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Jupiter Is Not What You Think _ What Lies Beneath Its Clouds_ · Boring Science

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  Speaker 1: Hello, and welcome to Boring Science to Sleep, a quiet
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  Speaker 1: place where science becomes slow, soft, and easy to drift through. Tonight,
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  Speaker 1: you're going to gently journey beneath the clouds of Jupiter,
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  Speaker 1: toward a world that is far stranger than it first appears.
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  Speaker 1: You are safe, there's nothing to do, nothing to remember,
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  Speaker 1: just listen and drift. Dim the lights, settle in, and
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  Speaker 1: let yourself become very still. Far away, Jupiter is already
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  Speaker 1: turning in the darkness, enormous, silent, and wrapped in clouds.
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  Speaker 1: And as you slowly drift closer, you may begin to
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  Speaker 1: notice that the Jupiter you thought you knew is only
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  Speaker 1: the very beginning. You can imagine yourself drifting through a
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  Speaker 1: very quiet darkness. There is no ground beneath you, no
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  Speaker 1: ceiling above you, nothing pressing against your shoulders, nothing asking
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  Speaker 1: you to move. just the soft darkness of space, and
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  Speaker 1: far away, a pale point of light becoming slowly larger.
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  Speaker 1: At first, Jupiter is only a distant presence, a bright
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  Speaker 1: shape surrounded by blackness, and as you drift closer, the
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  Speaker 1: little point gradually becomes a world. The bands begin to
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  Speaker 1: appear first, pale stripes moving gently across the enormous sphere,
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  Speaker 1: some brighter, some darker, some almost cream-coloured, all of them
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  Speaker 1: wrapped around the planet in broad, slow-moving patterns. You can
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  Speaker 1: see storms turning inside those bands, enormous storms that have
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  Speaker 1: no familiar ground beneath them, no mountain range, no ocean shore,
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  Speaker 1: no solid landscape to tell them where to stop. And
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  Speaker 1: somewhere among all of this, you can see the Great
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  Speaker 1: Red Spot, that enormous reddish storm that has become one
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  Speaker 1: of the most recognisable features in the entire solar system.
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  Speaker 1: From here, Jupiter looks almost peaceful. It turns quietly in
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  Speaker 1: the darkness. The clouds move. The storms move. Light from
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  Speaker 1: the distant sun touches the upper atmosphere. And nothing about
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  Speaker 1: the scene tells you how strange Jupiter becomes when you
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  Speaker 1: travel downward. Because the first thing you might imagine when
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  Speaker 1: you look at Jupiter is that it is simply a
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  Speaker 1: giant ball of gas. And that is understandable. Jupiter is
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  Speaker 1: called a gas giant. Its outer atmosphere is made mostly
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  Speaker 1: of hydrogen and helium, two of the lightest elements in nature,
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  Speaker 1: and when you look at the planet through a telescope,
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  Speaker 1: what you see really is a vast atmosphere of clouds
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  Speaker 1: and gases. But if you could somehow begin to descend
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  Speaker 1: through those clouds, you would slowly discover that the word
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  Speaker 1: gas becomes less and less useful. The deeper you go,
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  Speaker 1: the more tightly the material around you is pressed together.
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  Speaker 1: There is no sudden doorway, no clear line where one
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  Speaker 1: kind of Jupiter ends and another begins. Instead, everything changes gradually.
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  Speaker 1: The atmosphere becomes denser. The temperature rises. The pressure increases.
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  Speaker 1: And pressure, here, is not something mysterious. You can imagine
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  Speaker 1: it simply as the enormous weight of everything above you.
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  Speaker 1: Far above, there are layers of atmosphere. Below those, there
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  Speaker 1: are more layers. and below those, still more. Jupiter contains
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  Speaker 1: so much material that its own gravity quietly pulls that
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  Speaker 1: material inward, pressing the planet together from every direction, so
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  Speaker 1: as you drift downward, the feeling of space around you
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  Speaker 1: would slowly change. The airy world above would become a
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  Speaker 1: denser world, the particles would be closer together, the temperature
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  Speaker 1: would rise, and eventually, the hydrogen that once behaved like
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  Speaker 1: an ordinary gas would would no longer behave like the
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  Speaker 1: gas you know here on Earth. This is one of
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  Speaker 1: the quiet surprises of Jupiter. The planet does not have
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  Speaker 1: to become a completely different world all at once. It
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  Speaker 1: simply becomes different little by little. And perhaps that is
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  Speaker 1: why Jupiter is so easy to misunderstand. You see the clouds,
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  Speaker 1: but the clouds are only the outermost part of an
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  Speaker 1: enormous interior. You see the storms, but the storms are
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  Speaker 1: connected to a much deeper atmosphere. You see a planet
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  Speaker 1: that looks soft and gaseous from millions of kilometres away,
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  Speaker 1: but much of what lies below is dense fluid, compressed
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  Speaker 1: by the immense weight of Jupiter itself. And Jupiter is very,
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  Speaker 1: very large. Large enough that imagining its size using Earth
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  Speaker 1: alone can become difficult. By mass, Jupiter is heavier than
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  Speaker 1: all the other planets in our solar system combined, and
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  Speaker 1: by volume, roughly a thousand Earths could fit inside it.
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  Speaker 1: A thousand Earths. You can let that number drift through
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  Speaker 1: your mind without trying to calculate it. Imagine one small
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  Speaker 1: Earth as something you could hold gently between your fingers.
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  Speaker 1: Perhaps a grape. Now imagine Jupiter as something closer to
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  Speaker 1: a basketball. The comparison is not perfect, of course, but
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  Speaker 1: it gives your mind a soft place to rest. One
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  Speaker 1: world is familiar, the other is immense. And this immense
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  Speaker 1: size matters because gravity grows with the amount of matter
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  Speaker 1: gathered together. Jupiter's great mass gives it a powerful gravitational pull,
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  Speaker 1: and that pull reaches throughout the planet. It is the
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  Speaker 1: quiet tendency of everything to move inward. Dust. Gas. Cloud particles. Water. Hydrogen.
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  Speaker 1: Rocky material. All of it feels the influence of Jupiter's gravity,
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  Speaker 1: and as you descend … the enormous amount of material
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  Speaker 1: above you becomes increasingly important. You are moving deeper into
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  Speaker 1: a world where the planet itself is pressing inward. The
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  Speaker 1: deeper you go, the more the familiar idea of an
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  Speaker 1: atmosphere begins to soften. There is no simple surface waiting below,
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  Speaker 1: no boundary saying, here the clouds end, and here the
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  Speaker 1: planet begins. The clouds simply become thicker, the material becomes denser,
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  Speaker 1: the pressure becomes greater, the temperature becomes warmer, and the
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  Speaker 1: distinction between atmosphere and interior slowly fades. You might imagine
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  Speaker 1: yourself continuing downward through a world with no floor. Above you,
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  Speaker 1: the bright clouds are becoming distant. Below you, there is
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  Speaker 1: only more Jupiter, more hydrogen, more pressure, more warmth, more darkness,
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  Speaker 1: and for a moment you can simply rest there, You
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  Speaker 1: do not need to picture every layer. You do not
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  Speaker 1: need to remember every number. Just imagine that enormous planet
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  Speaker 1: turning quietly beneath the distant sun, while somewhere inside it,
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  Speaker 1: matter is slowly changing under the weight of the world above.
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  Speaker 1: Long before we could imagine travelling into such a place,
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  Speaker 1: human beings could only look at Jupiter from a distance. Then,
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  Speaker 1: little by little, spacecraft began to approach. They gave us
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  Speaker 1: clearer images. They showed us moving clouds. They showed us
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  Speaker 1: storms and moons and shadows. But photographs could only reveal
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  Speaker 1: the outside. The deeper mystery remained hidden, and eventually something
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  Speaker 1: remarkable happened. A comet came close to Jupiter, and Jupiter's
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  Speaker 1: enormous gravity pulled it apart. For a brief moment, the
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  Speaker 1: planet would become a kind of natural experiment, disturbing its
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  Speaker 1: own clouds and and allowing material from deeper regions to
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  Speaker 1: be thrown upward into view. And that quiet accident in
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  Speaker 1: the darkness would give us one of the most remarkable
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  Speaker 1: glimpses of Jupiter ever observed. For now, though, you can
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  Speaker 1: remain here, still far above the clouds. Jupiter turns slowly
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  Speaker 1: beneath you. The bands drift past. The great red spot
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  Speaker 1: moves quietly through the darkness. And beneath all of it
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  Speaker 1: is a world you cannot yet see. A world where
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  Speaker 1: gas will become liquid, where hydrogen will eventually behave in
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  Speaker 1: a way that seems almost impossible, and where even the
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  Speaker 1: planet's deepest centre may not have the neat boundary you
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  Speaker 1: would expect. But there is no need to hurry toward it.
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  Speaker 1: For the moment, you can simply remain above the clouds,
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  Speaker 1: watching this enormous world turn, knowing that beneath the soft
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  Speaker 1: appearance of Jupiter, something much denser and stranger is waiting
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  Speaker 1: quietly below. For a little while, you can remain above Jupiter,
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  Speaker 1: watching the great planet turn beneath you. The clouds continue
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  Speaker 1: their slow movement, the pale bands slipping gently around the
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  Speaker 1: enormous sphere, while the darkness of space remains almost completely still.
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  Speaker 1: From this distance, Jupiter seems to reveal itself quite generously.
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  Speaker 1: You can see its shape, you can see its storms,
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  Speaker 1: you can see the Great Red Spot. you can watch
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  Speaker 1: sunlight resting softly across the upper clouds, and yet, almost
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  Speaker 1: everything that makes Jupiter truly unusual remains hidden. There is
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  Speaker 1: a great deal happening beneath that visible surface, but from
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  Speaker 1: far away, you cannot simply look down and see it.
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  Speaker 1: You need something to disturb the clouds, something large enough
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  Speaker 1: to make Jupiter briefly reveal what normally remains concealed. And
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  Speaker 1: in the summer of 1994, something like that happened. A
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  Speaker 1: comet called Shoemaker-Levy 9 had been travelling through the solar system,
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  Speaker 1: a small body made from ancient material left over from
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  Speaker 1: the formation of the planets. As it came close to Jupiter,
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  Speaker 1: the planet's enormous gravity began to take control of its journey.
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  Speaker 1: Jupiter is so massive that its gravitational pull can reach
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  Speaker 1: far across space. The comet was caught by that pull,
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  Speaker 1: and under the strain of its encounter with the giant planet,
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  Speaker 1: it broke apart. Instead of one quiet object moving through space,
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  Speaker 1: there were now many pieces following one another toward Jupiter.
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  Speaker 1: You can imagine them drifting in a long, uneven line
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  Speaker 1: through the darkness. Small pieces. Larger pieces. Fragments separated by distances,
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  Speaker 1: but all following the same broad path. And then they
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  Speaker 1: began to fall toward Jupiter. There was no solid ground
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  Speaker 1: waiting beneath them. There was only the enormous atmosphere of
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  Speaker 1: the giant planet. The fragments entered one after another, and
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  Speaker 1: each collision released an extraordinary amount of energy. Scientists observed
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  Speaker 1: 21 separate impacts over several days. For the first time,
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  Speaker 1: people could watch something enormous happen to Jupiter, almost as
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  Speaker 1: though the planet itself had opened a series of small windows.
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  Speaker 1: Each impact disturbed the upper atmosphere. Dark marks appeared across
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  Speaker 1: the clouds. Some of the explosions sent material thousands of
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  Speaker 1: kilometres upward, creating enormous plumes that rose above the surrounding
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  Speaker 1: atmosphere and remained visible for weeks and even months. You
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  Speaker 1: can let that image become very slow in your mind.
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  Speaker 1: A fragment disappears into the clouds. For a moment, nothing
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  Speaker 1: seems to happen. Then the atmosphere changes. A great plume rises.
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  Speaker 1: Material moves upward through the darkness. And far above the clouds,
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  Speaker 1: sunlight catches the disturbed material. Then the planet slowly settles again.
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  Speaker 1: The largest of these impacts released an amount of energy
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  Speaker 1: almost too large to picture comfortably. There is no need
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  Speaker 1: to imagine the exact comparison. It is enough to think
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  Speaker 1: of an event so powerful that Jupiter's own atmosphere was
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  Speaker 1: visibly disturbed across an enormous region. And this was happening
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  Speaker 1: on a world already enormous beyond ordinary scale. The strange
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  Speaker 1: beauty of the event was was that it happened at
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  Speaker 1: exactly the right time for human beings to watch. The
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  Speaker 1: Hubble Space Telescope observed the dark marks left behind in
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  Speaker 1: the clouds, and the Galileo spacecraft, already travelling toward Jupiter,
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  Speaker 1: was also in position to observe the impacts and the
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  Speaker 1: material they threw upward. Galileo had not been sent there
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  Speaker 1: specifically to watch a comet strike Jupiter, but its journey
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  Speaker 1: happened to overlap with this extraordinary event. and as Galileo
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  Speaker 1: approached the planet, it had an opportunity to pass through
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  Speaker 1: material that had been disturbed and thrown upward above the clouds.
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  Speaker 1: For a brief moment, Jupiter's hidden layers were no longer
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  Speaker 1: completely hidden. The planet had been shaken, its atmosphere had
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  Speaker 1: been disturbed, and some of the material that normally remained
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  Speaker 1: buried beneath the visible clouds had been brought closer to
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  Speaker 1: the light. It was almost as though you were looking
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  Speaker 1: at a deep ocean and after a gentle but powerful
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  Speaker 1: movement had stirred its lower layers. You still could not
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  Speaker 1: see the entire ocean. You still could not see its
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  Speaker 1: deepest regions. But for a moment, material from below had
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  Speaker 1: risen toward the surface. And Galileo found something especially interesting. Water.
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  Speaker 1: This might sound simple at first. Water is familiar. You
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  Speaker 1: know it as rain. You know it as snow and ice.
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  Speaker 1: You know it as something that fills oceans, rivers, clouds,
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  Speaker 1: and even a glass beside your bed. But on Jupiter,
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  Speaker 1: water was part of a much stranger story. The amount
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  Speaker 1: detected beneath the visible cloud layer was not what scientists
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  Speaker 1: had comfortably expected. The earlier understanding of Jupiter had been
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  Speaker 1: too simple. The planet was not merely a huge envelope
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  Speaker 1: of hydrogen and helium surrounding a small hidden centre. Its
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  Speaker 1: atmosphere and deeper regions contained more complexity. There was water,
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  Speaker 1: there were unusual cloud processes, there were materials moving downward
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  Speaker 1: and upward, and beneath everything, pressure and temperature were changing
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  Speaker 1: the very nature of matter. The surprising observations from Galileo
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  Speaker 1: helped create a new question. If water was present in
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  Speaker 1: unexpected amounts, what else had scientists misunderstood about the interior?
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  Speaker 1: And how far beneath the clouds did these changes continue?
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  Speaker 1: These were questions that could not be answered by simply
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  Speaker 1: taking another photograph. A photograph could show the clouds, but
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  Speaker 1: the deepest parts of Jupiter could not be photographed directly.
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  Speaker 1: So scientists needed another kind of journey. They needed a
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  Speaker 1: spacecraft capable of listening to Jupiter in a different way,
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  Speaker 1: measuring tiny changes in its gravity, its magnetic environment, and
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  Speaker 1: its atmosphere. and using those changes as clues to what
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  Speaker 1: was happening far below. That spacecraft would become Juno. Juno
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  Speaker 1: was launched in 2011 and arrived at Jupiter in 2016,
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  Speaker 1: beginning a long investigation of the planet from close range.
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  Speaker 1: But before Juno could help reveal the hidden interior, there
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  Speaker 1: was another strange question waiting much closer to the clouds.
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  Speaker 1: What happens to all that water? Because high above Jupiter,
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  Speaker 1: the atmosphere can be unimaginably cold. The upper clouds can
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  Speaker 1: fall below minus 100 degrees Celsius. At first, that sounds
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  Speaker 1: like a place where water should simply freeze and remain frozen.
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  Speaker 1: And yet Jupiter has found a curious way around that expectation. Ammonia,
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  Speaker 1: another chemical substance present in the atmosphere, can mix with
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  Speaker 1: water and change the conditions under which water freezes. In
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  Speaker 1: this strange mixture, Small amounts of liquid water can exist
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  Speaker 1: in places where you might otherwise expect only ice. Tiny
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  Speaker 1: droplets can meet pieces of ice. Particles can collide. Electrical
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  Speaker 1: charges can slowly separate. And eventually, the clouds can release
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  Speaker 1: enormous flashes of lightning. Then some of the water and
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  Speaker 1: ammonia can gather into heavy, slushy particles, falling deeper into
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  Speaker 1: the atmosphere before changing again. The material falls. It melts.
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  Speaker 1: It evaporates. And some of it rises once more. Water falls.
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  Speaker 1: Water changes. Water rises again. The cycle continues quietly inside
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  Speaker 1: the clouds. And now, as you drift a little closer
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  Speaker 1: to Jupiter, you can begin to imagine that its atmosphere
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  Speaker 1: is not a thin decoration painted across a simple planet.
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  Speaker 1: It is an active, layered world. A place where water
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  Speaker 1: can freeze, melt, evaporate and rise again. A place where
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  Speaker 1: lightning can flash inside clouds hundreds of kilometres above deeper regions.
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  Speaker 1: A place where a passing comet once disturbed the atmosphere
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  Speaker 1: enough to give humanity a fleeting glimpse of what lay beneath.
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  Speaker 1: And below those restless clouds, the planet continues downward. There
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  Speaker 1: is still no surface, only deeper atmosphere, greater pressure, more warmth.
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  Speaker 1: and an interior that is waiting quietly below, changing little
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  Speaker 1: by little as you descend. You can imagine yourself drifting
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  Speaker 1: a little closer now, toward the clouds of Jupiter. From
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  Speaker 1: a distance, they looked almost smooth, like broad bands of
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  Speaker 1: pale fabric wrapped around the planet. But as you approach them,
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  Speaker 1: the clouds begin to reveal their movement. There are layers
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  Speaker 1: within layers. currents flowing in different directions, small particles rising
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  Speaker 1: and falling, regions of colder air meeting warmer air, and
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  Speaker 1: tiny pieces of ice moving through the darkness. There is
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  Speaker 1: no solid surface beneath you, no place to stand, no shoreline,
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  Speaker 1: no mountain waiting below. You are simply moving through an
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  Speaker 1: atmosphere that becomes deeper and denser as you go, and
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  Speaker 1: high above this enormous world the temperature can become extraordinarily cold.
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  Speaker 1: Some of the upper cloud layers can fall below minus
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  Speaker 1: 100 degrees Celsius. It is difficult to imagine such coldness,
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  Speaker 1: especially when you remember that Jupiter is also a world
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  Speaker 1: of enormous internal heat. Above you, the clouds can be
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  Speaker 1: intensely cold. Far below, the planet becomes warmer and warmer.
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  Speaker 1: And between these very different regions, matter is constantly changing.
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  Speaker 1: Water is is one of the most familiar substances you know.
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  Speaker 1: On Earth, you can watch it fall as rain, settle
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  Speaker 1: as snow, freeze into ice, and disappear slowly into the
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  Speaker 1: air as vapour. Inside Jupiter's atmosphere, water follows some of
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  Speaker 1: these same patterns, but under conditions that make the entire
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  Speaker 1: process feel strangely unfamiliar. There is water ice high in
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  Speaker 1: the clouds. There are tiny droplets. There are mixtures of
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  Speaker 1: water and ammonia, and ammonia has an unusual effect here.
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  Speaker 1: It can act rather like an antifreeze, changing the conditions
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  Speaker 1: under which water freezes. So even in a region where
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  Speaker 1: the temperature is cold enough to freeze ordinary water, small
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  Speaker 1: amounts of liquid water can still exist when water and
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  Speaker 1: ammonia are mixed together. You can imagine a tiny droplet
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  Speaker 1: suspended inside the clouds. It is not falling quickly, it
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  Speaker 1: is simply hanging there for a moment, surrounded by cold
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  Speaker 1: air and countless other particles. Above it, ice crystals drift.
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  Speaker 1: Around it, the atmosphere moves. Below it, there is only
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  Speaker 1: more cloud. Then the droplet meets a small piece of ice.
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  Speaker 1: The two particles touch. They separate. They touch again. And
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  Speaker 1: through countless tiny collisions like these, electrical charges can gradually
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  Speaker 1: become separated within the cloud. Nothing dramatic needs to happen
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  Speaker 1: at first. The process can be slow, almost invisible. Particle
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  Speaker 1: meets particle. Ice moves against liquid. Small differences accumulate. And eventually,
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  Speaker 1: Enough electrical imbalance can build inside the cloud for the
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  Speaker 1: atmosphere to release it in a flash. Lightning, a brief,
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  Speaker 1: powerful path of electricity, suddenly crosses the cloud. For a moment,
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  Speaker 1: a region that had been almost completely dark becomes bright.
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  Speaker 1: Then the light is gone. The clouds return to darkness,
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  Speaker 1: and the tiny particles continue moving. You can imagine this
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  Speaker 1: happening again and again across Jupiter. sometimes far away from
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  Speaker 1: where you are drifting, sometimes perhaps somewhere beneath you, hidden
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  Speaker 1: inside a deeper layer of cloud. The lightning is only
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  Speaker 1: one part of the process. Something else is happening at
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  Speaker 1: the same time. Some of the water and ammonia can
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  Speaker 1: gather around ice particles and form larger, heavier pieces. They
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  Speaker 1: can become something like enormous soft hailstones, made not from
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  Speaker 1: the familiar ice of an earthstorm, but from a strange
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  Speaker 1: mixture of frozen and partially melted material. These particles begin
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  Speaker 1: to fall, and as they fall they enter warmer regions.
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  Speaker 1: The deeper they travel, the more the surrounding conditions change.
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  Speaker 1: Ice can soften. Frozen material can melt. Liquid can evaporate.
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  Speaker 1: The particle changes again, and material that was once falling
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  Speaker 1: can eventually return upward as vapour. So the movement is
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  Speaker 1: not simply downward. It is a quiet cycle. Something forms
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  Speaker 1: high above. It begins to fall. It changes as it descends.
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  Speaker 1: Then part of it rises again. And the process begins
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  Speaker 1: once more. Water falls. Water changes. Water rises. Again and again.
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  Speaker 1: There is something almost peaceful about this cycle when you
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  Speaker 1: remove the scale from it. You could imagine a single
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  Speaker 1: tiny particle making the journey. It forms inside a cloud.
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  Speaker 1: It begins to fall. The temperature changes around it. The
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  Speaker 1: pressure changes. The particle changes with them. Then, much deeper down,
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  Speaker 1: it becomes part of the atmosphere in another form. Later,
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  Speaker 1: it may rise again, and somewhere far above, it can
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  Speaker 1: become part of a cloud once more. Jupiter has no
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  Speaker 1: ordinary rainfall, in the sense that you might imagine, from
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  Speaker 1: standing beneath an Earth cloud. There is no ground waiting
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  Speaker 1: to receive the rain. There is no forest beneath it.
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  Speaker 1: No ocean surface. No quiet field. The falling material simply
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  Speaker 1: continues into deeper and denser parts of the planet. The
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  Speaker 1: atmosphere itself becomes the world. And this is one of
• 23:21
  Speaker 1: the ideas worth resting with for a moment. On Earth,
• 23:25
  Speaker 1: when you look at a cloud, you naturally imagine the
• 23:27
  Speaker 1: space beneath it. You imagine sky, then land. But on Jupiter,
• 23:32
  Speaker 1: when you look at a cloud, you are looking toward
• 23:35
  Speaker 1: more Jupiter. Below the cloud is another layer, and below that, another.
• 23:41
  Speaker 1: The deeper you go, the warmer and denser the material becomes. Eventually,
• 23:47
  Speaker 1: the distinction between what you would call air and what
• 23:50
  Speaker 1: you would call liquid begins to lose its familiar meaning.
• 23:54
  Speaker 1: But for now, you are still among the clouds. The
• 23:58
  Speaker 1: cold air moves gently around you. Tiny droplets drift. Ice
• 24:03
  Speaker 1: particles fall. Somewhere in the distance, lightning briefly illuminates the darkness.
• 24:10
  Speaker 1: Then everything becomes quiet again. You can let the flash disappear.
• 24:15
  Speaker 1: You can let the sound of the storm fade into
• 24:17
  Speaker 1: the background. There is nothing you need to follow. Nothing
• 24:21
  Speaker 1: you need to calculate. You are safe. There is nothing
• 24:25
  Speaker 1: to do. Just listen and drift through this strange atmosphere.
• 24:30
  Speaker 1: Far below, Jupiter continues to grow warmer. The enormous weight
• 24:35
  Speaker 1: of the planet presses inward. The material becomes increasingly compressed,
• 24:40
  Speaker 1: and the simple clouds you first saw from space are
• 24:43
  Speaker 1: gradually becoming something else. The storm above is still part
• 24:47
  Speaker 1: of Jupiter. The water is still part of Jupiter. The
• 24:51
  Speaker 1: ammonia is still part of Jupiter. But the deeper you go,
• 24:55
  Speaker 1: the more these familiar substances begin to behave in unfamiliar ways.
• 25:00
  Speaker 1: and somewhere within all this slow movement, the great storms
• 25:04
  Speaker 1: of Jupiter are reaching farther downward than the eye can see.
• 25:09
  Speaker 1: One of them has been turning for a very long time.
• 25:12
  Speaker 1: It is enormous enough to make the storms of Earth
• 25:14
  Speaker 1: seem almost delicate, and as you drift toward it, the
• 25:18
  Speaker 1: clouds begin to gather into a much larger shape, moving
• 25:22
  Speaker 1: slowly through the atmosphere, carrying with them one of Jupiter's
• 25:26
  Speaker 1: most famous and mysterious features. You can drift a little
• 25:32
  Speaker 1: farther now, toward the enormous storm that has been turning
• 25:36
  Speaker 1: inside Jupiter's atmosphere for a very long time. From far away,
• 25:41
  Speaker 1: the great red spot looks almost simple, a reddish oval
• 25:46
  Speaker 1: floating among pale bands of cloud. But as you approach it,
• 25:50
  Speaker 1: the shape begins to lose its simplicity. It is not
• 25:54
  Speaker 1: a painted mark on the surface of Jupiter. There is
• 25:57
  Speaker 1: no surface there. It is a vast region of moving atmosphere.
• 26:01
  Speaker 1: a great circulation of clouds and gases, turning within the
• 26:05
  Speaker 1: deeper layers of the planet. You can imagine yourself floating
• 26:09
  Speaker 1: above it for a moment. The clouds beneath you move
• 26:12
  Speaker 1: slowly across your field of view, not slowly in the
• 26:15
  Speaker 1: sense that nothing is happening, but slowly enough that you
• 26:18
  Speaker 1: can watch the shape change without needing to follow every detail.
• 26:23
  Speaker 1: There is no urgency. You are safe. There is nothing
• 26:27
  Speaker 1: to do. You can simply drift above the storm, and
• 26:31
  Speaker 1: listen to the quiet idea of motion. The Great Red
• 26:34
  Speaker 1: Spot is thousands of kilometres wide. It is large enough that,
• 26:39
  Speaker 1: if you could somehow look down from above it with
• 26:42
  Speaker 1: familiar objects nearby, the scale would become difficult to hold
• 26:46
  Speaker 1: in your mind. Yet from Jupiter's distance, even something this
• 26:51
  Speaker 1: enormous can appear like a small coloured shape. That is
• 26:55
  Speaker 1: one of the strange things about planets. Scale changes depending
• 26:59
  Speaker 1: on how far away you are, A storm can be
• 27:02
  Speaker 1: larger than an entire world you know, and still appear
• 27:05
  Speaker 1: as only one feature among many. You can let that
• 27:09
  Speaker 1: thought become soft, a vast storm, a small shape, a
• 27:14
  Speaker 1: tremendous movement hidden inside a distant planet. And the red
• 27:18
  Speaker 1: colour itself is part of the mystery. The clouds of
• 27:21
  Speaker 1: Jupiter are exposed to invisible ultraviolet light from the Sun.
• 27:26
  Speaker 1: This light can interact with chemicals high in the atmosphere,
• 27:30
  Speaker 1: and help create complex substances that absorb and scatter light differently.
• 27:36
  Speaker 1: Some of these chemical changes contribute to the reddish appearance
• 27:40
  Speaker 1: you see, so the colour is not simply the colour
• 27:43
  Speaker 1: of some ordinary material floating inside the storm. It is
• 27:47
  Speaker 1: partly a story written by sunlight, chemistry, and the atmosphere itself.
• 27:52
  Speaker 1: You do not need to hold all of those details.
• 27:56
  Speaker 1: You can simply imagine sunlight arriving from far away, touching
• 28:00
  Speaker 1: the upper clouds, and quietly changing tiny molecules within them.
• 28:05
  Speaker 1: A little light, a little chemistry, a little colour, and
• 28:09
  Speaker 1: beneath that colour the storm continues turning. The great red
• 28:14
  Speaker 1: spot also rises above the surrounding clouds. It is not
• 28:18
  Speaker 1: merely a flat patch, its cloud tops can extend higher
• 28:22
  Speaker 1: than the nearby atmosphere, giving the storm a shape with
• 28:26
  Speaker 1: real depth. And below those visible clouds, the circulation reaches downward.
• 28:32
  Speaker 1: Measurements from spacecraft have shown that the storm extends hundreds
• 28:35
  Speaker 1: of kilometres into Jupiter's atmosphere. That means the red oval
• 28:40
  Speaker 1: you see from space is only the upper expression of
• 28:43
  Speaker 1: something much deeper. You can imagine looking at an ocean
• 28:46
  Speaker 1: from above and seeing a patch of moving water. The
• 28:50
  Speaker 1: patch would be visible at the surface. But beneath it,
• 28:54
  Speaker 1: currents could continue downward. connecting the surface movement to deeper layers,
• 28:59
  Speaker 1: Jupiter's storm is stranger still, because there is no ordinary
• 29:03
  Speaker 1: ocean surface beneath it. There is only atmosphere becoming denser,
• 29:08
  Speaker 1: layer after layer, cloud after cloud, pressure increasing as you descend.
• 29:15
  Speaker 1: So when you imagine the Great Red Spot, it can
• 29:17
  Speaker 1: help to imagine not a mark, but a column of movement.
• 29:22
  Speaker 1: A broad region extending sideways across thousands of kilometres, and
• 29:26
  Speaker 1: reaching downward through hundreds of kilometres of atmosphere. Above you, sunlight,
• 29:32
  Speaker 1: around you, clouds, below you, increasing pressure, and through it all, motion.
• 29:38
  Speaker 1: The winds inside Jupiter are enormous. Bands of atmosphere move
• 29:43
  Speaker 1: around the planet in different directions, and the great red
• 29:47
  Speaker 1: spot exists within this larger pattern of circulation. You might
• 29:51
  Speaker 1: imagine yourself carried gently along one of these currents. There
• 29:55
  Speaker 1: is no road, no edge. No beginning that you can
• 29:59
  Speaker 1: easily point toward. Just air moving around air. Cloud moving
• 30:04
  Speaker 1: around cloud. A storm maintaining its shape while the individual
• 30:08
  Speaker 1: particles inside it continue to change. This is another quiet
• 30:13
  Speaker 1: paradox of Jupiter. The storm can remain recognisable while everything
• 30:18
  Speaker 1: inside it is moving. The clouds do not have to
• 30:21
  Speaker 1: remain the same particles. The gases do not have to
• 30:24
  Speaker 1: remain in the same places. The atmosphere can change continuously,
• 30:29
  Speaker 1: while the larger pattern continues. Like a slow whirlpool, the
• 30:34
  Speaker 1: form can persist even though the water within it is
• 30:37
  Speaker 1: always moving. Except here, there is no water surface. There
• 30:42
  Speaker 1: is only Jupiter. And the deeper you drift, the more
• 30:45
  Speaker 1: you begin to notice that the atmosphere itself is changing character.
• 30:49
  Speaker 1: The upper clouds are cold, very cold. But farther down,
• 30:54
  Speaker 1: the pressure becomes greater, because more and more material rests
• 30:58
  Speaker 1: above you. That enormous weight presses inward, and as you
• 31:02
  Speaker 1: descend the temperature rises. The atmosphere becomes denser. The familiar
• 31:07
  Speaker 1: picture of a gas giant begins to fade. You are
• 31:11
  Speaker 1: no longer imagining a huge empty space filled with light gas.
• 31:16
  Speaker 1: You are beginning to imagine a world where the atmosphere
• 31:18
  Speaker 1: itself becomes a thick, compressed substance. The great red spot
• 31:23
  Speaker 1: is therefore more than a beautiful feature. It is also
• 31:27
  Speaker 1: a kind of window. Through it, you can sense the
• 31:30
  Speaker 1: enormous depth of Jupiter. You see clouds at the top.
• 31:34
  Speaker 1: You see a storm moving through them. You learn that
• 31:37
  Speaker 1: the storm reaches downward. And then you begin to wonder
• 31:41
  Speaker 1: what lies beneath even that. Because the Great Red Spot
• 31:44
  Speaker 1: does not end where its visible colour ends. Its movement
• 31:48
  Speaker 1: continues into deeper layers. The deeper layers become warmer. The
• 31:53
  Speaker 1: pressure becomes greater. And eventually, The hydrogen that filled your
• 31:57
  Speaker 1: imagination as an invisible gas begins to behave very differently.
• 32:03
  Speaker 1: It becomes increasingly dense. It begins to lose the familiar
• 32:07
  Speaker 1: quality of an ordinary gas. And farther down still, it
• 32:11
  Speaker 1: becomes something that would seem almost impossible if you only
• 32:14
  Speaker 1: knew hydrogen from Earth. A vast region of dense liquid hydrogen.
• 32:20
  Speaker 1: So for now, you can remain above the storm. Watch
• 32:24
  Speaker 1: the red clouds turn. Watch the pale bands move around them.
• 32:28
  Speaker 1: Let the distant sunlight fade softly across the atmosphere. You
• 32:32
  Speaker 1: do not need to solve the storm. You do not
• 32:35
  Speaker 1: need to know exactly how every current moves. You can
• 32:38
  Speaker 1: simply notice that Jupiter's weather does not stop at the
• 32:42
  Speaker 1: clouds you can see. It reaches downward and downward and downward.
• 32:47
  Speaker 1: The visible planet is becoming only the beginning. Somewhere beneath
• 32:51
  Speaker 1: the swirling storm, the pressure continues to rise. The temperature
• 32:56
  Speaker 1: continues to increase, and the simple gas of hydrogen is
• 33:00
  Speaker 1: slowly being transformed by the enormous weight of the planet itself.
• 33:05
  Speaker 1: You can drift with that thought for a while. Above you,
• 33:08
  Speaker 1: the great red spot continues its patient turning. Below you,
• 33:13
  Speaker 1: there is more Jupiter, and somewhere in that growing darkness,
• 33:17
  Speaker 1: hydrogen is beginning to gather into a vast, quiet, liquid world,
• 33:22
  Speaker 1: waiting beneath the clouds. You can let yourself drift beneath
• 33:28
  Speaker 1: the great red spot now. The red clouds are slowly
• 33:31
  Speaker 1: passing above you. The pale bands of Jupiter stretch away
• 33:35
  Speaker 1: into the distance, and the familiar patterns of the upper
• 33:38
  Speaker 1: atmosphere begin to fade behind you. You are moving downward,
• 33:43
  Speaker 1: very gently. There is no sudden change. Nothing announces the transition.
• 33:49
  Speaker 1: The atmosphere simply becomes deeper, denser, and warmer as you
• 33:54
  Speaker 1: continue to descend. Above you, The clouds still exist. But
• 33:59
  Speaker 1: beneath them, there are fewer familiar landmarks. There is no ground.
• 34:04
  Speaker 1: There is no mountain. There is no hidden continent waiting below.
• 34:08
  Speaker 1: There is only more Jupiter. And as you move deeper,
• 34:12
  Speaker 1: you begin to feel the importance of something that is
• 34:14
  Speaker 1: almost impossible to notice from space. Weight. All around you
• 34:19
  Speaker 1: is material. Above you is material. And above that material
• 34:23
  Speaker 1: is more material. the enormous mass of Jupiter presses inward
• 34:28
  Speaker 1: under the planet's gravity. The deeper you go, the more
• 34:31
  Speaker 1: of the atmosphere rests above you, and so the pressure increases.
• 34:36
  Speaker 1: You can imagine it very softly, as if the entire
• 34:39
  Speaker 1: planet were settling around you, not crushing you in some
• 34:43
  Speaker 1: sudden moment, but gradually changing the environment with every layer
• 34:47
  Speaker 1: you pass. The temperature rises too. The cold upper clouds
• 34:52
  Speaker 1: are far behind now, The deeper atmosphere is warmer, and
• 34:55
  Speaker 1: the hydrogen that once behaved like a thin gas is
• 34:59
  Speaker 1: becoming increasingly crowded. Hydrogen is the lightest and most abundant
• 35:04
  Speaker 1: element in Jupiter. In the upper atmosphere, you can imagine
• 35:08
  Speaker 1: it as countless tiny particles moving freely through a vast space.
• 35:14
  Speaker 1: But deep inside the planet, there is much less empty
• 35:17
  Speaker 1: space between those particles. The enormous pressure brings them closer together.
• 35:22
  Speaker 1: The atmosphere becomes thick, then denser, then denser still, and
• 35:28
  Speaker 1: eventually the word gas begins to feel less useful. You
• 35:32
  Speaker 1: have crossed into a region where hydrogen exists as a
• 35:35
  Speaker 1: dense liquid. There is no sharp shoreline marking the boundary,
• 35:40
  Speaker 1: no sign saying that the atmosphere has ended and the
• 35:43
  Speaker 1: ocean has begun. Instead, the change happens gradually. Gas becomes denser.
• 35:50
  Speaker 1: Denser material becomes more fluid. And eventually, deep beneath the
• 35:55
  Speaker 1: visible clouds, hydrogen behaves as a liquid. A liquid without
• 35:59
  Speaker 1: a familiar surface. A liquid with no beach. No waves
• 36:03
  Speaker 1: under a sky. No place where you could stand beside it.
• 36:07
  Speaker 1: It is simply part of Jupiter. A vast interior region
• 36:11
  Speaker 1: of hydrogen, held together by the immense pressure of the planet.
• 36:16
  Speaker 1: You can imagine yourself drifting through it. The darkness around
• 36:20
  Speaker 1: you is deeper now. The material is much denser than
• 36:23
  Speaker 1: the air you know. Movement is slower in your imagination, heavier, quieter.
• 36:29
  Speaker 1: The hydrogen surrounds you in every direction. There is no
• 36:33
  Speaker 1: clear line between where the atmosphere ends and where the
• 36:37
  Speaker 1: liquid begins. The whole planet has become a gradual transition.
• 36:42
  Speaker 1: Above you, thinner hydrogen. Below you, denser hydrogen. Farther down,
• 36:48
  Speaker 1: warmer hydrogen. And deeper still, hydrogen entering another extraordinary state.
• 36:54
  Speaker 1: But for now, stay here. Stay with the liquid, because
• 36:58
  Speaker 1: this hidden ocean is enormous. The region of liquid hydrogen
• 37:03
  Speaker 1: extends for thousands upon thousands of kilometres. In the source
• 37:07
  Speaker 1: material for this journey, the liquid region is described as
• 37:11
  Speaker 1: reaching roughly 20,000 kilometres in depth. That is difficult to
• 37:15
  Speaker 1: picture using earthly distances. You can simply imagine descending for
• 37:20
  Speaker 1: a very long time, long after the clouds have disappeared
• 37:23
  Speaker 1: from view, long after the sunlight has become irrelevant, long
• 37:28
  Speaker 1: after the atmosphere above has become a distant memory. You
• 37:31
  Speaker 1: continue moving through hydrogen, and the deeper you go, the
• 37:35
  Speaker 1: greater the pressure becomes. The warmth increases, the material becomes
• 37:41
  Speaker 1: more compressed, the liquid becomes part of an even deeper transformation.
• 37:46
  Speaker 1: On Earth, Hydrogen can become liquid too, but the method
• 37:51
  Speaker 1: is very different. You would normally need extraordinary cold, temperatures
• 37:56
  Speaker 1: close to the deepest cold you can imagine. Jupiter does
• 38:00
  Speaker 1: something almost opposite. It does not need to cool hydrogen
• 38:03
  Speaker 1: into a liquid. Instead, the enormous pressure inside the planet
• 38:08
  Speaker 1: changes the behaviour of the hydrogen. The weight of Jupiter
• 38:12
  Speaker 1: itself helps create the conditions. This is one of the
• 38:16
  Speaker 1: quiet wonders of the planet. The same gravity that keeps
• 38:19
  Speaker 1: Jupiter together also helps transform its interior. The planet's enormous
• 38:24
  Speaker 1: mass creates pressure. The pressure changes matter, and matter changes
• 38:29
  Speaker 1: the way the planet exists. You can let those three
• 38:33
  Speaker 1: ideas repeat gently. Mass creates pressure. Pressure changes matter. Matter
• 38:38
  Speaker 1: creates the hidden world beneath the clouds. Nothing here needs
• 38:42
  Speaker 1: to happen quickly. The transformation is simply the natural consequence
• 38:47
  Speaker 1: of being deep inside such a massive planet. Imagine now
• 38:51
  Speaker 1: that you could look upward. You would see no clouds,
• 38:54
  Speaker 1: no blue sky, no stars. The upper atmosphere would be
• 38:58
  Speaker 1: hidden by tens of thousands of kilometres of material. And
• 39:02
  Speaker 1: below you, the liquid hydrogen continues. Quiet, dense, warm, vast.
• 39:09
  Speaker 1: There is something strangely peaceful about a world without a surface.
• 39:13
  Speaker 1: On Earth, almost every landscape is defined by boundaries. Land
• 39:18
  Speaker 1: meets water, water meets air, air meets space. But deep
• 39:24
  Speaker 1: inside Jupiter, those boundaries become softer. There is no obvious
• 39:28
  Speaker 1: line separating one environment from another. The planet simply changes
• 39:33
  Speaker 1: gradually as you move. You can drift through one layer
• 39:37
  Speaker 1: and then another. You may not notice the exact moment
• 39:40
  Speaker 1: when one state of matter becomes another. And perhaps that
• 39:44
  Speaker 1: is fitting for Jupiter. It is a planet that looks
• 39:47
  Speaker 1: simple from a great distance. A large sphere of clouds,
• 39:52
  Speaker 1: a striped world, a gas giant. But once you enter it,
• 39:57
  Speaker 1: every simple description begins to soften. The clouds are not
• 40:01
  Speaker 1: the whole planet. The gas is not always gas. The
• 40:05
  Speaker 1: atmosphere becomes liquid, and the liquid does not remain ordinary
• 40:09
  Speaker 1: liquid forever. Farther down, the pressure becomes millions of times
• 40:14
  Speaker 1: greater than the pressure at Earth's surface. The temperature rises
• 40:18
  Speaker 1: toward thousands of degrees. Under these conditions, hydrogen begins to
• 40:23
  Speaker 1: behave in a way that is even stranger. Its electrons
• 40:26
  Speaker 1: can move much more freely, and when that happens, the
• 40:30
  Speaker 1: liquid can carry electricity. The quiet ocean beneath you is
• 40:34
  Speaker 1: becoming something new, a liquid that behaves, in some ways,
• 40:39
  Speaker 1: like a metal. You do not need to hurry toward it.
• 40:43
  Speaker 1: You can remain here for another moment. surrounded by dense hydrogen,
• 40:47
  Speaker 1: held inside the immense weight of Jupiter. Above you, the
• 40:51
  Speaker 1: clouds continue drifting. Below you, the planet grows warmer. The
• 40:56
  Speaker 1: boundary between gas and liquid has already faded, and somewhere
• 41:00
  Speaker 1: farther beneath you, the liquid itself is beginning to change.
• 41:04
  Speaker 1: The darkness is becoming deeper, the pressure is becoming greater,
• 41:08
  Speaker 1: and hydrogen, still liquid, is approaching one of the strangest
• 41:12
  Speaker 1: states of matter known to exist inside a planet. A
• 41:16
  Speaker 1: state where a liquid can conduct electricity. A hidden world
• 41:20
  Speaker 1: of liquid metal, quietly turning beneath Jupiter's clouds. You are
• 41:27
  Speaker 1: still drifting deep inside Jupiter. The clouds are far above
• 41:31
  Speaker 1: you now. The familiar atmosphere has gradually become something much denser,
• 41:36
  Speaker 1: warmer and quieter. And around you is the enormous liquid
• 41:41
  Speaker 1: region of hydrogen that fills a great portion of the planet.
• 41:45
  Speaker 1: There is no surface here. No horizon. No place where
• 41:49
  Speaker 1: the liquid begins in a way you could easily point to.
• 41:52
  Speaker 1: The change happened gradually, almost without announcement. The hydrogen simply
• 41:58
  Speaker 1: became denser and denser as you descended. And now, the
• 42:02
  Speaker 1: pressure is becoming something difficult to imagine. Millions of times
• 42:06
  Speaker 1: greater than the pressure at the surface of Earth. The
• 42:09
  Speaker 1: temperature is rising too, thousands of degrees. Yet somehow, hydrogen
• 42:15
  Speaker 1: remains liquid. And as you continue downward, something even stranger
• 42:20
  Speaker 1: begins to happen. The hydrogen starts behaving like a metal.
• 42:24
  Speaker 1: You can pause here for a moment. A liquid metal.
• 42:28
  Speaker 1: It sounds almost contradictory. When you think of metal, perhaps
• 42:32
  Speaker 1: you imagine something solid, something cool and heavy in your hand,
• 42:37
  Speaker 1: something with a definite shape. But deep inside Jupiter, metallic
• 42:41
  Speaker 1: hydrogen is not a solid object like a piece of iron.
• 42:46
  Speaker 1: It remains a liquid. It flows. It moves. It surrounds you.
• 42:51
  Speaker 1: And yet, its electrical behaviour is very different from the
• 42:54
  Speaker 1: hydrogen you know near the top of the atmosphere. The
• 42:58
  Speaker 1: reason lies in something very small, smaller than anything you
• 43:01
  Speaker 1: could see. The electrons associated with hydrogen are normally held
• 43:05
  Speaker 1: close to their atoms. But under the enormous pressure deep
• 43:09
  Speaker 1: inside Jupiter, the atoms are pushed so close together that
• 43:13
  Speaker 1: the electrons can move much more freely. They are no
• 43:17
  Speaker 1: longer confined in quite the same familiar way. They can
• 43:21
  Speaker 1: travel through the dense liquid. And because these tiny charged
• 43:24
  Speaker 1: particles can move, the liquid hydrogen can carry electricity. You
• 43:29
  Speaker 1: do not need to picture sparks. There is no bright
• 43:32
  Speaker 1: flash around you. The process is much quieter. Invisible movement
• 43:37
  Speaker 1: inside an enormous liquid. Tiny charged particles moving through a
• 43:42
  Speaker 1: vast planetary interior. Currents forming where you cannot see them.
• 43:47
  Speaker 1: And from these hidden currents comes one of Jupiter's most
• 43:50
  Speaker 1: remarkable features. Its magnetic field. You have already been drifting
• 43:56
  Speaker 1: through Jupiter's clouds. You have watched storms turn. You have
• 44:01
  Speaker 1: moved through liquid hydrogen. Now you can begin to sense
• 44:04
  Speaker 1: that the planet is connected to something much larger than
• 44:08
  Speaker 1: its visible atmosphere. A magnetic field surrounds Jupiter and extends
• 44:13
  Speaker 1: far beyond the planet itself. It reaches outward into space,
• 44:18
  Speaker 1: forming an enormous invisible region around the world. You cannot
• 44:23
  Speaker 1: see it directly, but its presence is real, and deep
• 44:27
  Speaker 1: inside the planet, the movement of electrically conducting material helps
• 44:31
  Speaker 1: create it. So you can imagine Jupiter from the inside outward,
• 44:36
  Speaker 1: at the centre, enormous pressure. Around that, vast regions of
• 44:41
  Speaker 1: dense material. Farther outward, liquid hydrogen. And within some of
• 44:46
  Speaker 1: that liquid, electrons moving freely enough to carry electrical currents.
• 44:51
  Speaker 1: Those currents contribute to the magnetic field. The field extends outward,
• 44:57
  Speaker 1: and Jupiter quietly reaches into space without ever physically touching it.
• 45:02
  Speaker 1: you can let that image become soft, a dark planet,
• 45:06
  Speaker 1: a warm liquid interior, invisible electrical movement, and an invisible
• 45:11
  Speaker 1: magnetic presence surrounding everything. There is no need for a
• 45:16
  Speaker 1: dramatic moment. The magnetism is simply there, quietly produced by
• 45:21
  Speaker 1: motion deep below, and the deeper you remain, the more
• 45:25
  Speaker 1: extraordinary the scale becomes. Jupiter's metallic hydrogen occupies a huge
• 45:31
  Speaker 1: portion of the planet's interior. The region is not a
• 45:34
  Speaker 1: thin layer. It is not some small pocket hidden near
• 45:38
  Speaker 1: the centre. It makes up a substantial part of the planet.
• 45:42
  Speaker 1: So when you picture Jupiter from far away, you might
• 45:45
  Speaker 1: imagine clouds surrounding a mostly empty ball of gas. But
• 45:50
  Speaker 1: now you know to let that picture soften. The clouds
• 45:53
  Speaker 1: are only the beginnings. Below them is dense hydrogen. Below that,
• 45:59
  Speaker 1: hydrogen becomes metallic, and through this enormous liquid region, electricity
• 46:04
  Speaker 1: can move. You can imagine drifting slowly through it. The
• 46:09
  Speaker 1: temperature is high, but there is no flame. The pressure
• 46:13
  Speaker 1: is immense, but there is no sudden impact. Everything is
• 46:17
  Speaker 1: held in a strange, quiet balance. The liquid moves. The
• 46:22
  Speaker 1: electrons move. The planet turns. And from all this movement
• 46:26
  Speaker 1: comes a magnetic field that reaches far beyond the clouds.
• 46:31
  Speaker 1: Even here, deep inside Jupiter, the same pattern continues. Movement
• 46:37
  Speaker 1: creates change. Change creates another form of movement. And the
• 46:42
  Speaker 1: planet remains connected from its deepest interior to the darkness
• 46:46
  Speaker 1: around it. If you could somehow look outward from this
• 46:50
  Speaker 1: hidden region, there would be no stars visible. Too much
• 46:53
  Speaker 1: material lies above you. The sunlight that illuminated the upper
• 46:57
  Speaker 1: clouds would be unimaginably far away. You would be surrounded
• 47:02
  Speaker 1: by darkness and warmth. But the darkness would not mean emptiness.
• 47:07
  Speaker 1: There would be countless particles moving around you. Hydrogen would
• 47:11
  Speaker 1: still be flowing. Electrons would still be travelling. Energy would
• 47:16
  Speaker 1: still be moving through the planet. It is a quiet
• 47:19
  Speaker 1: kind of activity, almost invisible, and perhaps that is what
• 47:23
  Speaker 1: makes it so fascinating. Jupiter's greatest features do not all
• 47:28
  Speaker 1: live on its surface. Some of them are born where
• 47:31
  Speaker 1: no human eye could ever look directly. The storms above
• 47:35
  Speaker 1: are connected to deeper atmospheric layers. The atmosphere becomes liquid,
• 47:41
  Speaker 1: the liquid becomes electrically conducting, and that hidden electrical movement
• 47:46
  Speaker 1: helps create the enormous magnetic field extending into space. You
• 47:51
  Speaker 1: can rest with that sequence for a while. Clouds, Liquid. Electricity. Magnetism.
• 47:59
  Speaker 1: One layer leading gently into another. And still you have
• 48:03
  Speaker 1: not reached the centre. There is more material below. Much more.
• 48:08
  Speaker 1: The pressure continues to increase. The temperature continues to rise.
• 48:13
  Speaker 1: And somewhere beneath this vast region of metallic hydrogen is
• 48:17
  Speaker 1: a central region that does not behave quite like the
• 48:20
  Speaker 1: compact planetary core you might expect. For a long time,
• 48:24
  Speaker 1: scientists imagined Jupiter with a relatively clear centre, a dense
• 48:29
  Speaker 1: ball of rock and metal hidden beneath the hydrogen. But
• 48:32
  Speaker 1: the deeper measurements from spacecraft have suggested something softer and stranger.
• 48:38
  Speaker 1: The centre may not have a clean edge at all.
• 48:41
  Speaker 1: It may be broad, diffuse, blended, a region where rocky
• 48:46
  Speaker 1: and metallic material gradually mixes into the surrounding hydrogen, a
• 48:51
  Speaker 1: core that without a simple boundary. You can drift toward
• 48:56
  Speaker 1: that hidden centre now. Not quickly. There is no need.
• 49:00
  Speaker 1: The magnetic field continues quietly around you. The metallic hydrogen
• 49:05
  Speaker 1: continues to flow. And beneath it, the planet is becoming
• 49:09
  Speaker 1: stranger still. Somewhere in the darkness ahead is Jupiter's soft-edged heart,
• 49:14
  Speaker 1: a central region that may stretch much farther outward than
• 49:18
  Speaker 1: anyone once expected. You are safe. There is nothing to do.
• 49:23
  Speaker 1: Just listen and drift. The clouds are impossibly far above
• 49:27
  Speaker 1: you now. The liquid hydrogen surrounds you, and beneath your
• 49:31
  Speaker 1: slow path through this electrically conducting ocean, the hidden centre
• 49:36
  Speaker 1: of Jupiter waits without a sharp boundary. without a simple shape,
• 49:40
  Speaker 1: and without a completely settled explanation. Perhaps, in the quiet darkness,
• 49:46
  Speaker 1: that uncertainty is part of the beauty. You have travelled
• 49:52
  Speaker 1: a very long way into Jupiter now. Far above you
• 49:55
  Speaker 1: are the clouds. Far above those clouds is the sunlight.
• 49:59
  Speaker 1: Far above the sunlight is the quiet darkness of space.
• 50:03
  Speaker 1: But down here, none of that is visible. You are
• 50:07
  Speaker 1: surrounded by warmth and pressure, by material packed closely together,
• 50:12
  Speaker 1: by a world that has slowly changed as you descended.
• 50:15
  Speaker 1: The liquid hydrogen is still around you. The metallic hydrogen
• 50:19
  Speaker 1: is still flowing. But something about the environment is beginning
• 50:23
  Speaker 1: to feel different. You are approaching the centre. For a
• 50:27
  Speaker 1: long time, scientists imagined that this journey would eventually bring
• 50:31
  Speaker 1: you to something very simple. A solid core. a compact,
• 50:36
  Speaker 1: dense object hidden at the heart of Jupiter, something made
• 50:40
  Speaker 1: mostly from rock and metal, something perhaps roughly comparable in
• 50:44
  Speaker 1: size to Earth. It was an appealing picture. You could
• 50:48
  Speaker 1: imagine Jupiter as a great layered world, clouds on the outside,
• 50:53
  Speaker 1: liquid hydrogen beneath them, metallic hydrogen deeper still, and then,
• 50:59
  Speaker 1: at the very centre, a solid ball, a clear boundary,
• 51:03
  Speaker 1: one layer ending, Another beginning. It is an easy picture
• 51:08
  Speaker 1: to draw, but Jupiter does not seem to follow that
• 51:11
  Speaker 1: picture quite so neatly. The deeper measurements suggest that its
• 51:15
  Speaker 1: centre may be much softer in structure. Not soft in
• 51:19
  Speaker 1: the sense of being cool or delicate. This is still
• 51:22
  Speaker 1: an unimaginably hot and compressed environment. Soft, here, simply means
• 51:28
  Speaker 1: that the boundary is not clear. The dense central material
• 51:32
  Speaker 1: does not seem to end at one precise place. Instead,
• 51:36
  Speaker 1: the transition can stretch outward. Rock and metal become mixed
• 51:40
  Speaker 1: with the surrounding material. The centre gradually becomes less like
• 51:44
  Speaker 1: a single object and more like a broad region. A
• 51:48
  Speaker 1: diffuse heart. A fuzzy centre. You can let that phrase
• 51:52
  Speaker 1: rest gently in your mind. A heart without a sharp edge.
• 51:56
  Speaker 1: A centre without a simple boundary. You are still moving inward.
• 52:01
  Speaker 1: The metallic hydrogen around you becomes increasingly mixed with heavier material. Rock. Metal.
• 52:08
  Speaker 1: Dense liquid. Material that has been carried toward the centre
• 52:12
  Speaker 1: by Jupiter's enormous gravity. There is no clean wall separating
• 52:17
  Speaker 1: one substance from another. Instead, the transition unfolds gradually. The
• 52:23
  Speaker 1: familiar layers begin to overlap, and this is where the
• 52:26
  Speaker 1: old picture of Jupiter begins to fade. Imagine that you
• 52:30
  Speaker 1: were looking for a small solid sphere at the exact centre.
• 52:33
  Speaker 1: You might expect to reach a point where everything suddenly changes.
• 52:38
  Speaker 1: One moment, liquid metal. The next moment, solid rock and metal.
• 52:43
  Speaker 1: But instead, the change appears to be spread across a
• 52:46
  Speaker 1: much larger region. The central material may extend to an
• 52:49
  Speaker 1: astonishing fraction of Jupiter's radius. The source material describes the
• 52:55
  Speaker 1: fuzzy core as spanning roughly half of the planet's radius.
• 52:59
  Speaker 1: You can pause there. Half the radius of Jupiter. Not
• 53:03
  Speaker 1: half the diameter. Half the distance from the centre toward
• 53:06
  Speaker 1: the outside. A huge region. A central area so broad
• 53:11
  Speaker 1: that the word core begins to feel different from the
• 53:14
  Speaker 1: way you normally use it. On Earth, when you hear
• 53:17
  Speaker 1: the word core, you may imagine a compact centre hidden
• 53:21
  Speaker 1: beneath many layers of rock. Jupiter offers something stranger. Its
• 53:26
  Speaker 1: centre may be more like a gradual blending There is
• 53:29
  Speaker 1: dense material, there is rock, there is metal, there is
• 53:33
  Speaker 1: surrounding liquid, and the boundaries between them are not perfectly sharp.
• 53:38
  Speaker 1: You can imagine yourself drifting through this region without ever
• 53:42
  Speaker 1: crossing a single obvious line. The material around you changes slowly.
• 53:47
  Speaker 1: A little more rock here, a little more metal there.
• 53:51
  Speaker 1: More dense material as you continue inward, less of the
• 53:54
  Speaker 1: familiar hydrogen. more of the heavy ingredients that gravity has
• 53:58
  Speaker 1: gathered toward the centre. Everything is moving under enormous pressure.
• 54:03
  Speaker 1: Everything is compressed. Everything is part of the same planet.
• 54:07
  Speaker 1: And perhaps the strangest part is that scientists still do
• 54:10
  Speaker 1: not know exactly why Jupiter's centre looks this way. One
• 54:15
  Speaker 1: possibility begins very early in the history of the solar system.
• 54:19
  Speaker 1: Long before Jupiter looked the way it does now, There
• 54:22
  Speaker 1: may have been a time when the young planet was
• 54:24
  Speaker 1: still gathering material. The early solar system was filled with
• 54:28
  Speaker 1: growing worlds, pieces of rock and metal moving through a
• 54:32
  Speaker 1: young planetary environment. And according to one possible explanation, a
• 54:37
  Speaker 1: very large rocky planet may once have encountered young Jupiter.
• 54:42
  Speaker 1: The object described in the source material could have been
• 54:45
  Speaker 1: around ten times the size of Earth. And if such
• 54:49
  Speaker 1: a world collided with Jupiter … The energy of that
• 54:52
  Speaker 1: enormous encounter could have disturbed the young planet's original centre.
• 54:57
  Speaker 1: Rock and metal from the original core could have been
• 55:00
  Speaker 1: scattered outward. The once compact centre could have become diluted.
• 55:06
  Speaker 1: The boundaries could have been blurred. And over an enormous
• 55:09
  Speaker 1: span of time, Jupiter could have retained some of that
• 55:12
  Speaker 1: unusual structure. It is a fascinating possibility. But it is
• 55:17
  Speaker 1: only a possibility. You do not need to treat it
• 55:20
  Speaker 1: as an answer. It is simply one path through the mystery,
• 55:24
  Speaker 1: a possible collision, a young Jupiter, a disturbed centre, a
• 55:29
  Speaker 1: core spread outward rather than remaining tightly gathered. And yet,
• 55:34
  Speaker 1: there is another quiet problem. Scientists have tried to recreate
• 55:38
  Speaker 1: such collisions using computer simulations. They can place a young
• 55:43
  Speaker 1: Jupiter into a virtual experiment. They can introduce a large
• 55:47
  Speaker 1: rocky world, They can vary the size and composition of
• 55:51
  Speaker 1: the approaching planet. They can let the two worlds collide
• 55:55
  Speaker 1: inside the computer. And something interesting happens. At first, the
• 56:00
  Speaker 1: simulations can produce something resembling the fuzzy core we see today.
• 56:05
  Speaker 1: The collision can spread the central material outward. The sharp
• 56:09
  Speaker 1: boundary can disappear. The centre becomes diffuse. For a moment,
• 56:14
  Speaker 1: the picture seems to fit. But then the simulation continues.
• 56:18
  Speaker 1: and as time passes, the material tends to settle. The
• 56:22
  Speaker 1: scattered material gradually moves inward. The fuzzy centre begins to
• 56:26
  Speaker 1: become more compact. The core becomes more clearly defined. The
• 56:31
  Speaker 1: computer experiment creates the unusual centre, but then has difficulty
• 56:35
  Speaker 1: keeping it unusual for long enough. And so the mystery remains.
• 56:40
  Speaker 1: The collision idea can explain part of the story. but
• 56:44
  Speaker 1: it does not completely explain the Jupiter you find yourself
• 56:47
  Speaker 1: drifting through now. You can let that uncertainty remain where
• 56:51
  Speaker 1: it is. There is no need to force it into
• 56:54
  Speaker 1: an answer. Science sometimes moves quietly through questions like this.
• 56:59
  Speaker 1: A measurement suggests something unexpected. A model offers one explanation.
• 57:04
  Speaker 1: A simulation tests it. The explanation works for a while,
• 57:09
  Speaker 1: then another detail refuses to fit, and the question remains open.
• 57:14
  Speaker 1: you are still deep inside Jupiter. The metallic hydrogen is
• 57:18
  Speaker 1: around you. The central material is becoming denser. Rock and
• 57:23
  Speaker 1: metal are mixed into a broad region. There is no
• 57:26
  Speaker 1: obvious edge, no simple boundary, no perfect sphere waiting at
• 57:31
  Speaker 1: the centre, just a gradual transition into the deepest part
• 57:35
  Speaker 1: of this enormous planet. And perhaps this is what makes
• 57:38
  Speaker 1: Jupiter so peaceful to imagine. Even at the centre of
• 57:42
  Speaker 1: one of the largest planets in the solar system, there
• 57:45
  Speaker 1: is no requirement that everything be simple. The universe does
• 57:48
  Speaker 1: not need to organise itself into neat layers for you.
• 57:52
  Speaker 1: Sometimes one thing becomes another gradually. Sometimes boundaries blur. Sometimes
• 57:58
  Speaker 1: the answer is not a point, but a region. And sometimes,
• 58:03
  Speaker 1: even after years of observation and careful simulation, a quiet
• 58:07
  Speaker 1: question remains. How did this strange centre get here? You
• 58:12
  Speaker 1: can rest with that question without needing to answer it.
• 58:15
  Speaker 1: Above you, Jupiter continues turning. Around you, the deep interior
• 58:20
  Speaker 1: continues moving. And beneath you, somewhere in the darkness, the
• 58:26
  Speaker 1: oldest material in this enormous planet is still carrying the
• 58:30
  Speaker 1: memory of a history that began billions of years ago.
• 58:34
  Speaker 1: A history that may have started with small pieces gathering together,
• 58:39
  Speaker 1: or perhaps with something much more sudden, and as you
• 58:42
  Speaker 1: drift deeper into that ancient possibility, Jupiter becomes not only
• 58:47
  Speaker 1: a planet to explore, but a quiet record of how
• 58:50
  Speaker 1: worlds can grow, change, collide, and sometimes keep their mysteries
• 58:56
  Speaker 1: for a very long time. You can let yourself drift
• 59:01
  Speaker 1: away from Jupiter's centre now, very slowly. There is no
• 59:06
  Speaker 1: need to hurry back toward the clouds. Instead, Amen. that
• 59:10
  Speaker 1: you are moving backward through time. The Jupiter around you
• 59:14
  Speaker 1: begins to feel younger. The familiar bands of clouds become softer.
• 59:19
  Speaker 1: The enormous storms are not yet turning in the same way.
• 59:23
  Speaker 1: The great liquid interior has not yet settled into the
• 59:26
  Speaker 1: structure you have been exploring. You are looking at Jupiter
• 59:29
  Speaker 1: before it became Jupiter. And somewhere in that ancient darkness
• 59:34
  Speaker 1: is one of the quietest questions in planetary science. How
• 59:38
  Speaker 1: did this enormous world begin? You already know what Jupiter
• 59:42
  Speaker 1: looks like today. A giant planet wrapped in clouds. A
• 59:46
  Speaker 1: world filled with hydrogen. A planet with a deep liquid interior.
• 59:51
  Speaker 1: A region of metallic hydrogen. A powerful magnetic field. and
• 59:57
  Speaker 1: perhaps a broad, diffuse centre rather than a simple, compact core.
• 1:00:02
  Speaker 1: But knowing what Jupiter became does not necessarily tell you
• 1:00:05
  Speaker 1: how it began. To understand that, you have to imagine
• 1:00:09
  Speaker 1: the young solar system. There was once a broad disk
• 1:00:13
  Speaker 1: of material surrounding the young sun. Tiny pieces of rock
• 1:00:17
  Speaker 1: and ice moved through that disk. Dust drifted. Small particles
• 1:00:23
  Speaker 1: met other particles. Some remained apart. Others came together, and gradually,
• 1:00:29
  Speaker 1: in one possible story, small pieces began gathering into larger bodies,
• 1:00:34
  Speaker 1: a little more material, then more, then more again. Over
• 1:00:39
  Speaker 1: very long periods of time, gravity helped these growing objects
• 1:00:43
  Speaker 1: attract additional material. You can imagine the process as something
• 1:00:47
  Speaker 1: almost too slow to watch. A tiny body moves through
• 1:00:51
  Speaker 1: the young solar system. Another piece approaches. They meet. The
• 1:00:56
  Speaker 1: larger object becomes slightly larger. Another piece arrives. The process repeats.
• 1:01:02
  Speaker 1: Nothing dramatic is required. Just time, gravity, and countless small encounters. Eventually,
• 1:01:10
  Speaker 1: one of these growing bodies could become massive enough to
• 1:01:12
  Speaker 1: attract enormous quantities of surrounding gas. And this is where
• 1:01:17
  Speaker 1: Jupiter may have begun to grow very quickly. The young
• 1:01:21
  Speaker 1: planet had already gathered a substantial amount of solid material.
• 1:01:25
  Speaker 1: Then the surrounding hydrogen and helium began falling inward under
• 1:01:29
  Speaker 1: its growing gravity. More gas arrived, then more. The young
• 1:01:34
  Speaker 1: Jupiter became larger, its gravity became stronger, and its ability
• 1:01:39
  Speaker 1: to gather even more material increased. You can imagine the
• 1:01:43
  Speaker 1: process continuing quietly. A growing centre, a growing envelope of gas,
• 1:01:49
  Speaker 1: a world becoming heavier, a world becoming larger. And eventually,
• 1:01:54
  Speaker 1: Something resembling the Jupiter you know today began to emerge.
• 1:01:58
  Speaker 1: This is one broad possibility. A solid seed first, gas afterward.
• 1:02:04
  Speaker 1: But there is another possibility. Perhaps Jupiter did not need
• 1:02:08
  Speaker 1: to build a large solid centre first. Perhaps the young
• 1:02:11
  Speaker 1: solar system contained enormous regions of gas that became unstable
• 1:02:16
  Speaker 1: under their own gravity. Instead of slowly gathering small pieces
• 1:02:20
  Speaker 1: into a solid planet and then collecting gas, A large
• 1:02:24
  Speaker 1: region of gas could have gathered itself directly. The material
• 1:02:28
  Speaker 1: would pull inward, the cloud would become denser, the growing
• 1:02:32
  Speaker 1: concentration would attract more material, and a giant planet could
• 1:02:36
  Speaker 1: form more directly from the surrounding gas. You can imagine
• 1:02:40
  Speaker 1: an enormous cloud slowly drawing itself inward. No single grain
• 1:02:45
  Speaker 1: needs to be the beginning. No small rocky world needs
• 1:02:48
  Speaker 1: to become the seed. The cloud itself begins to gather.
• 1:02:52
  Speaker 1: Gravity quietly pulls everything together, and somewhere within that gathering material,
• 1:02:58
  Speaker 1: a giant planet is born. Both ideas offer a possible
• 1:03:02
  Speaker 1: path toward Jupiter. One begins with solid material and builds upward.
• 1:03:08
  Speaker 1: The other begins with a large gathering of gas. And yet,
• 1:03:12
  Speaker 1: when you return to Jupiter's present-day interior, neither story fits perfectly.
• 1:03:18
  Speaker 1: Because at the centre of Jupiter is You do not
• 1:03:21
  Speaker 1: find exactly what the simplest version of the first story
• 1:03:24
  Speaker 1: might lead you to expect. You do not find an
• 1:03:27
  Speaker 1: obviously compact ball with a clean edge. Instead, you find
• 1:03:31
  Speaker 1: evidence for a broad and diffuse central region. Rock and
• 1:03:35
  Speaker 1: metal appear to extend outward into the surrounding material. The
• 1:03:40
  Speaker 1: centre seems blended, gradual, fuzzy, and that strange structure becomes
• 1:03:45
  Speaker 1: a clue. It tells you that Jupiter's history may have
• 1:03:49
  Speaker 1: been more complicated than the simplest formation pictures suggest. Perhaps
• 1:03:53
  Speaker 1: the young planet experienced a giant collision. Perhaps an enormous
• 1:03:58
  Speaker 1: rocky world once struck it. Perhaps the impact disturbed a
• 1:04:02
  Speaker 1: compact early centre and spread its material outward. Perhaps something
• 1:04:07
  Speaker 1: else happened. The evidence does not yet give you a
• 1:04:10
  Speaker 1: single answer. And this is where it is useful to
• 1:04:14
  Speaker 1: slow down. You do not need to choose between the possibilities.
• 1:04:18
  Speaker 1: You can simply hold them beside each other. A young
• 1:04:21
  Speaker 1: Jupiter slowly gathering solid material. A young Jupiter gathering enormous
• 1:04:26
  Speaker 1: amounts of gas. A young Jupiter forming more directly from
• 1:04:31
  Speaker 1: a collapsing region of the early solar system. And somewhere
• 1:04:34
  Speaker 1: along the way, a strange central region taking shape. The
• 1:04:39
  Speaker 1: water inside Jupiter adds another quiet clue. The spacecraft measurements
• 1:04:44
  Speaker 1: revealed more water in Jupiter's atmosphere than some earlier expectations
• 1:04:48
  Speaker 1: had suggested. That observation became part of the reason scientists
• 1:04:53
  Speaker 1: wanted to look more closely at the planet. The Juno
• 1:04:56
  Speaker 1: spacecraft eventually arrived and began measuring Jupiter from close range.
• 1:05:01
  Speaker 1: It listened to the planet's gravity. It measured its magnetic environment.
• 1:05:06
  Speaker 1: It observed the atmosphere. And these measurements helped reveal that
• 1:05:10
  Speaker 1: Jupiter's interior was not as simple as the older pictures
• 1:05:13
  Speaker 1: had suggested. You can imagine Juno moving above the clouds,
• 1:05:18
  Speaker 1: below it storms, below the storms liquid hydrogen, deeper still
• 1:05:24
  Speaker 1: metallic hydrogen, and far beneath that the broad central region,
• 1:05:30
  Speaker 1: each layer carrying information about the planet's past. Because a
• 1:05:34
  Speaker 1: planet is not only a place, it is also a record,
• 1:05:38
  Speaker 1: Its composition remembers where its material came from. Its interior
• 1:05:43
  Speaker 1: remembers how it grew. Its structure can preserve traces of collisions, gathering, heating,
• 1:05:51
  Speaker 1: and mixing. Jupiter's strange centre may therefore be more than
• 1:05:55
  Speaker 1: an unusual feature. It may be a piece of ancient history,
• 1:05:59
  Speaker 1: a clue left behind billions of years ago. And yet,
• 1:06:04
  Speaker 1: even with spacecraft measurements and computer simulations … the story
• 1:06:08
  Speaker 1: is still incomplete. The giant impact idea can create a
• 1:06:13
  Speaker 1: diffuse centre in simulations, but the material tends to settle
• 1:06:17
  Speaker 1: again over time. The direct collapse idea can explain how
• 1:06:22
  Speaker 1: a giant planet might form without first requiring a large
• 1:06:26
  Speaker 1: solid core, but it does not automatically explain every detail
• 1:06:30
  Speaker 1: of Jupiter's present structure. The traditional gathering story explains how
• 1:06:36
  Speaker 1: a growing solid body might collect gas. But the unusually
• 1:06:40
  Speaker 1: broad central region remains something that needs careful explanation. So
• 1:06:45
  Speaker 1: Jupiter sits quietly between these possibilities. Not quite solved, not
• 1:06:51
  Speaker 1: quite mysterious in every detail, but not completely understood either.
• 1:06:56
  Speaker 1: And perhaps that is a comfortable place to leave the
• 1:06:58
  Speaker 1: question for a while. You do not need every answer
• 1:07:01
  Speaker 1: before you can rest. You can simply imagine the young
• 1:07:05
  Speaker 1: solar system turning slowly around the newborn sun, dust drifting,
• 1:07:11
  Speaker 1: gas moving, small worlds gathering, gravity pulling gently inward, and
• 1:07:17
  Speaker 1: somewhere within that ancient disk, the material that would eventually
• 1:07:21
  Speaker 1: become Jupiter beginning to gather, slowly at first, then more strongly,
• 1:07:28
  Speaker 1: then into something enormous, a planet that would one day
• 1:07:31
  Speaker 1: contain a liquid hydrogen ocean. a vast region of metallic hydrogen,
• 1:07:37
  Speaker 1: powerful electrical currents, enormous storms, and a strange central heart
• 1:07:42
  Speaker 1: without a clear edge. You can let the image become
• 1:07:45
  Speaker 1: distant again. The young solar system fades, the ancient dust
• 1:07:50
  Speaker 1: grows quiet, the growing planet becomes the Jupiter you know,
• 1:07:55
  Speaker 1: and Jupiter continues turning in the darkness, carrying its unfinished
• 1:08:00
  Speaker 1: history inside itself. Perhaps that is the most peaceful thing
• 1:08:04
  Speaker 1: about this enormous world. You can understand more and more
• 1:08:08
  Speaker 1: about it without ever needing to pretend that everything has
• 1:08:10
  Speaker 1: been answered. There are still questions beneath the clouds. There
• 1:08:15
  Speaker 1: are still traces of an ancient beginning. And somewhere in
• 1:08:18
  Speaker 1: the deepest interior, the planet is quietly keeping the story
• 1:08:22
  Speaker 1: of how it became itself. And so, our journey through
• 1:08:28
  Speaker 1: Jupiter can begin to grow quiet. You have drifted beneath
• 1:08:32
  Speaker 1: its clouds, through cold upper layers and distant lightning, past
• 1:08:37
  Speaker 1: the great red spot and into the enormous darkness below.
• 1:08:41
  Speaker 1: You have imagined hydrogen becoming liquid, becoming denser, becoming something
• 1:08:46
  Speaker 1: stranger still, until its tiny electrons could move more freely
• 1:08:51
  Speaker 1: and help carry electricity through the planet. And beneath all
• 1:08:54
  Speaker 1: of that you reached the quiet centre, where Jupiter may
• 1:08:58
  Speaker 1: not have a simple solid heart of all, but a
• 1:09:01
  Speaker 1: broad and gradual region where rock, metal and surrounding material
• 1:09:06
  Speaker 1: slowly blend together. Perhaps Jupiter began by gathering small pieces
• 1:09:11
  Speaker 1: of ancient matter. Perhaps it gathered gas in a different way.
• 1:09:15
  Speaker 1: Perhaps a tremendous collision once changed its young interior. There
• 1:09:19
  Speaker 1: are possibilities, measurements, simulations and questions that remain open. But
• 1:09:24
  Speaker 1: you do not need to carry those questions with you now.
• 1:09:27
  Speaker 1: You can let them become distant. Jupiter will continue turning
• 1:09:31
  Speaker 1: without your attention. Its clouds will continue drifting. The great
• 1:09:35
  Speaker 1: red spot will continue its slow circulation. Deep below, hydrogen
• 1:09:40
  Speaker 1: will continue flowing through immense pressures and temperatures that you
• 1:09:44
  Speaker 1: never need to experience yourself. The magnetic field will continue
• 1:09:49
  Speaker 1: reaching quietly into space. And somewhere in the darkness at
• 1:09:53
  Speaker 1: the centre, the strange diffuse heart of Jupiter will remain
• 1:09:57
  Speaker 1: hidden beneath layer after layer of matter. You are safe.
• 1:10:02
  Speaker 1: There is nothing to do. You do not need to
• 1:10:05
  Speaker 1: remember every detail. You can simply let the images fade,
• 1:10:09
  Speaker 1: one by one. The clouds becoming distant. The lightning becoming faint.
• 1:10:15
  Speaker 1: The red storm becoming smaller. the liquid hydrogen becoming darker,
• 1:10:20
  Speaker 1: the deep interior becoming still. And now, perhaps, you can
• 1:10:24
  Speaker 1: imagine yourself moving gently upward again, not needing to retrace
• 1:10:29
  Speaker 1: every step, simply floating toward the familiar darkness above. There
• 1:10:34
  Speaker 1: is no rush. The universe is not waiting for you.
• 1:10:38
  Speaker 1: Jupiter is not waiting for you. Everything continues perfectly well
• 1:10:43
  Speaker 1: while you rest. And perhaps that is the quiet lesson
• 1:10:47
  Speaker 1: hidden inside this enormous planet. Even something as vast and
• 1:10:51
  Speaker 1: complicated as Jupiter can simply exist, turning slowly through space,
• 1:10:56
  Speaker 1: carrying ancient mysteries inside itself, without needing to explain them tonight.
• 1:11:02
  Speaker 1: So let your breathing become easy. Let your body become heavy.
• 1:11:06
  Speaker 1: Let your thoughts become softer. The stars will remain where
• 1:11:10
  Speaker 1: they are. The planets will continue their slow journeys. And Jupiter,
• 1:11:16
  Speaker 1: enormous and distant, will keep its clouds moving gently beneath
• 1:11:19
  Speaker 1: the sunlight, keeping its strange interior hidden in the darkness.
• 1:11:24
  Speaker 1: You can simply drift. You can rest. And somewhere far away,
• 1:11:29
  Speaker 1: beneath thousands of kilometres of clouds, liquid hydrogen and metallic
• 1:11:34
  Speaker 1: hydrogen continue their quiet motion, while the ancient heart of
• 1:11:38
  Speaker 1: Jupiter keeps a story that the universe has not completely
• 1:11:42
  Speaker 1: told us yet. For now, You can leave that story unfinished.
• 1:11:47
  Speaker 1: You have nothing more to discover tonight. Just listen, and drift,
• 1:11:52
  Speaker 1: and let the darkness become comfortable around you. Good night.