:15:29,203
Other clouds roll along next
to one another, coalesce into
245
00:15:29,204 --> 00:15:32,704
a single cloud and then break apart again.
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00:15:35,999 --> 00:15:38,558
Those kinds of details are not understood.
247
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Not even now, not 20 years later.
248
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That first encounter with Jupiter
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was a marvelous time for me,
250
00:15:52,393 --> 00:15:56,314
especially the approach
shots showing the planet
251
00:15:56,315 --> 00:15:59,304
revolving and watching the
great red spot revolving.
252
00:15:59,305 --> 00:16:01,874
Getting closer and closer until
finally we could see that
253
00:16:01,875 --> 00:16:05,755
indeed this was the top of a large storm.
254
00:16:05,756 --> 00:16:08,615
As a child, I'd studied that,
and wondered if that was a
255
00:16:08,616 --> 00:16:12,401
storm or was that an island
floating in an ocean.
256
00:16:12,402 --> 00:16:14,651
It was very difficult to know
and finally, the answers were
257
00:16:14,652 --> 00:16:17,579
there before our eyes.
258
00:16:22,449 --> 00:16:24,902
Voyager revealed an
atmosphere of hydrogen and
259
00:16:24,903 --> 00:16:28,848
helium gas with huge
clouds moving much faster
260
00:16:28,849 --> 00:16:31,599
than had been imagined.
261
00:16:32,507 --> 00:16:35,983
Jupiter's winds gusted at
hundreds of miles an hour, and
262
00:16:35,984 --> 00:16:40,890
the red spot alone was three
times the size of the Earth.
263
00:16:40,891 --> 00:16:45,391
It was the greatest storm
in the solar system.
264
00:16:45,392 --> 00:16:47,929
Voyager hinted at why this should be.
265
00:16:47,930 --> 00:16:50,969
It found that Jupiter pushes
out twice as much energy
266
00:16:50,970 --> 00:16:52,867
as it receives from the Sun.
267
00:16:52,868 --> 00:16:56,110
Suggesting that it's core must be hot.
268
00:16:56,111 --> 00:16:59,310
Scientists now believe that
at the heart of this massive
269
00:16:59,311 --> 00:17:01,576
planet, the gases are compressed
270
00:17:01,577 --> 00:17:05,679
until they become a metallic liquid.
271
00:17:05,680 --> 00:17:09,359
This hot churning core could
be the powerhouse that drives
272
00:17:09,360 --> 00:17:10,616
Jupiter's winds.
273
00:17:10,617 --> 00:17:14,457
And like a dynamo, creates
the enormous magnetic fields
274
00:17:14,458 --> 00:17:17,041
around the planet.
275
00:17:22,298 --> 00:17:26,465
Voyager then turned it's cameras
towards Jupiter's moons.
276
00:17:31,418 --> 00:17:33,064
At the time of the encounter,
277
00:17:33,065 --> 00:17:35,648
Bruce Murray was head of J.P.L.
278
00:17:36,809 --> 00:17:40,445
Just before the mission, the
interest was on the planet,
279
00:17:40,446 --> 00:17:42,365
on those bands, the things that you could
280
00:17:42,366 --> 00:17:44,711
see through a telescope.
281
00:17:44,712 --> 00:17:48,231
There was hardly any interest
at all in the satellites of
282
00:17:48,232 --> 00:17:51,369
the planets because they
were mostly little spots,
283
00:17:51,370 --> 00:17:54,153
some of them we couldn't
even see, or course.
284
00:17:54,154 --> 00:17:57,716
I had to lead a one man crusade
to even have them listed as
285
00:17:57,717 --> 00:18:01,619
targets for Voyager when it went there.
286
00:18:01,620 --> 00:18:04,233
Scientists had expected
the moons of Jupiter
287
00:18:04,234 --> 00:18:07,240
to be cold, dead and covered in craters,
288
00:18:07,241 --> 00:18:08,741
like our own moon.
289
00:18:12,040 --> 00:18:15,218
What they found was a mixture
of worlds as different and
290
00:18:15,219 --> 00:18:18,302
surprising as the planets themselves.
291
00:18:19,432 --> 00:18:22,674
Io, the closest of Jupiter's
large moons turned out to be
292
00:18:22,675 --> 00:18:26,535
more geologically active than Earth.
293
00:18:26,536 --> 00:18:30,449
Jupiter's enormous gravity
stretches and squeezes lo forcing
294
00:18:30,450 --> 00:18:34,556
it to heat up so it stays molten inside.
295
00:18:34,557 --> 00:18:37,481
We found that lo had eight
active volcanoes on it.
296
00:18:37,482 --> 00:18:39,889
The most volcanically active
body in the solar system, and
297
00:18:39,890 --> 00:18:42,054
it's just a small moon.
298
00:18:42,055 --> 00:18:45,457
And that was so unexpected.
299
00:18:45,458 --> 00:18:49,097
And it was such a shift in
our paradigm about what was
300
00:18:49,098 --> 00:18:51,877
going on in the outer solar
system, where it's very cold,
301
00:18:51,878 --> 00:18:54,576
and presumably we thought, very dead.
302
00:18:54,577 --> 00:18:58,218
So in that sense, it characterized
for us the sense of
303
00:18:58,219 --> 00:19:00,842
seeing things that we really
hadn't thought about and
304
00:19:00,843 --> 00:19:03,042
that was in fact very characteristic
305
00:19:03,043 --> 00:19:06,100
of the rest of the mission.
306
00:19:06,101 --> 00:19:08,500
As lo orbits close to Jupiter, it is
307
00:19:08,501 --> 00:19:12,668
constantly brushing against
the planet's magnetic field.
308
00:19:14,121 --> 00:19:17,867
The little moon builds up a
huge electrical charge, which
309
00:19:17,868 --> 00:19:21,312
discharges onto Jupiter in
a continuous flow of three
310
00:19:21,313 --> 00:19:25,480
million amps, causing storms
on the surface of the planet.
311
00:19:36,131 --> 00:19:38,630
The next moon Europa was very different,
312
00:19:38,631 --> 00:19:42,439
but no less surprising.
313
00:19:42,440 --> 00:19:44,430
It had a surface of water.
314
00:19:44,431 --> 00:19:48,014
Ice, frozen as hard as rock.
315
00:19:51,796 --> 00:19:55,245
Underneath this icy crust,
scientists believe there are
316
00:19:55,246 --> 00:19:58,246
oceans of warm water.
317
00:20:10,679 --> 00:20:12,652
Further out, the moon Ganymede
318
00:20:12,653 --> 00:20:15,986
was bigger than the planet Mercury.
319
00:20:30,507 --> 00:20:34,410
Ganymede's landscapes of rock
and ice reminded Voyager's
320
00:20:34,411 --> 00:20:38,004
geologist Laurence Soderblom of Earth.
321
00:20:38,005 --> 00:20:41,247
Ganymede turned out to be really exciting.
322
00:20:41,248 --> 00:20:46,515
We found a broken surface,
complex patterns.
323
00:20:46,516 --> 00:20:50,457
It's kind of a cross between
ice flows in the Arctic
324
00:20:50,458 --> 00:20:52,714
and continental drift on the Earth.
325
00:20:52,715 --> 00:20:56,584
And so it's icy crust has been
sheared, twisted, broken.
326
00:20:56,585 --> 00:20:59,754
Something we didn't expect.
327
00:21:01,835 --> 00:21:06,313
The last major moon, Callisto,
was different again.
328
00:21:06,314 --> 00:21:10,590
Like our own moon, it was
covered with craters.
329
00:21:10,591 --> 00:21:13,540
Evidence of a violent past when meteorites
330
00:21:13,541 --> 00:21:17,291
crashed onto it's cold, icy surface.
331
00:21:22,972 --> 00:21:26,491
What Voyager discovered at
Jupiter's moons transformed the
332
00:21:26,492 --> 00:21:29,672
rest of the mission.
333
00:21:29,673 --> 00:21:31,873
The first thing that strikes one is
334
00:21:31,874 --> 00:21:33,818
"My lord, everything is different."
335
00:21:33,819 --> 00:21:37,242
So the diversity is overwhelming,
because this is a mission
336
00:21:37,243 --> 00:21:39,511
of discovery, this is Captain
Kirk, this is really,
337
00:21:39,512 --> 00:21:42,401
in the solar system,
seeing really new things.
338
00:21:42,402 --> 00:21:44,793
Io and Europa, there's a
twin, a pair there and
339
00:21:44,794 --> 00:21:46,214
there's a pair out at
Ganymede and Callisto.
340
00:21:46,215 --> 00:21:47,814
What about the relief from the cracks?
341
00:21:47,815 --> 00:21:49,584
Shouldn't the cracks anneal and flow also?
342
00:21:49,585 --> 00:21:51,320
In order for there to be enough heating.
343
00:21:51,321 --> 00:21:54,104
All of the scientists with
exception of me where
344
00:21:54,105 --> 00:21:56,440
atmospheric scientists and astronomers.
345
00:21:56,441 --> 00:22:00,582
And in fact, it wasn't until we
really recognized the exotic
346
00:22:00,583 --> 00:22:04,610
variety and diversity of the
satellites that geologists
347
00:22:04,611 --> 00:22:07,009
were really added to the Voyager team.
348
00:22:07,010 --> 00:22:08,514
Just rotate it out a little bit.
349
00:22:08,515 --> 00:22:10,183
And in fact, the satellites
in my view became
350
00:22:10,184 --> 00:22:14,351
the star of the whole Voyager experience.
351
00:22:22,677 --> 00:22:27,712
Jupiter's moons are a solar
system in miniature.
352
00:22:27,713 --> 00:22:31,018
As Jupiter formed, it's immense
gravity must have attracted
353
00:22:31,019 --> 00:22:35,593
a cloud of dust and gas from
which it's moons were born.
354
00:22:35,594 --> 00:22:39,094
Just as the planets formed around the Sun.
355
00:22:40,032 --> 00:22:43,198
Close to Jupiter are the
small, dense active worlds of
356
00:22:43,199 --> 00:22:45,699
Io and Europa.
357
00:22:46,836 --> 00:22:49,285
A mirror of the inner rocky planets,
358
00:22:49,286 --> 00:22:52,369
Venus, Earth and Mars.
359
00:22:53,844 --> 00:22:56,543
Further out, Ganymede and Callisto
360
00:22:56,544 --> 00:22:59,240
are larger, icy worlds.
361
00:22:59,241 --> 00:23:02,741
The giants of the Jupiter system.
362
00:23:10,259 --> 00:23:13,509
Voyager's next goal was Saturn.
363
00:23:17,160 --> 00:23:20,124
Early astronomers believed
Saturn was the last planet
364
00:23:20,125 --> 00:23:22,542
in the solar system.
365
00:23:23,527 --> 00:23:27,558
The first to observe the rings,
Giovanni Cassini, saw a flat
366
00:23:27,559 --> 00:23:30,809
disc with just one gap.
367
00:23:33,564 --> 00:23:36,655
Scientists hoped that Voyager
would reveal clues to the
368
00:23:36,656 --> 00:23:40,406
origin of these mysterious rings.
369
00:23:48,296 --> 00:23:51,096
And this time, after Voyager's
success in producing
370
00:23:51,097 --> 00:23:54,168
such powerful images of
Jupiter, the press and the
371
00:23:54,169 --> 00:23:56,227
public were queuing up for a glimpse of
372
00:23:56,228 --> 00:23:59,395
the first images of Saturn.
373
00:24:35,735 --> 00:24:37,270
We thought we knew it all.
374
00:24:37,271 --> 00:24:39,606
But once again, we were looking at a
375
00:24:39,607 --> 00:24:42,001
very, very complex situation.
376
00:24:42,002 --> 00:24:45,424
The rings were broken up into many rings.
377
00:24:45,425 --> 00:24:46,448
There were gaps in there.
378
00:24:46,449 --> 00:24:48,664
There were all sorts of dynamical phenomena
379
00:24:48,665 --> 00:24:50,915
that we didn't understand.
380
00:24:55,878 --> 00:24:59,940
So we very, very hurriedly
reprogrammed Voyager 2 to take a
381
00:24:59,941 --> 00:25:02,441
much closer look at the rings.
382
00:25:07,674 --> 00:25:11,855
When I began my work in about
1964, I had suggested that
383
00:25:11,856 --> 00:25:15,171
one thing we could do with
this particular mission was to
384
00:25:15,172 --> 00:25:17,380
fly between the planet and the rings.
385
00:25:17,381 --> 00:25:19,662
And very fortunately, we didn't do that.
386
00:25:19,663 --> 00:25:22,222
Because as we approached
Saturn, we saw that the
387
00:25:22,223 --> 00:25:24,697
region there that we would to
have to have flown through
388
00:25:24,698 --> 00:25:27,510
with the spacecraft was
filled with more rings.
389
00:25:27,511 --> 00:25:29,229
There was no question that
that spacecraft would not have
390
00:25:29,230 --> 00:25:33,313
survived trying to go through that gap.
391
00:25:36,142 --> 00:25:38,381
The imaging team could barely cope with all
392
00:25:38,382 --> 00:25:42,465
the new data coming in from Voyager 2.
393
00:25:43,661 --> 00:25:47,575
They saw delicate rings that
were inter-twined and rings
394
00:25:47,576 --> 00:25:51,743
that were held in place by
tiny moons called shepherds.
395
00:25:54,968 --> 00:25:57,899
There were strange features called spokes.
396
00:25:57,900 --> 00:26:02,067
Patches of dust particles
slightly raised above the rings.
397
00:26:03,669 --> 00:26:08,106
These caught the eye of one
young graduate student.
398
00:26:08,107 --> 00:26:10,325
I got involved in the study of
the spokes which were these
399
00:26:10,326 --> 00:26:14,847
ghostly features that
were seen to come and go.
400
00:26:14,848 --> 00:26:17,196
And it just came to my head to just kind of
401
00:26:17,197 --> 00:26:19,283
categorize the pictures.
402
00:26:19,284 --> 00:26:21,768
Into one pile, I put all of the
images that seemed to have
403
00:26:21,769 --> 00:26:23,101
a lot of spokes in them.
404
00:26:23,102 --> 00:26:26,269
Into another pile, I put those
images that seemed to have
405
00:26:26,270 --> 00:26:28,263
virtually no spokes at all.
406
00:26:28,264 --> 00:26:30,886
And I made an intermediate category.
407
00:26:30,887 --> 00:26:33,702
And of course, each image
was tagged with a time.
408
00:26:33,703 --> 00:26:36,071
And I basically just did an analysis
409
00:26:36,072 --> 00:26:38,259
on the computer of this.
410
00:26:38,260 --> 00:26:40,759
And found that the spokes actually
411
00:26:40,760 --> 00:26:43,392
weren't just sporadic, but in fact,
412
00:26:43,393 --> 00:26:47,476
they came and they went
with a certain period.
413
00:26:56,612 --> 00:26:58,873
Carolyn Porco discovered that the spokes
414
00:26:58,874 --> 00:27:01,492
followed Saturn's magnetic field as it
415
00:27:01,493 --> 00:27:04,410
rotated with the planet.
416
00:27:05,460 --> 00:27:08,834
I made my very first scientific discovery
417
00:27:08,835 --> 00:27:11,675
and just knowing that I had found something
418
00:27:11,676 --> 00:27:13,925
that nobody else on the face of the planet
419
00:27:13,926 --> 00:27:16,316
knew at that time was just
420
00:27:16,317 --> 00:27:19,900
such an exhilarating experience.
421
00:27:27,449 --> 00:27:31,066
But where did the rings come from?
422
00:27:31,067 --> 00:27:34,192
A possible answer was discovered
when Voyager encountered
423
00:27:34,193 --> 00:27:35,920
Saturn's moons.
424
00:27:35,921 --> 00:27:40,176
A collection of icy worlds
scarred by great impact craters
425
00:27:40,177 --> 00:27:43,898
made my meteorites long ago.
426
00:27:43,899 --> 00:27:45,686
The Saturnian system was more like
427
00:27:45,687 --> 00:27:47,491
what we had actually expected.
428
00:27:47,492 --> 00:27:51,581
Small, cold, icy moons which
are heavily cratered set of
429
00:27:51,582 --> 00:27:55,279
objects, but there were some
real surprises there as well.
430
00:27:55,280 --> 00:27:59,161
The innermost of the large
satellites is Mimus.
431
00:27:59,162 --> 00:28:01,465
We found large impacts.
432
00:28:01,466 --> 00:28:03,907
This crater called Herschel,
433
00:28:03,908 --> 00:28:06,483
is a fourth the size of the object.
434
00:28:06,484 --> 00:28:09,363
Nearly large enough to blast it apart.
435
00:28:09,364 --> 00:28:12,137
We find a similar impact crater on Tethys,
436
00:28:12,138 --> 00:28:13,438
the next moon out.
437
00:28:13,439 --> 00:28:16,061
And roughly a third the size of the object.
438
00:28:16,062 --> 00:28:18,309
So it's clear that in the
early history, they were
439
00:28:18,310 --> 00:28:21,551
being blasted by things that
were large enough to have
440
00:28:21,552 --> 00:28:23,802
torn them apart.
441
00:28:25,349 --> 00:28:29,071
If Mimas nearly got bashed
up to bits, then it's very
442
00:28:29,072 --> 00:28:31,609
likely that there were other
satellites that did get
443
00:28:31,610 --> 00:28:32,964
smashed up to bits.
444
00:28:32,965 --> 00:28:36,488
And the rings of Saturn probably came from
445
00:28:36,489 --> 00:28:39,973
a satellite that was
close in to the planet,
446
00:28:39,974 --> 00:28:41,722
got smashed up.
447
00:28:41,723 --> 00:28:44,664
The debris of the collisional shards got
448
00:28:44,665 --> 00:28:48,748
strewn out into a planetary ring system.
449
00:29:25,590 --> 00:29:29,089
As Voyager moved closer
to the planet itself,
450
00:29:29,090 --> 00:29:33,995
it found that Saturn was made
of the same gases as Jupiter.
451
00:29:33,996 --> 00:29:37,910
These two worlds of the great
gas giants of the solar system
452
00:29:37,911 --> 00:29:40,828
dwarfing all the other planets.
453
00:29:43,329 --> 00:29:45,921
Yet Saturn held mysteries of it's own.
454
00:29:45,922 --> 00:29:48,903
Saturn is smaller and colder than Jupiter.
455
00:29:48,904 --> 00:29:51,486
It generates less heat within and receives
456
00:29:51,487 --> 00:29:54,865
less energy from the Sun.
457
00:29:54,866 --> 00:29:58,506
Yet Voyager recorded even
faster winds on Saturn than on
458
00:29:58,507 --> 00:30:02,633
Jupiter, a thousand miles an hour.
459
00:30:02,634 --> 00:30:05,634
How this could happen was a mystery.
460
00:30:08,693 --> 00:30:10,430
And as voyager left Saturn,
461
00:30:10,431 --> 00:30:13,385
there was one final enigma.
462
00:30:13,386 --> 00:30:16,051
Saturn’s largest moon Titan, is the only
463
00:30:16,052 --> 00:30:20,446
moon in the solar system
with a thick atmosphere.
464
00:30:20,447 --> 00:30:22,637
Voyager's cameras were unable to penetrate
465
00:30:22,638 --> 00:30:26,805
this orange haze to discover
what’s laid beneath.
466
00:30:34,229 --> 00:30:38,366
I found myself alone, in
the voyager imaging area
467
00:30:38,367 --> 00:30:41,014
late in the evening, about
10 o’clock in the evening.
468
00:30:41,015 --> 00:30:44,022
And it was just me and
the television monitor.
469
00:30:44,023 --> 00:30:45,749
And this was the monitor
that showed us all the
470
00:30:45,750 --> 00:30:48,448
tremendous pictures that people
were gathered around and
471
00:30:48,449 --> 00:30:52,266
now it was just showing
the image of Saturn that
472
00:30:52,267 --> 00:30:56,010
Voyager 1 had as it
receded from the planet.
473
00:30:56,011 --> 00:30:59,935
And I was mesmerized by
this whole thing thinking
474
00:30:59,936 --> 00:31:02,359
about how human kind had
never seen Saturn from
475
00:31:02,360 --> 00:31:04,275
this perspective before,
because we have never
476
00:31:04,276 --> 00:31:06,600
been on the other side of Saturn before.
477
00:31:06,601 --> 00:31:09,366
And I was so moved by
478
00:31:09,367 --> 00:31:12,419
me and Saturn alone in this room that
479
00:31:12,420 --> 00:31:16,761
I was completely swept
away by the whole thing.
480
00:31:25,075 --> 00:31:28,222
Voyager’s next goal was
Uranus discovered just
481
00:31:28,223 --> 00:31:30,548
two hundred years before and still
482
00:31:30,549 --> 00:31:33,632
very much an unknown world.
483
00:31:36,039 --> 00:31:38,917
Would this strange planet,
tipped over on its back,
484
00:31:38,918 --> 00:31:43,085
resemble its great neighbours,
Jupiter and Saturn?
485
00:31:50,299 --> 00:31:54,031
Even travelling at over
50,000mph, it would take some
486
00:31:54,032 --> 00:31:58,199
five years for Voyager to reach Uranus.
487
00:32:02,757 --> 00:32:05,305
The engineers needed every
moment to prepare for there
488
00:32:05,306 --> 00:32:08,510
most difficult challenge yet.
489
00:32:08,511 --> 00:32:10,723
Voyager was planned to operate
at one billion miles at
490
00:32:10,724 --> 00:32:13,095
Saturn, it was now being asked
to operate at two billion
491
00:32:13,096 --> 00:32:16,332
miles at Uranus, where
the sun was very dim.
492
00:32:16,333 --> 00:32:17,520
We had to do several things.
493
00:32:17,521 --> 00:32:18,587
For instance, you have to have much
494
00:32:18,588 --> 00:32:20,404
longer exposures on the camera.
495
00:32:20,405 --> 00:32:22,789
And if you have too long an
exposure, the spacecraft's
496
00:32:22,790 --> 00:32:25,573
moving very rapidly, things become smeared.
497
00:32:25,574 --> 00:32:28,549
So we had to lean how to
program the spacecraft to
498
00:32:28,550 --> 00:32:31,749
turn it just the right rate so
it would compensate for the
499
00:32:31,750 --> 00:32:34,250
motion of the spacecraft.
500
00:32:38,586 --> 00:32:41,071
But when Voyager reached Uranus,
501
00:32:41,072 --> 00:32:44,739
it's cameras found little to photograph.
502
00:32:46,266 --> 00:32:50,560
We had been so spoilt by the
glamour and the color and the
503
00:32:50,561 --> 00:32:53,440
intricacies of what we saw in
the atmospheres of Jupiter
504
00:32:53,441 --> 00:32:57,002
and Saturn that Uranus was
a little bit of a letdown
505
00:32:57,003 --> 00:32:59,701
because it was so bland.
506
00:32:59,702 --> 00:33:03,433
There’s more atmosphere and
more haze above the clouds
507
00:33:03,434 --> 00:33:06,934
and so it’s hard to see features.
508
00:33:07,852 --> 00:33:10,264
Even at its closet to the planet,
509
00:33:10,265 --> 00:33:15,128
Voyager revealed little
detail about Uranus.
510
00:33:15,129 --> 00:33:17,229
Uranus is different than
Jupiter and Saturn in the
511
00:33:17,230 --> 00:33:20,407
sense that it has no internal heat source.
512
00:33:20,408 --> 00:33:22,690
Both Jupiter and Saturn
are radiating more energy
513
00:33:22,691 --> 00:33:24,791
than they receive from the
sun because there is still
514
00:33:24,792 --> 00:33:26,231
heat inside those planets.
515
00:33:26,232 --> 00:33:28,631
For some reason at Uranus that
heat source had been shut
516
00:33:28,632 --> 00:33:31,510
down and was not driving the atmosphere.
517
00:33:31,511 --> 00:33:34,428
So the atmosphere was much blander.
518
00:33:36,195 --> 00:33:40,129
Voyager had found a very
different kind of giant.
519
00:33:40,130 --> 00:33:42,806
A world many times smaller and colder than
520
00:33:42,807 --> 00:33:45,140
Jupiter and Saturn.
521
00:33:46,668 --> 00:33:48,982
It was shrouded in different gases.
522
00:33:48,983 --> 00:33:52,260
Mostly methane and ammonia,
under which scientists
523
00:33:52,261 --> 00:33:58,111
believed there might lie
oceans of water and ice.
524
00:33:58,112 --> 00:33:59,598
What exactly is that stuff?
525
00:33:59,599 --> 00:34:02,138
It's happening here.
526
00:34:02,139 --> 00:34:03,836
If Uranus had been something of a
527
00:34:03,837 --> 00:34:06,753
disappointment, the
imaging team found plenty
528
00:34:06,754 --> 00:34:10,171
of surprises in the planet’s moons.
529
00:34:17,797 --> 00:34:21,714
Most striking of all was
the tiny moon Miranda.
530
00:34:25,359 --> 00:34:28,089
Miranda looks like a three
dimensional jigsaw puzzle,
531
00:34:28,090 --> 00:34:31,214
which we see regions looking like
532
00:34:31,215 --> 00:34:33,273
giant complex race tracks.
533
00:34:33,274 --> 00:34:35,359
Almost as if it's put
together by a committee.
534
00:34:35,360 --> 00:34:38,168
There are pieces stuck on the
surface that look like they
535
00:34:38,169 --> 00:34:40,077
belong to different planets.
536
00:34:40,078 --> 00:34:42,957
And one idea was, that it was busted apart,
537
00:34:42,958 --> 00:34:45,840
and these core pieces stayed
538
00:34:45,841 --> 00:34:47,946
intact and then they were
539
00:34:47,947 --> 00:34:52,190
glued back together so you
get this hodge podge.
540
00:35:40,841 --> 00:35:42,963
Perhaps it was just such a collision
541
00:35:42,964 --> 00:35:46,814
on a much larger scale that
knocked Uranus itself over
542
00:35:46,815 --> 00:35:50,982
on its back in the earliest
days of the solar system.
543
00:36:01,083 --> 00:36:04,140
From Uranus onwards to Neptune,
544
00:36:04,141 --> 00:36:08,033
some 3 billion miles away from Earth.
545
00:36:08,034 --> 00:36:10,754
The probe would have to take a
precise trajectory over the
546
00:36:10,755 --> 00:36:14,199
north pole of the planet to
get the best view of Neptune
547
00:36:14,200 --> 00:36:18,095
and its large moon Triton.
548
00:36:18,096 --> 00:36:20,478
The challenge at Neptune was the
549
00:36:20,479 --> 00:36:22,013
most difficult one we had.
550
00:36:22,014 --> 00:36:26,224
We had to know within one second
when were going to fly over
551
00:36:26,225 --> 00:36:28,212
the north pole of Neptune.
552
00:36:28,213 --> 00:36:30,877
That was a major navigational challenge.
553
00:36:30,878 --> 00:36:34,162
We had never delivered that
kind of accuracy before and if
554
00:36:34,163 --> 00:36:36,797
we were right, it worked
and if we're wrong,
555
00:36:36,798 --> 00:36:39,282
we had no second chance.
556
00:36:39,283 --> 00:36:41,394
After 12 years in flight,
557
00:36:41,395 --> 00:36:44,562
Voyager arrived at Neptune.
558
00:36:45,800 --> 00:36:47,761
Brad Smith and his team feared after the
559
00:36:47,762 --> 00:36:50,633
bland face of Uranus, that
they'd see little when they
560
00:36:50,634 --> 00:36:53,681
got to the last giant.
561
00:36:53,682 --> 00:36:56,107
They need not have worried.
562
00:37:25,410 --> 00:37:28,042
The final encounter I was able to
563
00:37:28,043 --> 00:37:30,348
witness here at J.P.L.
564
00:37:30,349 --> 00:37:32,772
with my youngest son
565
00:37:32,773 --> 00:37:34,849
and we watched with fascination as the
566
00:37:34,850 --> 00:37:37,511
pictures of Neptune unfolded.
567
00:37:37,512 --> 00:37:41,675
Suddenly things that no one
had imagined were there.
568
00:37:41,676 --> 00:37:44,970
Here was a planet that
was vibrant with life.
569
00:37:44,971 --> 00:37:48,234
It had its own great spot,
the dark spot in this case.
570
00:37:48,235 --> 00:37:52,042
White clouds floating in its
atmosphere and these things
571
00:37:52,043 --> 00:37:54,108
unfolded before our very eyes,
572
00:37:54,109 --> 00:37:56,468
and what a wonderful surprise.
573
00:37:56,469 --> 00:38:00,052
Neptune for me was a great surprise.
574
00:38:04,554 --> 00:38:07,213
There was something strange
and eerie about Neptune
575
00:38:07,214 --> 00:38:10,096
because here, the last planet,
576
00:38:10,097 --> 00:38:12,638
the sentinel at the outer edge
577
00:38:12,639 --> 00:38:16,404
of our solar system looks
like Earth with it's
578
00:38:16,405 --> 00:38:18,845
beautiful deep blue color and its
579
00:38:18,846 --> 00:38:22,179
white clouds floating in the atmosphere.
580
00:38:27,796 --> 00:38:30,012
We were back with a really exciting planet
581
00:38:30,013 --> 00:38:31,644
again at Neptune.
582
00:38:31,645 --> 00:38:33,266
There were fast moving clouds.
583
00:38:33,267 --> 00:38:35,675
Clouds that moved in different directions.
584
00:38:35,676 --> 00:38:38,138
Some of them almost at sonic speeds.
585
00:38:38,139 --> 00:38:41,718
The complexity of the planet’s
atmosphere was far beyond
586
00:38:41,719 --> 00:38:44,552
our expectations.
587
00:38:48,691 --> 00:38:50,728
Neptune turned out to have the strongest
588
00:38:50,729 --> 00:38:53,021
winds of all.
589
00:38:53,022 --> 00:38:56,050
Here in the furthest
extremes of the solar system
590
00:38:56,051 --> 00:38:59,421
where the sun barely
penetrates the last giant
591
00:38:59,422 --> 00:39:03,268
defied all expectations.
592
00:39:03,269 --> 00:39:05,788
You might expect that the
further you got from the sun,
593
00:39:05,789 --> 00:39:07,974
where there is less energy
to drive the winds,
594
00:39:07,975 --> 00:39:11,066
the winds would be slower.
595
00:39:11,067 --> 00:39:14,532
Winds on Jupiter are already
hundreds of miles per hour.
596
00:39:14,533 --> 00:39:16,772
It turned out rather than
seeing slower winds,
597
00:39:16,773 --> 00:39:18,041
we found faster winds.
598
00:39:18,042 --> 00:39:21,428
We found winds over a thousand
miles per hour at Neptune.
599
00:39:21,429 --> 00:39:23,523
We now understand why that's the case.
600
00:39:23,524 --> 00:39:25,998
And that is if you have
enough energy, it creates a
601
00:39:25,999 --> 00:39:29,998
lot of turbulence and
that slows the wind down.
602
00:39:29,999 --> 00:39:33,422
At Neptune there was so
little energy that the wind
603
00:39:33,423 --> 00:39:37,590
basically got started and
would just go and go and go.
604
00:39:38,436 --> 00:39:40,973
Made of the same gases and ices, Neptune’s
605
00:39:40,974 --> 00:39:45,314
atmosphere was moving much
faster than Uranus’s.
606
00:39:45,315 --> 00:39:47,661
The last two giants were
very different from their
607
00:39:47,662 --> 00:39:50,775
more massive cousins.
608
00:39:50,776 --> 00:39:54,943
Uranus and Neptune are not
gas giants but ice giants.
609
00:40:03,393 --> 00:40:08,277
From Earth, nobody had seen a
full set of rings at Neptune.
610
00:40:08,278 --> 00:40:11,028
But some scientists believed
they had seen incomplete
611
00:40:11,029 --> 00:40:14,687
segments of a ring, which they called arcs.
612
00:40:14,688 --> 00:40:18,395
By the time we got to Neptune, I was
613
00:40:18,396 --> 00:40:21,320
leading the small group of individuals
614
00:40:21,321 --> 00:40:22,739
on the imaging team who were
615
00:40:22,740 --> 00:40:26,387
responsible for the rings
and the ring arcs.
616
00:40:26,388 --> 00:40:28,926
In fact, there was some people
on the Voyager imaging team
617
00:40:28,927 --> 00:40:31,750
who just completely doubted the
existence of these things.
618
00:40:31,751 --> 00:40:33,298
They thought we were crazy.
619
00:40:33,299 --> 00:40:37,228
They thought we were wasting
precious spacecraft resources.
620
00:40:37,229 --> 00:40:41,021
And so it was very gratifying
to finally see that one image
621
00:40:41,022 --> 00:40:44,818
come down were we captured,
finally caught them in the act,
622
00:40:44,819 --> 00:40:46,535
the Neptune ring arcs.
623
00:40:46,536 --> 00:40:50,286
So it was a tremendous achievement.
624
00:40:51,421 --> 00:40:56,225
Neptune is indeed surrounded by ring arcs.
625
00:40:56,226 --> 00:40:59,878
How they got there and why
the ring is incomplete
626
00:40:59,879 --> 00:41:02,379
is not yet known.
627
00:41:18,022 --> 00:41:21,605
The impossible mission was almost over.
628
00:41:22,523 --> 00:41:26,690
Neptune’s moon Triton was
the final encounter.
629
00:41:35,226 --> 00:41:38,531
Triton is a large moon, it's
about the same size as the
630
00:41:38,532 --> 00:41:40,312
planet Pluto actually.
631
00:41:40,313 --> 00:41:42,126
So if it were out in orbit around the sun,
632
00:41:42,127 --> 00:41:43,307
we would call it a planet.
633
00:41:43,308 --> 00:41:45,304
But it's in orbit around Neptune.
634
00:41:45,305 --> 00:41:48,590
But unlike all the other
satellites which orbit in the
635
00:41:48,591 --> 00:41:52,589
same direction as the planet
rotates, Triton is in
636
00:41:52,590 --> 00:41:53,784
retrograde orbit.
637
00:41:53,785 --> 00:41:56,930
It's going around Neptune
backwards, which told us it was
638
00:41:56,931 --> 00:42:00,066
not likely formed around Neptune,
639
00:42:00,067 --> 00:42:03,234
but had been captured by Neptune.
640
00:42:06,328 --> 00:42:09,071
Triton is a moon that
might've been a planet,
641
00:42:09,072 --> 00:42:11,191
but it strayed too close to Neptune
642
00:42:11,192 --> 00:42:14,442
and was caught by it's gravity.
643
00:42:20,351 --> 00:42:23,193
Triton turned out to be
one of the strangest
644
00:42:23,194 --> 00:42:25,861
worlds encountered.
645
00:42:34,596 --> 00:42:38,571
This is too much, this is much too much.
646
00:42:38,572 --> 00:42:42,739
Oh god, look at the tire tracks.
647
00:42:44,469 --> 00:42:47,628
Right, there you go.
648
00:42:47,629 --> 00:42:50,689
Triton was a world unlike
any we had seen before.
649
00:42:50,690 --> 00:42:53,463
It was the coldest surface
we'd seen in the solar system,
650
00:42:53,464 --> 00:42:55,535
40 degrees above absolute zero.
651
00:42:55,536 --> 00:42:59,067
So cold that nitrogen, which
forms most of the atmosphere
652
00:42:59,068 --> 00:43:02,523
on Earth, is frozen solid ice.
653
00:43:02,524 --> 00:43:06,182
And the polar capsules on
Triton are frozen nitrogen,
654
00:43:06,183 --> 00:43:08,235
not frozen water.
655
00:43:08,236 --> 00:43:13,285
Even so, we found geysers
on the surface of Triton.
656
00:43:13,286 --> 00:43:15,664
Nitrogen geysers miles high.
657
00:43:15,665 --> 00:43:18,965
So even at the very deepest
part of our solar system,
658
00:43:18,966 --> 00:43:21,359
there is geologic activity.
659
00:43:21,360 --> 00:43:25,513
It is everywhere, the solar
system is alive, evolving
660
00:43:25,514 --> 00:43:28,143
and that’s what makes it
so exciting and makes it,
661
00:43:28,144 --> 00:43:30,394
so much to learn.
662
00:43:34,918 --> 00:43:37,060
Voyager had survived to reach the extremes
663
00:43:37,061 --> 00:43:39,246
of the solar system.
664
00:43:39,247 --> 00:43:43,057
And reveal not just the giants
themselves, but whole systems
665
00:43:43,058 --> 00:43:47,225
of rings and moons unlike
anything imagined.
666
00:43:49,444 --> 00:43:52,003
As the planets moved out
of there alignment,
667
00:43:52,004 --> 00:43:56,920
Uranus and Neptune once again
drifted out of our reach.
668
00:43:56,921 --> 00:44:01,088
It's unlikely that they'll be
visited again in our lifetime.
669
00:44:08,845 --> 00:44:13,772
But Voyager was not the last
mission to the gas giants.
670
00:44:13,773 --> 00:44:17,456
In 1994, a probe named Galileo returned to
671
00:44:17,457 --> 00:44:20,602
Jupiter and its moons.
672
00:44:20,603 --> 00:44:23,695
It found that lo's surface
had been covered by fresh
673
00:44:23,696 --> 00:44:27,029
eruptions of sulphurous lava.
674
00:44:28,197 --> 00:44:31,780
Europa which had looked so
smooth, turned out to be covered
675
00:44:31,781 --> 00:44:35,031
in great ridges and chasms.
676
00:44:41,434 --> 00:44:45,601
Fresh detail was revealed in
Ganymede's alien landscapes.
677
00:44:50,095 --> 00:44:52,504
And there was more
destruction than had been
678
00:44:52,505 --> 00:44:55,088
imagined on Callisto.
679
00:45:07,831 --> 00:45:11,456
In October 1997, a mission called Cassini
680
00:45:11,457 --> 00:45:13,957
set off for Saturn.
681
00:45:18,176 --> 00:45:22,112
It will spend four years sending
back high resolution images
682
00:45:22,113 --> 00:45:26,280
of the great planet, it's rings
and it's many satellites.
683
00:45:30,926 --> 00:45:34,843
Head of the imaging team is Carolyn Porco.
684
00:45:36,352 --> 00:45:38,796
We are interested, for
scientific purposes in taking
685
00:45:38,797 --> 00:45:41,611
images of Titan and all the satellites too.
686
00:45:41,612 --> 00:45:45,110
So how many images do you think
you'll need in that block?
687
00:45:45,111 --> 00:45:47,073
Four is what we nominally talk about.
688
00:45:47,074 --> 00:45:48,012
Four images?
689
00:45:48,012 --> 00:45:48,845
Mm, hm.
690
00:45:48,845 --> 00:45:49,678
In 30 minutes.
691
00:45:49,678 --> 00:45:50,511
Mm, hm.
692
00:45:50,512 --> 00:45:51,734
OK.
693
00:45:51,735 --> 00:45:55,509
We have designed the camera
system specifically,
694
00:45:55,510 --> 00:45:57,301
among many other things.
695
00:45:57,302 --> 00:45:59,684
We’ve designed it see down
to the surface of Titan,
696
00:45:59,685 --> 00:46:01,225
which or course is something we weren't
697
00:46:01,226 --> 00:46:03,081
able to do on Voyager.
698
00:46:03,082 --> 00:46:05,328
And we'll be able to see things
699
00:46:05,329 --> 00:46:08,691
that are on the scale of office blocks.
700
00:46:08,692 --> 00:46:11,368
We'll be collecting data
from Cassini at least for
701
00:46:11,369 --> 00:46:12,509
a period of four years.
702
00:46:12,510 --> 00:46:15,420
So we’ll have a chance to monitor changes,
703
00:46:15,421 --> 00:46:18,663
and you know, it'll be a new era.
704
00:46:18,664 --> 00:46:22,820
But, it will never have the same feeling
705
00:46:22,821 --> 00:46:25,587
or even, even significance,
706
00:46:25,588 --> 00:46:27,979
historical significance
as Voyager had because
707
00:46:27,980 --> 00:46:29,821
that experience can never be duplicated.
708
00:46:31,399 --> 00:46:33,916
The next awards are the exceptional
709
00:46:33,917 --> 00:46:36,582
scientific achievement medal.
710
00:46:36,583 --> 00:46:39,462
The first award goes to Gary Flandro.
711
00:46:39,463 --> 00:46:42,171
For seminal contributions to
the design and engineering
712
00:46:42,172 --> 00:46:45,104
of missions, including the
grand tour of opportunity
713
00:46:45,105 --> 00:46:48,411
for the epic Voyager explorations.
714
00:46:51,430 --> 00:46:53,370
The views that were achieved
there at each of those
715
00:46:53,371 --> 00:46:56,175
outer planets far exceeded
any expectations,
716
00:46:56,176 --> 00:47:00,878
but it was a ghostly feeling
of having already being there.
717
00:47:00,879 --> 00:47:05,650
Myself flying that mission
in my mind in the 1960’s.
718
00:47:05,651 --> 00:47:07,177
Work all started right up in that office.
719
00:47:07,178 --> 00:47:08,318
Is that right?
720
00:47:08,319 --> 00:47:09,152
That’s where I was.
721
00:47:09,153 --> 00:47:10,590
Building 180’s where you worked?
722
00:47:10,591 --> 00:47:13,101
Sat out and looking out that
window, through those trees,
723
00:47:13,102 --> 00:47:15,175
and up towards the sun and I said
724
00:47:15,176 --> 00:47:19,343
"We could do this, four
planets in one flight."
725
00:47:20,648 --> 00:47:23,174
With the planets behind it, Voyager carried
726
00:47:23,175 --> 00:47:27,270
on to search for the very
edge of the solar system.
727
00:47:27,271 --> 00:47:29,531
Where the sun’s influence runs out,
728
00:47:29,532 --> 00:47:33,032
and interstellar space begins.
729
00:47:40,071 --> 00:47:41,829
The Voyager mission is not over.
730
00:47:41,830 --> 00:47:44,864
We hope we can continue
listening to it for at least
731
00:47:44,865 --> 00:47:47,196
another 20 years before we finally
732
00:47:47,197 --> 00:47:50,334
lose power on the spacecraft.
733
00:47:50,335 --> 00:47:53,629
In 2015, Voyager 1 will be 130 times as far
734
00:47:53,630 --> 00:47:54,596
from the sun as the Earth.
735
00:47:54,597 --> 00:47:58,716
About 12 billion miles from
the Earth and perhaps,
736
00:47:58,717 --> 00:48:00,850
in interstellar space for the first time.
737
00:48:00,851 --> 00:48:04,370
So we listen to the two Voyager
spacecraft everyday looking
738
00:48:04,371 --> 00:48:07,602
for some signal that we're getting close
739
00:48:07,603 --> 00:48:10,103
to interstellar space.
740
00:48:11,506 --> 00:48:13,905
The greatest Voyager in history
741
00:48:13,906 --> 00:48:16,656
is still travelling.
60491
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