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Venus Is Almost Like Earth... So What Went Wrong_ · 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 explore Venus, the bright and mysterious
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  Speaker 1: world that circles the sun just beyond Earth's orbit, not
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  Speaker 1: to learn everything about it, but simply to notice it, slowly, calmly,
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  Speaker 1: one quiet detail at a time. Before you settle in,
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  Speaker 1: If you truly enjoy these calm journeys through interesting facts
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  Speaker 1: about science, you're welcome to like this video and subscribe,
• 0:36
  Speaker 1: only if it feels right for you. And when you're ready,
• 0:40
  Speaker 1: let me know in the comments where you're listening from,
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  Speaker 1: and what time it is right now. It's always a
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  Speaker 1: quiet joy to imagine how many different places and moments
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  Speaker 1: gather here together. Now, dim the lights. Perhaps let a
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  Speaker 1: fan hum softly somewhere nearby. Allow your breathing to become
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  Speaker 1: comfortable and remember that there is nothing to do, nothing
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  Speaker 1: to solve and nowhere you need to be. You are safe.
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  Speaker 1: Just listen and drift and when you're ready, let your
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  Speaker 1: attention move gently upward toward the evening sky where a
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  Speaker 1: small and distant light is waiting. You can begin with
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  Speaker 1: Venus from very far away, so far away that you
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  Speaker 1: do not need to imagine the heat or the pressure,
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  Speaker 1: or the strange chemistry hidden beneath its clouds. For now,
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  Speaker 1: you only see light. Perhaps it is evening, and the
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  Speaker 1: sun has recently disappeared below the horizon, leaving a soft
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  Speaker 1: fading glow along the edge of the sky. One by one,
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  Speaker 1: the brighter stars begin to appear, and somewhere among them,
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  Speaker 1: lower toward the horizon, you notice something unusually bright. It
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  Speaker 1: does not flicker quite like a distant star. It seems steadier, quieter.
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  Speaker 1: It is Venus, the second planet from the Sun, moving
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  Speaker 1: around our star on a path that carries it closer
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  Speaker 1: to the Sun than Earth. And yet, from where you
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  Speaker 1: are standing, it can become one of the most beautiful
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  Speaker 1: objects in the night sky. Venus travels around the Sun
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  Speaker 1: at an average distance of roughly 108 million kilometres, following
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  Speaker 1: an orbit that is remarkably close to a circle. there
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  Speaker 1: is something peaceful about that. While planets travel through enormous distances,
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  Speaker 1: their paths are not always stretched or dramatically elongated. Venus
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  Speaker 1: follows its route with very little variation, almost as though
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  Speaker 1: it were gently tracing the same invisible circle again and again,
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  Speaker 1: around and around the Sun, through the darkness. And because
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  Speaker 1: Venus moves inside Earth's orbit, it can sometimes come surprisingly
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  Speaker 1: close to you, At its closest approach, Venus can come
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  Speaker 1: to within roughly 41 million kilometres of Earth. 41 million
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  Speaker 1: kilometres is still an almost unimaginable distance. And yet, among
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  Speaker 1: the planets, Venus can become our closest planetary neighbour. You
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  Speaker 1: may look toward that distant point of light and remember
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  Speaker 1: that there is a whole world there, a rocky world.
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  Speaker 1: A world with mountains, plains, clouds, volcanoes, and a sky
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  Speaker 1: of its own. And in a broad physical sense, Venus
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  Speaker 1: is remarkably familiar. Its size is close to Earth's. Its
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  Speaker 1: mass is similar. Its density is similar, and if you
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  Speaker 1: could somehow stand on its surface, the pull of gravity
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  Speaker 1: beneath your feet would feel surprisingly close to what you
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  Speaker 1: know here on Earth. Venus is slightly smaller than Earth.
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  Speaker 1: measuring about 12,000 kilometres across, and its surface gravity is
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  Speaker 1: roughly 9 tenths of Earth's. This is why Venus is
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  Speaker 1: sometimes called Earth's sister planet. From a distance, the resemblance
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  Speaker 1: can feel almost comforting. Two rocky worlds, two neighbouring planets,
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  Speaker 1: two places made from many of the same basic ingredients
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  Speaker 1: of the early solar system. But the resemblance becomes more
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  Speaker 1: complicated when you begin to look at Venus in the
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  Speaker 1: evening sky. Because Venus has a curious relationship with sunlight,
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  Speaker 1: you might imagine that the planet should be brightest when
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  Speaker 1: it is closest to Earth, but that is not quite
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  Speaker 1: how it works. When Venus comes especially close to you,
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  Speaker 1: it is positioned between Earth and the Sun, which means
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  Speaker 1: that the side facing Earth is mostly the dark side
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  Speaker 1: of the planet. You are looking toward the part of
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  Speaker 1: Venus where night has fallen, and so, Strangely, the closest
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  Speaker 1: Venus is not necessarily the brightest Venus. Instead, the planet
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  Speaker 1: can become extraordinarily bright when it appears as a thin crescent,
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  Speaker 1: when only a narrow portion of its cloud-covered surface is
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  Speaker 1: illuminated from our perspective. The result is a delicate shape
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  Speaker 1: of light suspended against the darkness. And because Venus is
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  Speaker 1: wrapped in bright, reflective clouds, that small crescent can shine
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  Speaker 1: with remarkable intensity. Venus is so bright that people have
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  Speaker 1: sometimes mistaken it for something much stranger. Across history, people
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  Speaker 1: looking toward the sky without knowing what they were seeing
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  Speaker 1: have reported unusual lights, mysterious objects, and things that seem
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  Speaker 1: to move or hover where no ordinary star should be. Sometimes,
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  Speaker 1: the explanation was simply Venus, a distant planet. a world
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  Speaker 1: that had been there all along. And if you happen
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  Speaker 1: to see Venus as a thin crescent through a telescope,
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  Speaker 1: the sight can be strangely delicate. It is difficult to
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  Speaker 1: connect that soft little curve of light with the world
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  Speaker 1: that exists beneath it. You see only sunlight reflected from clouds.
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  Speaker 1: You do not see the enormous pressure waiting below. You
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  Speaker 1: do not see the heat. You do not see the
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  Speaker 1: ancient volcanic planes. you see a small, quiet crescent. And
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  Speaker 1: perhaps that is part of what makes Venus so interesting.
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  Speaker 1: It does not look dangerous, it looks peaceful. There is
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  Speaker 1: another rare moment when Earth and Venus can briefly line
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  Speaker 1: up in a particularly beautiful way. Sometimes, Venus passes directly
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  Speaker 1: across the face of the Sun, as seen from Earth.
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  Speaker 1: This is called a transit. But it is an unusually
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  Speaker 1: rare event. Transits of Venus tend to arrive in pairs,
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  Speaker 1: with two appearances separated by about eight years, and then
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  Speaker 1: a very long silence follows, often lasting more than a
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  Speaker 1: century before another pair occurs. The rarity comes from the
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  Speaker 1: fact that Venus and Earth travel around the Sun on
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  Speaker 1: slightly different orbital planes. They do not normally line up perfectly,
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  Speaker 1: and Venus also needs roughly 584 Earth days to catch
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  Speaker 1: up with Earth again in its repeating relationship with our planet.
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  Speaker 1: So the geometry has to be just right. The planets
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  Speaker 1: continue moving, the Sun continues shining, Earth continues turning, and
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  Speaker 1: only once in a very long while does Venus cross
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  Speaker 1: the face of the Sun from our particular viewpoint. It
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  Speaker 1: is a quiet reminder that even in a solar system
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  Speaker 1: filled with motion, some alignments are extraordinarily patient. You may
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  Speaker 1: never see one yourself, And that is perfectly all right.
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  Speaker 1: You can simply imagine it, a small dark circle moving
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  Speaker 1: slowly across the enormous face of the sun, a world
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  Speaker 1: passing between worlds. And all of this is Venus from
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  Speaker 1: a distance, bright, quiet, almost familiar, a planet close enough
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  Speaker 1: to Earth to be called our sister, yet distant enough
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  Speaker 1: to remain mysterious. For now, you are still looking at
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  Speaker 1: it from far away. You have not entered its atmosphere.
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  Speaker 1: You have not felt its gravity. You have not descended
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  Speaker 1: through its clouds. You are simply watching that small light
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  Speaker 1: resting in the evening darkness. And perhaps, for a moment,
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  Speaker 1: it is enough to let Venus remain exactly as it
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  Speaker 1: appears from here, beautiful and still, turning somewhere beyond the
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  Speaker 1: quiet sky. Because beneath that peaceful light, Venus is moving
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  Speaker 1: in a very unusual way, turning so slowly that and
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  Speaker 1: in such a different direction that even the meaning of
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  Speaker 1: a day begins to change. As you remain there beneath
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  Speaker 1: the evening sky, Venus continues to shine quietly in the distance.
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  Speaker 1: You cannot see it turning, you cannot see the enormous
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  Speaker 1: journey it is making around the sun. And yet, beneath
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  Speaker 1: that small point of light, an entire planet is slowly
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  Speaker 1: moving through space. Very slowly. In fact, Venus turns more
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  Speaker 1: slowly than any other planet in the solar system. If
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  Speaker 1: you could somehow watch Venus from far above its clouds
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  Speaker 1: and patiently wait for the planet to complete one full turn,
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  Speaker 1: you would have to wait for about 243 Earth days.
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  Speaker 1: 243 days for one rotation. That is longer than the
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  Speaker 1: time Venus needs to travel once around the Sun. Its
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  Speaker 1: year lasts about 225 Earth days. So there is something
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  Speaker 1: rather strange about Venus. The planet can complete a journey
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  Speaker 1: around the Sun before it has finished turning once around
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  Speaker 1: its own axis. You can let that idea settle for
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  Speaker 1: a moment. A year passes, the seasons of Earth come
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  Speaker 1: and go, the Moon changes through many phases, and Venus
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  Speaker 1: is still slowly turning. But even this is not the
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  Speaker 1: strangest part. Venus does not turn in the same direction
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  Speaker 1: as most of the other planets. The planets travel around
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  Speaker 1: the Sun in the same general direction, moving together through
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  Speaker 1: the vastness of the solar system. But when Venus turns
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  Speaker 1: on its own axis, it turns the opposite way. From
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  Speaker 1: the perspective of its rotation, the planet is moving backward.
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  Speaker 1: Scientists call this retrograde rotation, but you do not need
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  Speaker 1: to remember the name. You can simply imagine a world
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  Speaker 1: turning slowly in the opposite direction from what you might expect.
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  Speaker 1: If you were standing somewhere on its surface, the experience
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  Speaker 1: would be very different from standing on Earth. The sun
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  Speaker 1: would still appear to move across the sky, but the
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  Speaker 1: rhythm would be extraordinarily slow. One sunrise would arrive, and
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  Speaker 1: then the daylight would linger for a very long time.
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  Speaker 1: The light would gradually shift. The shadows would slowly change.
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  Speaker 1: And eventually, after many weeks and many more weeks, the
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  Speaker 1: sun would complete its long journey across the sky. Because
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  Speaker 1: Venus turns backward, the time from one sunrise to the
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  Speaker 1: next is actually shorter than the time it takes the
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  Speaker 1: planet to make one full rotation relative to the distant stars.
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  Speaker 1: This sunrise-to-sunrise cycle lasts about 117 Earth days. So while
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  Speaker 1: Venus takes about 225 days to travel once around the Sun,
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  Speaker 1: you would experience fewer than two complete sunrise-to-sunrise days during
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  Speaker 1: that entire Venusian year. It is difficult to imagine time
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  Speaker 1: moving that slowly. On Earth, a day can seem long
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  Speaker 1: when you are tired. A night can feel long when
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  Speaker 1: you are waiting for morning. But on Venus... The passage
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  Speaker 1: from one sunrise to another unfolds on a completely different scale.
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  Speaker 1: The light would move almost imperceptibly, the planet would continue
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  Speaker 1: turning beneath your feet, and the sky would seem to
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  Speaker 1: have all the time in the universe. There is also
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  Speaker 1: another way to appreciate just how slowly Venus turns. At
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  Speaker 1: its equator, the surface moves at only about 6.5 km
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  Speaker 1: per hour because of the planet's rotation. That is slower
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  Speaker 1: than a gentle bicycle ride. For a planet, it is
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  Speaker 1: remarkably slow, and this slow turning has another subtle consequence.
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  Speaker 1: Venus is almost perfectly round. A rapidly spinning world tends
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  Speaker 1: to bulge slightly around its middle, like a soft ball
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  Speaker 1: that has been gently stretched outward by rotation. Venus spins
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  Speaker 1: so slowly that this effect is very small. It is
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  Speaker 1: one of the most nearly spherical planetary bodies in the
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  Speaker 1: solar system, so even the shape of Venus carries the
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  Speaker 1: quiet imprint of its unusual motion, a world that turns
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  Speaker 1: so slowly that its rotation barely disturbs its roundness. And yet,
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  Speaker 1: Venus did not necessarily begin its life turning this way.
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  Speaker 1: We do not know exactly why it rotates backward. There
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  Speaker 1: are several possibilities. Long ago, when the solar system was young,
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  Speaker 1: Venus may have experienced a tremendous collision with another large body.
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  Speaker 1: An impact of enormous scale could have altered the direction
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  Speaker 1: in which the planet was turning. There are also possibilities
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  Speaker 1: involving the slow gravitational pull of the Sun over immense
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  Speaker 1: stretches of time. And Venus has something else that Earth
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  Speaker 1: does not have in quite the same way, a massive,
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  Speaker 1: dense atmosphere surrounding the planet. The movement of that atmosphere
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  Speaker 1: may also have played a role in gradually changing the
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  Speaker 1: planet's rotation. Perhaps no single explanation tells the entire story.
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  Speaker 1: Perhaps Venus's strange rotation is the result of several very
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  Speaker 1: slow influences, acting together over billions of years. You do
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  Speaker 1: not need to choose between them tonight. You can simply
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  Speaker 1: let the mystery remain where it is. Somewhere in the
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  Speaker 1: deep past, Venus became a world that turns backward. And
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  Speaker 1: now it continues that slow motion, year after year, century
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  Speaker 1: after century, almost without hurry. There is something soothing about
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  Speaker 1: planetary time. Nothing needs to happen quickly. A planet does
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  Speaker 1: not need to rush. Venus can take hundreds of days
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  Speaker 1: to turn. Its clouds can travel around it in their
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  Speaker 1: own rhythm. Its surface can remain beneath those clouds for
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  Speaker 1: millions of years. And from far away, You simply see
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  Speaker 1: the result as a quiet point of light. Perhaps this
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  Speaker 1: is one of the easiest things to forget when looking
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  Speaker 1: at a planet. A planet that seems still is never
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  Speaker 1: really still. Venus is turning. Venus is orbiting. Its clouds
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  Speaker 1: are moving. Its atmosphere is shifting. Its surface is slowly changing.
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  Speaker 1: And all of this happens so gradually that from Earth,
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  Speaker 1: the planet appears almost motionless. there is no urgency in
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  Speaker 1: any of it. You can simply imagine Venus continuing its
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  Speaker 1: slow backward turn, carrying its mountains and plains through the
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  Speaker 1: long darkness, while the sun waits patiently ahead of it.
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  Speaker 1: And as you drift closer, another resemblance to Earth begins
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  Speaker 1: to appear. For all its strange motion, Venus is not
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  Speaker 1: a tiny, distant world unlike anything you know. In size,
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  Speaker 1: weight and gravity, it is surprisingly familiar, It is almost
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  Speaker 1: as though Earth and Venus were shaped from the same
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  Speaker 1: quiet piece of cosmic material, and then, somewhere along the way,
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  Speaker 1: began taking very different paths, and that difference becomes much
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  Speaker 1: easier to feel when you imagine yourself standing on the surface.
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  Speaker 1: As Venus continues its slow backward turning, you can begin
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  Speaker 1: to move a little closer. The bright point in the
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  Speaker 1: evening sky becomes a world. And the first thing you
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  Speaker 1: notice is how familiar it seems. Not familiar in its clouds,
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  Speaker 1: not yet, and certainly not in the heat waiting below them,
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  Speaker 1: but familiar in its basic shape and size. Venus is
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  Speaker 1: a rocky planet, like Earth. It belongs to the same
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  Speaker 1: small family of worlds that formed relatively close to the sun,
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  Speaker 1: worlds made mostly of rock and metal. worlds with solid
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  Speaker 1: surfaces beneath their atmospheres. And Venus is surprisingly close to
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  Speaker 1: Earth in size. Its diameter is about 12,000 kilometres, only
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  Speaker 1: a little smaller than Earth's. Its density is also quite similar.
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  Speaker 1: Its mass is similar. And perhaps most quietly surprising of all,
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  Speaker 1: its gravity is close to what you already know. If
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  Speaker 1: you could somehow stand on Venus without being overwhelmed by
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  Speaker 1: everything else around you, Your body would not feel dramatically lighter.
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  Speaker 1: The ground would still hold you with a familiar strength.
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  Speaker 1: Your feet would still feel firmly connected to the surface.
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  Speaker 1: You would not suddenly float away. In that narrow sense,
• 17:16
  Speaker 1: Venus might feel like a distant sister to Earth. Two
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  Speaker 1: rocky worlds, not identical, but close enough that their resemblance
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  Speaker 1: is difficult to ignore. You can imagine placing the two
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  Speaker 1: planets beside one another in the darkness. Earth, blue beneath
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  Speaker 1: its clouds. Venus, pale and golden beneath its clouds. Similar
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  Speaker 1: in size, similar in gravity, both circling the same sun.
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  Speaker 1: Both formed from the material that surrounded the young star
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  Speaker 1: billions of years ago. And yet, if you continue your
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  Speaker 1: descent toward Venus, the resemblance begins to fade. At first,
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  Speaker 1: you are still high above the surface. The clouds stretch
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  Speaker 1: around you, hiding what lies below. But as you descend,
• 18:02
  Speaker 1: the atmosphere becomes thicker and thicker and thicker still. On Earth,
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  Speaker 1: the atmosphere above you is almost weightless compared with the
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  Speaker 1: solid ground beneath your feet. You rarely notice it pressing
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  Speaker 1: on you. The air is simply there, a quiet mixture
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  Speaker 1: surrounding you, moving gently through forests, across oceans and around mountains.
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  Speaker 1: On Venus, the atmosphere is something much more substantial. It
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  Speaker 1: is not merely a thin layer surrounding the planet. It
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  Speaker 1: is an enormous, dense ocean of gas. The pressure at
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  Speaker 1: the surface is roughly 92 times greater than the pressure
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  Speaker 1: at sea level on Earth. You can think of it
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  Speaker 1: as the kind of pressure you would experience far beneath
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  Speaker 1: the surface of Earth's oceans, close to a kilometre down.
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  Speaker 1: Not because Venus is covered by an ocean of water.
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  Speaker 1: There is no ocean waiting beneath your feet. Instead, the
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  Speaker 1: ocean is made of atmosphere. A deep, invisible mass of
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  Speaker 1: gas pressing downward from above and pressing around you from
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  Speaker 1: every direction. The atmosphere itself is extraordinarily dense. It is
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  Speaker 1: roughly 93 times as dense as the atmosphere around you
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  Speaker 1: on Earth. And because Venus is slightly smaller than Earth
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  Speaker 1: while holding such a massive atmosphere, the air becomes packed
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  Speaker 1: tightly around the planet. The familiar sister begins to feel
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  Speaker 1: less familiar. You can imagine descending through the clouds, slowly,
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  Speaker 1: without hurry. Above you, the bright cloud layer becomes distant.
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  Speaker 1: Below you, the surface begins to emerge from the haze.
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  Speaker 1: The light is muted, the air feels heavy, and although
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  Speaker 1: the gravity beneath you still feels surprisingly familiar, almost everything
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  Speaker 1: else has changed. This is where the great similarity between
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  Speaker 1: Earth and Venus begins to become a strange kind of contrast.
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  Speaker 1: The two planets may resemble one another in their size
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  Speaker 1: and structure, but a planet is not defined only by
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  Speaker 1: the rock beneath its surface. The atmosphere matters, the amount
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  Speaker 1: of air matters. The chemistry of that air matters, and
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  Speaker 1: perhaps most importantly, the way that atmosphere interacts with sunlight matters.
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  Speaker 1: Venus is wrapped in an atmosphere dominated by carbon dioxide.
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  Speaker 1: You do not need to picture individual molecules. You can
• 20:25
  Speaker 1: simply imagine an enormous invisible sea surrounding the planet, filled
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  Speaker 1: with a gas that allows sunlight to enter, but makes
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  Speaker 1: it much harder for heat to escape. Sunlight arrives from above.
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  Speaker 1: It passes through the clouds. Some of that energy reaches
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  Speaker 1: the surface. The surface warms. And then, as the warm
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  Speaker 1: ground tries to release that energy back towards space, the
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  Speaker 1: thick atmosphere holds much of it close to the planet.
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  Speaker 1: The warmth remains. Then more sunlight arrives. More warmth is stored.
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  Speaker 1: More heat tries to leave. And again, much of it remains.
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  Speaker 1: There is no single dramatic moment. No sudden flash. no
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  Speaker 1: sharp boundary between one Venus and another. Instead, you can
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  Speaker 1: imagine the planet slowly settling into a different thermal rhythm,
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  Speaker 1: one in which heat becomes difficult to let go of.
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  Speaker 1: This is the extreme greenhouse effect. But you do not
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  Speaker 1: need to think of it as a complicated equation. Think
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  Speaker 1: instead of a world wrapped in an atmosphere that is
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  Speaker 1: extraordinarily reluctant to release its warmth. And now the bright
• 21:35
  Speaker 1: planet you saw earlier begins to look very different. From Earth,
• 21:41
  Speaker 1: Venus appears almost gentle. Its clouds reflect sunlight. Its surface
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  Speaker 1: remains hidden. It shines beautifully in the evening sky. But
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  Speaker 1: beneath those clouds, the atmosphere is heavy enough to press
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  Speaker 1: with enormous force, and dense enough to hold heat with
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  Speaker 1: extraordinary efficiency. You can remain above the surface for a moment.
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  Speaker 1: There is no need to go all the way down yet.
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  Speaker 1: just float quietly among the upper layers of the atmosphere,
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  Speaker 1: looking downward through the pale haze. The planet below is
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  Speaker 1: still a rocky world, still similar in size to Earth,
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  Speaker 1: still held together by the same basic forces of nature,
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  Speaker 1: and yet, somehow, it has become a place where the
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  Speaker 1: air itself feels almost like an ocean. Perhaps this is
• 22:28
  Speaker 1: one of the most interesting things about Venus. Its strangeness
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  Speaker 1: does not begin with some completely alien material. It begins
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  Speaker 1: with familiar things. Rock, air, sunlight, heat, gravity. The same
• 22:42
  Speaker 1: broad ingredients that make Earth what it is. Only here,
• 22:47
  Speaker 1: they have been arranged differently. And as you drift a
• 22:50
  Speaker 1: little lower, toward the deeper atmosphere, the temperature begins to
• 22:55
  Speaker 1: tell you just how different that arrangement has become. The
• 22:58
  Speaker 1: warmth is no longer something you can imagine as distant sunlight.
• 23:03
  Speaker 1: It is becoming part of the world itself. And beneath
• 23:07
  Speaker 1: the pale clouds, Venus is holding on to that warmth very,
• 23:11
  Speaker 1: very carefully. You are drifting lower now, slowly, gently, through
• 23:19
  Speaker 1: the pale atmosphere of Venus. Above you, the clouds stretch
• 23:23
  Speaker 1: outward in every direction. Below you, the surface is still hidden.
• 23:28
  Speaker 1: There is no need to hurry. You can simply remain
• 23:31
  Speaker 1: here for a while. Suspended between the distant sunlight above
• 23:35
  Speaker 1: and the warm, rocky world below. From this height, Venus
• 23:39
  Speaker 1: may still look peaceful. Its clouds are bright. Its atmosphere
• 23:44
  Speaker 1: is almost luminous. And yet, somewhere beneath you, the temperature
• 23:48
  Speaker 1: is rising. Very slowly at first. Then more noticeably. The
• 23:53
  Speaker 1: warmth is becoming part of everything around you. Venus receives
• 23:58
  Speaker 1: sunlight from the same star that warms Earth. But the
• 24:01
  Speaker 1: story of that sunlight is very different here. The atmosphere
• 24:05
  Speaker 1: of Venus is dominated by carbon dioxide, a gas that
• 24:10
  Speaker 1: plays an important role in holding heat close to the planet.
• 24:14
  Speaker 1: Sunlight travels through the upper atmosphere. Some of it is
• 24:18
  Speaker 1: reflected away by the clouds. Some passes downward. The surface
• 24:23
  Speaker 1: absorbs energy and becomes warm. And then the surface begins
• 24:28
  Speaker 1: to release that warmth again. but the heat does not
• 24:31
  Speaker 1: simply disappear into space. The thick atmosphere absorbs and redirects
• 24:36
  Speaker 1: much of the energy, allowing the warmth to remain close
• 24:39
  Speaker 1: to the surface. Then the process continues. Sunlight arrives. The
• 24:44
  Speaker 1: surface warms. Heat rises. The atmosphere holds much of it,
• 24:50
  Speaker 1: and the warmth remains. You can imagine this happening not
• 24:53
  Speaker 1: as one dramatic event, but as an extremely slow exchange,
• 24:57
  Speaker 1: repeated over and over again, for an almost unimaginable length
• 25:02
  Speaker 1: of time. Venus becomes a world where heat has very
• 25:06
  Speaker 1: little desire to leave. This is the extreme greenhouse effect,
• 25:11
  Speaker 1: and it is one of the most important reasons Venus
• 25:14
  Speaker 1: is the hottest planet in the solar system. There is
• 25:17
  Speaker 1: something especially interesting about that. Mercury is closer to the Sun,
• 25:22
  Speaker 1: much closer, yet Venus is hotter. Mercury receives far more
• 25:27
  Speaker 1: direct sunlight, but it has almost no atmosphere to hold
• 25:31
  Speaker 1: that energy close to its surface. Venus, by contrast, has
• 25:35
  Speaker 1: built an enormous atmospheric reservoir for heat. So even though
• 25:40
  Speaker 1: less sunlight reaches Venus than Mercury, the warmth that does
• 25:43
  Speaker 1: arrive is held extraordinarily well. It is as though the
• 25:47
  Speaker 1: planet has learned how to keep the sunlight long after
• 25:50
  Speaker 1: the original light has disappeared. And this means that night
• 25:54
  Speaker 1: on Venus does not bring the kind of relief you
• 25:56
  Speaker 1: might expect. On Earth, When the sun goes down, the
• 26:01
  Speaker 1: surface begins to cool. The darkness allows heat to escape.
• 26:05
  Speaker 1: The temperature can fall. But on Venus, the dense atmosphere
• 26:09
  Speaker 1: keeps the warmth moving around the planet. The night remains
• 26:13
  Speaker 1: extremely hot. Even the polar regions remain remarkably warm. There
• 26:18
  Speaker 1: is no comfortable cold corner waiting far from the sun.
• 26:22
  Speaker 1: The atmosphere has spread the warmth so effectively that the
• 26:25
  Speaker 1: entire planet participates in the same slow, enclosed thermal environment.
• 26:32
  Speaker 1: You can imagine the sun disappearing below the horizon. The
• 26:36
  Speaker 1: sky darkens. But the ground beneath you remains intensely hot.
• 26:41
  Speaker 1: The darkness changes the light, but it barely changes the heat.
• 26:46
  Speaker 1: And this is one of the quietest strange things about Venus.
• 26:50
  Speaker 1: On Earth, night feels like a release. On Venus, Night
• 26:54
  Speaker 1: is simply another shade of the same heat. The average
• 26:58
  Speaker 1: surface temperature is around 460 degrees Celsius. You do not
• 27:03
  Speaker 1: need to hold on to the number. Instead, imagine a
• 27:06
  Speaker 1: rocky landscape where temperatures are high enough to make the
• 27:09
  Speaker 1: surface itself an environment of extreme heat. There is no
• 27:14
  Speaker 1: cool evening waiting for you, no gentle dawn after a
• 27:18
  Speaker 1: freezing night. Only a world that remains hot, almost continuously,
• 27:24
  Speaker 1: beneath its thick atmospheric blanket, and the seasons do not
• 27:27
  Speaker 1: provide much relief either. Venus is tilted only very slightly
• 27:32
  Speaker 1: as it travels around the Sun, so the changes that
• 27:35
  Speaker 1: would normally create strong seasons are quite small. Earth leans
• 27:39
  Speaker 1: enough for sunlight to shift between hemispheres over the course
• 27:42
  Speaker 1: of a year. Summer arrives. Winter follows. Spring and autumn
• 27:47
  Speaker 1: pass between them. Venus does not experience this kind of
• 27:51
  Speaker 1: strong seasonal rhythm. Its year passes quietly, the planet circles
• 27:57
  Speaker 1: the sun, the clouds continue to move, and the surface
• 28:01
  Speaker 1: remains hot. There is something almost hypnotic about that consistency.
• 28:06
  Speaker 1: Imagine standing in a place where the difference between day
• 28:09
  Speaker 1: and night is barely meaningful for temperature, where the poles
• 28:13
  Speaker 1: are not dramatically cooler than the rest of the planet,
• 28:17
  Speaker 1: and where the atmosphere continually moves warmth from one region
• 28:20
  Speaker 1: to another. The planet is turning very slowly, but its
• 28:25
  Speaker 1: heat is not staying in one place. It is being
• 28:28
  Speaker 1: carried through the atmosphere, passed from one region to another, held, redistributed,
• 28:34
  Speaker 1: held again. And high above you, the clouds are doing
• 28:38
  Speaker 1: something even more unusual. They are made partly from sulphur
• 28:42
  Speaker 1: dioxide and tiny droplets of sulphuric acid. These droplets are
• 28:47
  Speaker 1: highly corrosive. From a distance, The clouds appear soft and bright,
• 28:53
  Speaker 1: almost like a pale blanket wrapped around the planet. But
• 28:57
  Speaker 1: the appearance is deceptive. The clouds are not made from
• 29:01
  Speaker 1: the gentle water droplets that form most familiar clouds on Earth.
• 29:05
  Speaker 1: They belong to a very different chemical environment. Tiny acidic
• 29:09
  Speaker 1: droplets drift through the atmosphere. Some can fall downward as
• 29:14
  Speaker 1: acid rain. But Venus is so hot near the surface
• 29:18
  Speaker 1: that that the droplets evaporate before reaching the ground. So
• 29:22
  Speaker 1: even the rain does not quite complete its journey. It
• 29:26
  Speaker 1: begins high in the atmosphere. It falls. And somewhere above
• 29:30
  Speaker 1: the surface, the heat takes it away again. Everything seems
• 29:34
  Speaker 1: caught in a cycle. Sunlight arrives. Heat remains. Clouds move.
• 29:39
  Speaker 1: droplets fall, heat turns them back into vapour, and the
• 29:43
  Speaker 1: atmosphere continues its slow circulation around the planet. You can
• 29:48
  Speaker 1: simply listen to that rhythm in your imagination. Nothing sudden,
• 29:52
  Speaker 1: nothing sharp, just a world endlessly exchanging light, heat and motion.
• 29:58
  Speaker 1: From Earth, Venus looks bright because its clouds reflect so
• 30:02
  Speaker 1: much sunlight back into space. But those same clouds also
• 30:06
  Speaker 1: help hide the world below. They form a luminous ceiling
• 30:10
  Speaker 1: between you and the surface, and as you drift beneath them,
• 30:14
  Speaker 1: you begin to understand the strange contradiction of Venus. The
• 30:18
  Speaker 1: planet looks bright from far away, yet beneath the brightness,
• 30:22
  Speaker 1: heat is being held close. The planet looks soft, yet
• 30:26
  Speaker 1: its clouds contain acid. The planet looks calm, yet its
• 30:31
  Speaker 1: atmosphere is moving continuously around the world, and perhaps the
• 30:35
  Speaker 1: strangest part is still waiting above you, because while Venus
• 30:38
  Speaker 1: itself turns so slowly that a single rotation takes longer
• 30:43
  Speaker 1: than its year, the clouds surrounding it move much faster.
• 30:47
  Speaker 1: The planet barely turns, but the sky is already beginning
• 30:51
  Speaker 1: to race. You are still somewhere above the surface of Venus,
• 30:58
  Speaker 1: surrounded by the pale clouds that hide the world below.
• 31:02
  Speaker 1: The planet beneath you is turning very slowly. You already
• 31:06
  Speaker 1: know this. Its enormous body takes more than 200 Earth
• 31:10
  Speaker 1: days to complete one rotation. From the surface, the movement
• 31:14
  Speaker 1: would be almost impossible to notice. But now, as you
• 31:18
  Speaker 1: remain suspended in the atmosphere, you begin to notice something
• 31:22
  Speaker 1: very different. the sky is moving. And it is moving
• 31:26
  Speaker 1: much faster than the planet beneath it. High above the surface,
• 31:31
  Speaker 1: the winds can become extraordinarily fast. At the tops of
• 31:35
  Speaker 1: the clouds, they can reach roughly 300 kilometres per hour,
• 31:39
  Speaker 1: carrying the clouds around the planet in only about four
• 31:43
  Speaker 1: or five Earth days. So Venus has a strange rhythm.
• 31:48
  Speaker 1: The solid planet turns slowly. The atmosphere moves quickly. The
• 31:53
  Speaker 1: ground beneath you seems almost still, while the sky above
• 31:57
  Speaker 1: you quietly races around the world. Scientists have a name
• 32:01
  Speaker 1: for this unusual atmospheric motion. They call it super-rotation. But
• 32:06
  Speaker 1: you do not need to remember the word. You can
• 32:09
  Speaker 1: simply imagine the clouds flowing around Venus, again and again,
• 32:14
  Speaker 1: moving far more quickly than the rocky planet beneath them.
• 32:18
  Speaker 1: It is almost as though the atmosphere has found its
• 32:20
  Speaker 1: own clock. The planet keeps one slow rhythm, the clouds
• 32:25
  Speaker 1: keep another, and somewhere between them, the sunlight continues to
• 32:29
  Speaker 1: move through the pale sky. If you were near the surface,
• 32:33
  Speaker 1: the wind itself would not necessarily feel like a hurricane.
• 32:38
  Speaker 1: The winds close to the ground are relatively gentle, often
• 32:42
  Speaker 1: only a few kilometres per hour, but the atmosphere of
• 32:45
  Speaker 1: Venus is so dense that even these modest movements of
• 32:48
  Speaker 1: air can exert considerable force. A small rock or a
• 32:53
  Speaker 1: little piece of dust does not need to be pushed
• 32:56
  Speaker 1: by a violent storm to move. The thick air can
• 32:59
  Speaker 1: gradually nudge it across the ground. Very slowly, almost patiently,
• 33:04
  Speaker 1: a grain of dust moves. A small stone shifts. The
• 33:09
  Speaker 1: atmosphere continues passing over the surface, and high above, the
• 33:13
  Speaker 1: clouds are moving much faster. You can imagine looking upward
• 33:17
  Speaker 1: from that quiet landscape. You would not see blue, you
• 33:21
  Speaker 1: would see layers of pale, thick atmosphere. The clouds cover
• 33:25
  Speaker 1: Venus so completely that the surface remains hidden from ordinary
• 33:28
  Speaker 1: views from space. They reflect much of the sunlight that
• 33:32
  Speaker 1: reaches them. Only a small portion of the incoming sunlight
• 33:36
  Speaker 1: makes its way through the cloud layers toward the lower
• 33:39
  Speaker 1: atmosphere and surface. This gives Venus its remarkable brightness from Earth.
• 33:44
  Speaker 1: The same clouds that hide the planet also help make
• 33:48
  Speaker 1: it shine. There is another quiet contradiction here. The clouds
• 33:52
  Speaker 1: are bright enough to make Venus one of the most
• 33:54
  Speaker 1: noticeable objects in our sky. Yet beneath them, very little
• 33:59
  Speaker 1: of the sunlight reaches the ground directly. And still, the
• 34:04
  Speaker 1: ground remains extraordinarily hot. The reason is waiting in the
• 34:08
  Speaker 1: thick atmosphere below. Heat does not need direct sunlight at
• 34:13
  Speaker 1: the surface to remain. It can be held and redistributed
• 34:17
  Speaker 1: by the atmosphere, circulating slowly through the dense air. So
• 34:22
  Speaker 1: the bright world you see from Earth and the furnace
• 34:25
  Speaker 1: beneath the clouds are really parts of the same system.
• 34:29
  Speaker 1: The clouds above are reflective, the atmosphere below is heat-trapping,
• 34:34
  Speaker 1: and together they create the unusual appearance of Venus. You
• 34:38
  Speaker 1: can remain among those clouds for a while. Tiny droplets
• 34:42
  Speaker 1: drift around you. They are not made from ordinary water.
• 34:46
  Speaker 1: Many contain sulfuric acid, a highly corrosive substance. From far away,
• 34:53
  Speaker 1: the clouds look soft. Up close, they are chemically harsh.
• 34:58
  Speaker 1: The droplets can fall downward, becoming something like acid rain.
• 35:02
  Speaker 1: But as they descend into the hotter regions of the atmosphere,
• 35:06
  Speaker 1: much of that rain evaporates before it reaches the surface.
• 35:10
  Speaker 1: So the rain begins its journey above you, it falls
• 35:13
  Speaker 1: through the atmosphere, and then Somewhere along the way, the
• 35:17
  Speaker 1: intense heat takes it back into the air. Nothing reaches
• 35:21
  Speaker 1: the ground quite as easily as you might expect. Even
• 35:24
  Speaker 1: rainfall has to pass through Venus's heat. And the atmosphere
• 35:28
  Speaker 1: continues to move. There are also signs that Venus can
• 35:32
  Speaker 1: produce lightning, although it appears to be less common than
• 35:35
  Speaker 1: lightning on Earth. Electrical activity can arise within the clouds.
• 35:40
  Speaker 1: adding another quiet movement to a world that seems so
• 35:43
  Speaker 1: still when viewed from a distance. You might imagine a
• 35:47
  Speaker 1: flash occurring somewhere far away, hidden inside the pale atmosphere.
• 35:52
  Speaker 1: You would not necessarily see the landscape below. You would
• 35:55
  Speaker 1: simply know that somewhere within the clouds, electricity has briefly
• 36:00
  Speaker 1: moved through the sky, and then everything becomes quiet again.
• 36:05
  Speaker 1: There is also an enormous swirling structure near the southern
• 36:08
  Speaker 1: polar region, High above the surface, near the cloud tops,
• 36:13
  Speaker 1: the atmosphere forms a large vortex, a broad region of
• 36:17
  Speaker 1: air moving in a slow, organised pattern. It is not
• 36:22
  Speaker 1: a small storm, it is a structure on a planetary scale.
• 36:26
  Speaker 1: You can imagine yourself drifting above it, looking down into
• 36:30
  Speaker 1: layers of moving clouds, watching patterns that change gradually as
• 36:35
  Speaker 1: the atmosphere circles beneath you. The vortex is one more
• 36:39
  Speaker 1: reminder that Venus is not a motionless world. Even though
• 36:43
  Speaker 1: the solid planet turns so slowly, the atmosphere is always moving.
• 36:48
  Speaker 1: Winds carry heat. Clouds carry chemical material. Droplets rise and fall.
• 36:55
  Speaker 1: Light enters and is reflected. Heat moves through the thick air.
• 37:00
  Speaker 1: And somewhere above the surface, enormous currents of atmosphere travel
• 37:05
  Speaker 1: around the planet in in only a handful of days.
• 37:08
  Speaker 1: The more you observe Venus, the more its contradictions begin
• 37:12
  Speaker 1: to gather. A slow planet with a fast sky. A
• 37:15
  Speaker 1: bright world with a hidden surface. Clouds that look soft
• 37:20
  Speaker 1: but contain acid. Gentle surface winds that can still move dust,
• 37:25
  Speaker 1: because the air itself is so dense. Rain that falls
• 37:29
  Speaker 1: but disappears before reaching the ground. A planet that seems
• 37:32
  Speaker 1: quiet from Earth. while its atmosphere is constantly in motion.
• 37:37
  Speaker 1: And there is something else you might notice, as you
• 37:40
  Speaker 1: drift upward and downward through these layers. There is a
• 37:43
  Speaker 1: particular height above Venus where the temperature and pressure begin
• 37:47
  Speaker 1: to feel surprisingly familiar. Not comfortable enough to breathe, not
• 37:51
  Speaker 1: safe enough to simply step outside, but physically, in a
• 37:55
  Speaker 1: few important ways, the environment becomes much closer to the
• 37:59
  Speaker 1: conditions you know on Earth. It is a curious region,
• 38:03
  Speaker 1: floating between the clouds and the furnace below, and perhaps,
• 38:08
  Speaker 1: for a little while, you can simply remain there, moving
• 38:11
  Speaker 1: gently with the atmosphere, while Venus turns slowly beneath you,
• 38:16
  Speaker 1: and the clouds continue their quiet journey around the planet.
• 38:22
  Speaker 1: You are still moving gently through the clouds of Venus.
• 38:26
  Speaker 1: Above you, the pale atmosphere continues its long journey around
• 38:30
  Speaker 1: the planet. Below you, The surface remains hidden beneath layers
• 38:34
  Speaker 1: of cloud. And somewhere between those two worlds, at roughly
• 38:39
  Speaker 1: 50 kilometres above the ground, something unexpected begins to happen.
• 38:44
  Speaker 1: The air becomes less extreme. The temperature becomes much closer
• 38:48
  Speaker 1: to what you might recognise from Earth. The pressure also
• 38:51
  Speaker 1: becomes surprisingly familiar. Even the pull of gravity beneath you
• 38:55
  Speaker 1: remains close to what you would experience at home. For
• 38:59
  Speaker 1: a moment, Venus seems almost gentle. Almost. Because this is
• 39:04
  Speaker 1: still Venus. The atmosphere is not something you could breathe.
• 39:08
  Speaker 1: The clouds around you still contain sulfuric acid. The chemistry
• 39:12
  Speaker 1: is still completely unsuitable for an unprotected human body. So
• 39:16
  Speaker 1: this is not a place where you could simply step
• 39:18
  Speaker 1: outside and breathe comfortably. But if you were enclosed inside
• 39:22
  Speaker 1: an airtight vehicle, something strange would happen. You could float
• 39:26
  Speaker 1: among the clouds while experiencing temperature and pressure that, in
• 39:30
  Speaker 1: a few important ways, were much closer to Earth-like conditions.
• 39:35
  Speaker 1: Imagine that for a moment. You are not standing on
• 39:38
  Speaker 1: the surface. You are not fighting against the crushing pressure below.
• 39:42
  Speaker 1: You are simply drifting. A sealed vehicle moves quietly through
• 39:46
  Speaker 1: the thick atmosphere. Outside, The clouds pass slowly across the windows.
• 39:52
  Speaker 1: Far below, hidden beneath kilometres of atmosphere, lies the furnace
• 39:57
  Speaker 1: of Venus. Far above, the darkness of space waits. And
• 40:02
  Speaker 1: between them, you are suspended in a world that feels
• 40:06
  Speaker 1: strangely familiar. The dense atmosphere would also provide something that
• 40:10
  Speaker 1: is unusual for a planet like Venus. Buoyancy. A sufficiently
• 40:15
  Speaker 1: light and sealed balloon or floating vehicle could, in principle,
• 40:20
  Speaker 1: remain aloft within these atmospheric layers. You would not need
• 40:23
  Speaker 1: to land. You would not need to touch the surface.
• 40:27
  Speaker 1: You could simply drift with the atmosphere. The idea sounds
• 40:31
  Speaker 1: almost peaceful. A floating world above a hostile world. A
• 40:35
  Speaker 1: quiet vessel, carried by winds that have been circling Venus
• 40:39
  Speaker 1: for countless years. Outside your window the clouds would continue
• 40:44
  Speaker 1: to move. The planet would continue its slow rotation. and
• 40:48
  Speaker 1: the sun would remain somewhere beyond the pale atmosphere. But
• 40:52
  Speaker 1: even in this relatively gentle region, Venus would remind you
• 40:56
  Speaker 1: that it is not Earth. The air itself would remain
• 40:59
  Speaker 1: poisonous to human lungs. The chemistry would remain harsh, and
• 41:04
  Speaker 1: below you would still be a surface where temperatures reach
• 41:07
  Speaker 1: extraordinary levels, and where the pressure becomes increasingly difficult to imagine.
• 41:12
  Speaker 1: So the similarity is only partial. Venus can briefly resemble
• 41:17
  Speaker 1: Earth in temperature and pressure, but resemblance is not the
• 41:21
  Speaker 1: same as safety. It is a small, strange island of
• 41:24
  Speaker 1: familiar conditions, floating inside a very unfamiliar planet. And perhaps
• 41:30
  Speaker 1: that is why Venus has always been so difficult to understand.
• 41:34
  Speaker 1: From Earth, you can see the planet easily. You can
• 41:38
  Speaker 1: see its light. You can follow its movement. You can
• 41:41
  Speaker 1: even watch it pass across the face of the sun
• 41:44
  Speaker 1: during those rare moments when the geometry is perfect. But
• 41:47
  Speaker 1: you cannot simply look down and see the ground. The
• 41:51
  Speaker 1: clouds stand between you and the surface. For centuries, the
• 41:55
  Speaker 1: landscape of Venus remained hidden. Then, in the 20th century,
• 42:00
  Speaker 1: humans began sending machines toward it. The first attempts were difficult.
• 42:06
  Speaker 1: Venus is not a forgiving destination. A spacecraft must travel
• 42:10
  Speaker 1: across the space between planets, enter the thick atmosphere, survive
• 42:15
  Speaker 1: enormous pressure, endure intense heat, and somehow continue communicating with Earth.
• 42:21
  Speaker 1: And yet, little by little, we began to reach it.
• 42:25
  Speaker 1: In the early years of exploration, spacecraft descended into the
• 42:29
  Speaker 1: clouds carrying instruments that could measure the environment below. The
• 42:33
  Speaker 1: Soviet Venera missions became pioneers in this effort. Venera 7
• 42:38
  Speaker 1: achieved something remarkable. In 1970, it became the first spacecraft
• 42:43
  Speaker 1: to successfully land on another planet and send data back
• 42:47
  Speaker 1: to Earth. The achievement was brief. The environment was so
• 42:51
  Speaker 1: extreme that the spacecraft did not survive for long. It
• 42:55
  Speaker 1: may even have fallen over during the landing. But it
• 42:58
  Speaker 1: managed to send back information about the surface. One of
• 43:02
  Speaker 1: the first measurements it returned was the extraordinary temperature at
• 43:06
  Speaker 1: ground level. around 475 degrees Celsius. A tiny machine had
• 43:12
  Speaker 1: reached another world. It had touched the ground, and for
• 43:16
  Speaker 1: a short while, it spoke to Earth. Then came Venera 8.
• 43:20
  Speaker 1: It provided more information about the environment near the surface,
• 43:24
  Speaker 1: and showed that visibility there could be surprisingly clear, with
• 43:28
  Speaker 1: a range of roughly one kilometre. The clouds that make
• 43:32
  Speaker 1: Venus look completely hidden from space do not extend all
• 43:35
  Speaker 1: the way down to the ground in the same way.
• 43:38
  Speaker 1: Near the surface, the atmosphere can be hazy, but the
• 43:41
  Speaker 1: landscape is not necessarily swallowed by an impenetrable fog. That
• 43:46
  Speaker 1: discovery opened another possibility. If a spacecraft could survive long enough,
• 43:51
  Speaker 1: perhaps it could actually see the ground. Then Venera 9 arrived.
• 43:56
  Speaker 1: And for the first time, humanity received an image from
• 43:59
  Speaker 1: the surface of Venus. Think about that quietly. For generations,
• 44:05
  Speaker 1: Venus had been a bright point in the sky. Then,
• 44:09
  Speaker 1: one day, a signal crossed the distance between planets, carrying
• 44:13
  Speaker 1: something completely different. Not a point of light. Not a
• 44:17
  Speaker 1: telescope image. A landscape. Rocks. Ground. The surface of another world. Later,
• 44:25
  Speaker 1: Venera missions returned more images, including colour photographs, along with
• 44:31
  Speaker 1: additional measurements of temperature, pressure, and the strange environment surrounding
• 44:36
  Speaker 1: the spacecraft. Each mission lasted only a limited amount of time.
• 44:41
  Speaker 1: The heat continued, the pressure continued, the atmosphere remained unforgiving,
• 44:46
  Speaker 1: but the information travelled outward, from Venus to Earth, across
• 44:51
  Speaker 1: the darkness, through space, a quiet stream of signals carrying
• 44:55
  Speaker 1: pieces of a hidden planet. And eventually, another method allowed
• 45:00
  Speaker 1: us to see even farther. Instead of trying to look
• 45:03
  Speaker 1: through the clouds with ordinary cameras, spacecraft began using radar.
• 45:08
  Speaker 1: Radar could pass through the thick cloud cover and reveal
• 45:12
  Speaker 1: the shape of the landscape beneath. Mountains could be mapped,
• 45:17
  Speaker 1: planes could be traced, volcanic structures could be identified. The
• 45:21
  Speaker 1: hidden face of Venus slowly emerged, not through ordinary sunlight,
• 45:27
  Speaker 1: but through invisible signals sent across the atmosphere. and returned
• 45:31
  Speaker 1: to distant instruments. It is a beautiful thought. Venus does
• 45:36
  Speaker 1: not easily show you its surface. So humanity learned to
• 45:39
  Speaker 1: look in another way. And as those maps became clearer,
• 45:43
  Speaker 1: the world beneath the clouds began to tell a much
• 45:46
  Speaker 1: older story. A story written not in photographs, but in stone.
• 45:52
  Speaker 1: A story of enormous volcanic landscapes, ancient surfaces, and changes
• 45:58
  Speaker 1: that unfolded across hundreds of millions of years. You can
• 46:02
  Speaker 1: remain here for another quiet moment, floating among the clouds.
• 46:07
  Speaker 1: Below you, the surface is still distant, but now you
• 46:11
  Speaker 1: know that it is there. You have heard its signals.
• 46:14
  Speaker 1: You have seen its rocks. And somewhere beneath your drifting vehicle,
• 46:19
  Speaker 1: an ancient world is waiting to be explored more deeply.
• 46:25
  Speaker 1: Beneath the clouds, the surface of Venus begins to take shape.
• 46:30
  Speaker 1: You have already imagined the first spacecraft reaching the ground,
• 46:34
  Speaker 1: surviving for a short while beneath the enormous heat and pressure,
• 46:38
  Speaker 1: and sending quiet signals back across the darkness. Now you
• 46:42
  Speaker 1: can imagine looking outward across that surface. At first it
• 46:46
  Speaker 1: may seem almost still. There are rocks, broad plains, distant
• 46:51
  Speaker 1: rises in the landscape. long stretches of ground extending beneath
• 46:55
  Speaker 1: the pale sky. But the longer you remain there, the
• 46:59
  Speaker 1: more you begin to notice that this is not a
• 47:01
  Speaker 1: quiet surface in the geological sense. Venus is a world
• 47:06
  Speaker 1: shaped by heat from within. A world with an enormous
• 47:10
  Speaker 1: volcanic history. Across its surface are countless volcanic structures, some
• 47:15
  Speaker 1: of them vast enough to make the largest volcanic landscapes
• 47:19
  Speaker 1: on Earth seem small by comparison. Among them, are about
• 47:25
  Speaker 1: 167 volcanoes, more than 100 kilometres across. You can let
• 47:30
  Speaker 1: that scale settle slowly. 100 kilometres is already a distance
• 47:35
  Speaker 1: that would take hours to cross by road, and Venus
• 47:38
  Speaker 1: has volcanic structures larger than that, scattered across its ancient surface.
• 47:44
  Speaker 1: There is something almost gentle about imagining them from far above.
• 47:49
  Speaker 1: You do not need to picture explosions You do not
• 47:52
  Speaker 1: need to imagine a dramatic eruption. Instead, imagine heat deep
• 47:56
  Speaker 1: beneath the ground, moving slowly upward through rock. Imagine the
• 48:01
  Speaker 1: surface gradually changing as molten material reaches places where the
• 48:06
  Speaker 1: crust has opened or weakened. And imagine that process happening
• 48:10
  Speaker 1: not for days or years, but across enormous stretches of
• 48:13
  Speaker 1: geological time. The surface of Venus contains vast plains that
• 48:18
  Speaker 1: appear to have been formed by ancient lava. Around 80%
• 48:23
  Speaker 1: of the planet's surface is thought to consist of cooled
• 48:26
  Speaker 1: lava plains. So when you look across Venus, you are
• 48:30
  Speaker 1: not simply looking at rock, you are looking at the
• 48:32
  Speaker 1: remains of ancient flows of molten material that once moved
• 48:37
  Speaker 1: across the surface and later cooled into stone. A landscape
• 48:42
  Speaker 1: that seems solid and permanent was once moving, slowly in places,
• 48:48
  Speaker 1: quickly perhaps in others, but eventually disappeared. it cooled. It
• 48:52
  Speaker 1: became ground, and that ground remained. This is one of
• 48:56
  Speaker 1: the ways Venus differs from Earth. Earth has a restless
• 49:00
  Speaker 1: outer surface. Huge pieces of its crust slowly move, collide,
• 49:06
  Speaker 1: separate and sink, carrying old landscapes away and creating new ones.
• 49:12
  Speaker 1: This process is known as plate tectonics. Venus does not
• 49:16
  Speaker 1: appear to have the same global system. Its outer crusts
• 49:20
  Speaker 1: seems to behave differently, and because the surface is not
• 49:23
  Speaker 1: continually recycled in the same way, ancient features can remain
• 49:28
  Speaker 1: visible for extraordinarily long periods. Scientists estimate that much of
• 49:33
  Speaker 1: Venus's present crust may be roughly 300 to 600 million
• 49:36
  Speaker 1: years old. that does not mean every rock on Venus
• 49:41
  Speaker 1: formed during one single moment. Rather, it suggests that much
• 49:46
  Speaker 1: of the visible surface may have been renewed during a
• 49:49
  Speaker 1: major period in the planet's geological history. One possibility is
• 49:54
  Speaker 1: that Venus experienced an enormous episode of resurfacing. Deep beneath
• 49:59
  Speaker 1: the crust, heat may have accumulated. The interior of the
• 50:03
  Speaker 1: planet may have become hot enough for huge amounts of
• 50:06
  Speaker 1: molten rock to rise toward the surface. That material could
• 50:11
  Speaker 1: then have spread outward, covering enormous areas with fresh lava.
• 50:16
  Speaker 1: Old landscapes would have disappeared beneath new rock. Mountains, plains,
• 50:21
  Speaker 1: valleys and ancient scars could have been buried. A new
• 50:25
  Speaker 1: Venus would have emerged from the old one. It is
• 50:28
  Speaker 1: an idea that remains a subject of scientific study, rather
• 50:32
  Speaker 1: than a completely settled story. But if such a global
• 50:36
  Speaker 1: resurfacing occurred … it would have transformed much of the planet.
• 50:40
  Speaker 1: You can imagine it not as a single sudden event,
• 50:43
  Speaker 1: but as a geological transformation unfolding over a vast span
• 50:48
  Speaker 1: of time. Heat rising, rock softening, molten material moving, surface cooling,
• 50:56
  Speaker 1: and then, slowly, a new landscape becoming still. There are
• 51:01
  Speaker 1: also impact craters scattered across Venus. Around 900 are known.
• 51:07
  Speaker 1: Each one is a quiet record of something that happened
• 51:10
  Speaker 1: beyond the planet, when a piece of rock from space
• 51:13
  Speaker 1: reached the surface and left its mark. But there are
• 51:16
  Speaker 1: surprisingly few small craters. The thick atmosphere explains part of this.
• 51:22
  Speaker 1: Small incoming objects can break apart as they travel downward
• 51:26
  Speaker 1: through the dense air. Some burn away before reaching the ground.
• 51:30
  Speaker 1: Others may fragment into smaller pieces. So the atmosphere does
• 51:35
  Speaker 1: more than trap heat. It also acts as a kind
• 51:38
  Speaker 1: of filter between Venus and the smaller objects wandering through
• 51:42
  Speaker 1: the solar system. Large enough objects can survive the journey.
• 51:46
  Speaker 1: Smaller ones may never complete it. And so, when you
• 51:50
  Speaker 1: look across the surface, the craters you see are not
• 51:53
  Speaker 1: a complete record of everything that has ever approached Venus.
• 51:57
  Speaker 1: The atmosphere has already erased some of that history before
• 52:01
  Speaker 1: it could reach the ground. There is something beautiful about
• 52:04
  Speaker 1: that idea. Even the empty spaces on Venus can tell
• 52:08
  Speaker 1: a story. A missing crater can be evidence of an
• 52:12
  Speaker 1: object that never made it through the clouds. A broad
• 52:15
  Speaker 1: lava plain can be evidence of ancient heat rising from below.
• 52:19
  Speaker 1: A volcanic mountain can be a reminder that the planet's
• 52:23
  Speaker 1: interior was once, and perhaps still is, active. And recent
• 52:29
  Speaker 1: analyses of old spacecraft observations have made the story even
• 52:32
  Speaker 1: more interesting. Scientists have found evidence suggesting that some volcanic
• 52:37
  Speaker 1: features may have changed over relatively short periods of time.
• 52:41
  Speaker 1: This raises the possibility that Venus is not simply an
• 52:45
  Speaker 1: ancient world whose geological story ended hundreds of millions of
• 52:49
  Speaker 1: years ago. Some parts of it may still be active today.
• 52:53
  Speaker 1: The evidence does not mean that the entire planet is
• 52:56
  Speaker 1: covered in constant eruptions. It does not mean that Venus
• 52:59
  Speaker 1: is always changing before our eyes. Instead, It suggests something quieter.
• 53:06
  Speaker 1: Deep inside the planet, heat may still be moving. Rock
• 53:10
  Speaker 1: may still be responding. And somewhere beneath those immense lava plains,
• 53:15
  Speaker 1: Venus may still be releasing a little of its ancient
• 53:18
  Speaker 1: internal energy. The world that looks frozen in time may
• 53:22
  Speaker 1: not be completely frozen at all. You can imagine the
• 53:26
  Speaker 1: surface resting beneath the pale sky. Nothing appears to move.
• 53:30
  Speaker 1: The rocks are silent. The planes stretch into the distance,
• 53:34
  Speaker 1: but far below your feet the interior of the planet
• 53:37
  Speaker 1: remains warm. Heat is still there, and perhaps, very slowly,
• 53:43
  Speaker 1: it is still finding its way outward. This is the
• 53:46
  Speaker 1: strange geological rhythm of Venus, a planet with an ancient face,
• 53:51
  Speaker 1: but perhaps not a completely quiet heart. And while the
• 53:54
  Speaker 1: surface carries the memory of heat rising from below, something
• 53:58
  Speaker 1: else is happening far above it. where the planet meets
• 54:01
  Speaker 1: the invisible stream of particles flowing outward from the Sun. There,
• 54:06
  Speaker 1: another mystery begins to emerge, a mystery about something Earth has,
• 54:11
  Speaker 1: Venus does not. Far above the ancient volcanic plains of Venus,
• 54:18
  Speaker 1: beyond the clouds and beyond the slow movement of the atmosphere,
• 54:22
  Speaker 1: the planet meets another kind of wind. It does not
• 54:26
  Speaker 1: come from the surface, it does not rise from the mountains,
• 54:30
  Speaker 1: It does not move through the clouds. It comes from
• 54:33
  Speaker 1: the sun. The sun is not only a distant light
• 54:35
  Speaker 1: in the sky, it is also continuously sending a stream
• 54:39
  Speaker 1: of charged particles outward through space, flowing quietly across the
• 54:43
  Speaker 1: solar system. On Earth, you are partly protected from this
• 54:47
  Speaker 1: stream by something invisible. Deep inside Earth, movement within the
• 54:52
  Speaker 1: planet generates a large magnetic field that extends far beyond
• 54:57
  Speaker 1: the atmosphere. You cannot see it, You cannot feel it.
• 55:01
  Speaker 1: And yet, it surrounds your planet like an invisible region
• 55:05
  Speaker 1: of influence. Venus is different. Despite its similarity to Earth
• 55:10
  Speaker 1: in size, mass and gravity, Venus does not have a
• 55:13
  Speaker 1: substantial magnetic field of its own. There is no strong
• 55:17
  Speaker 1: planetary magnetic shield surrounding it in the same way. At first,
• 55:22
  Speaker 1: this might seem like one more difference between two neighbouring worlds.
• 55:27
  Speaker 1: But the story is more interesting than simply saying that
• 55:29
  Speaker 1: Venus has no magnetic field. When the solar wind reaches Venus,
• 55:34
  Speaker 1: it meets the planet's thick upper atmosphere. The charged particles
• 55:38
  Speaker 1: from the Sun interact with the gases surrounding Venus, and
• 55:42
  Speaker 1: this interaction creates a temporary magnetic environment around the planet.
• 55:47
  Speaker 1: Scientists call this an induced magnetosphere. The name sounds technical,
• 55:53
  Speaker 1: but the idea can be imagined quite simply. Venus does
• 55:56
  Speaker 1: not bring its own magnetic field to the meeting. Instead,
• 56:01
  Speaker 1: a magnetic boundary forms because the atmosphere and the solar
• 56:04
  Speaker 1: wind encounter one another. The sun is moving outward. Venus
• 56:09
  Speaker 1: is sitting in its path. And between them, an invisible
• 56:13
  Speaker 1: region takes shape. You cannot see it. There is no sound,
• 56:17
  Speaker 1: no glow, no visible wall. But the interaction is happening continuously.
• 56:22
  Speaker 1: The solar wind flows around the planet. the upper atmosphere responds.
• 56:28
  Speaker 1: And some of the very light particles in that atmosphere
• 56:30
  Speaker 1: can gradually escape into space. This process is slow. It
• 56:35
  Speaker 1: is not something you would notice from one day to
• 56:37
  Speaker 1: the next. There is no sudden emptying of the atmosphere. Instead,
• 56:42
  Speaker 1: imagine a tiny number of particles being lifted away, again
• 56:47
  Speaker 1: and again, across enormous stretches of time. A little atmosphere lost,
• 56:52
  Speaker 1: then a little more. then another small amount. The process
• 56:56
  Speaker 1: continues beneath the constant light of the Sun. Over millions
• 57:01
  Speaker 1: and billions of years, even a slow process can become important.
• 57:06
  Speaker 1: And Venus leaves behind a remarkable signature of this interaction.
• 57:10
  Speaker 1: A long, faint stream of atmospheric material can extend away
• 57:14
  Speaker 1: from the planet, creating something that resembles the tail of
• 57:18
  Speaker 1: a comet. You might imagine Venus floating in the darkness.
• 57:23
  Speaker 1: its bright cloud-covered body surrounded by a nearly invisible extension
• 57:27
  Speaker 1: reaching behind it. The tail is not made of smoke.
• 57:31
  Speaker 1: It is not a trail that you could see with
• 57:33
  Speaker 1: your eyes. It is a thin stream of particles shaped
• 57:37
  Speaker 1: by the interaction between Venus and the solar wind. Under
• 57:42
  Speaker 1: certain conditions, this extended atmospheric tail can stretch enormous distances
• 57:48
  Speaker 1: and even reaching toward the region of space occupied by
• 57:52
  Speaker 1: Earth's orbit, two neighbouring planets, two atmospheres, two worlds moving
• 57:59
  Speaker 1: around the same sun, and between them, invisible particles can
• 58:03
  Speaker 1: travel through the darkness. There is something quietly beautiful about that.
• 58:09
  Speaker 1: You might think of Venus as a sealed world, isolated
• 58:13
  Speaker 1: beneath its clouds. But it is not isolated. The sun
• 58:18
  Speaker 1: reaches it, The solar wind reaches it. Particles leave it.
• 58:22
  Speaker 1: The atmosphere is continually interacting with the space around the planet.
• 58:27
  Speaker 1: And this brings you back to one of the larger
• 58:28
  Speaker 1: mysteries surrounding Venus. Why does it lack the strong intrinsic
• 58:33
  Speaker 1: magnetic field that Earth possesses? Scientists do not have one
• 58:38
  Speaker 1: final answer. Several possibilities have been considered. The answer may
• 58:43
  Speaker 1: involve the deep interior of Venus, the way heat moves
• 58:47
  Speaker 1: through the planet. the slow rotation of the world, or
• 58:50
  Speaker 1: the complicated events that shaped it early in its history.
• 58:54
  Speaker 1: There may have been enormous collisions. There may have been
• 58:58
  Speaker 1: changes in the planet's interior over billions of years. There
• 59:02
  Speaker 1: may be several reasons rather than one. And so, the
• 59:06
  Speaker 1: missing magnetic field remains part of Venus's larger mystery. It
• 59:11
  Speaker 1: is another example of how two planets can begin with
• 59:14
  Speaker 1: many similarities and still develop very different histories. Earth and
• 59:20
  Speaker 1: Venus are close in size. Their gravity is similar. Both
• 59:24
  Speaker 1: are rocky worlds. Both orbit the same star. both formed
• 59:28
  Speaker 1: from material that existed in the young solar system. And yet,
• 59:32
  Speaker 1: Earth became a world of oceans, continents, clouds and life,
• 59:37
  Speaker 1: while Venus became a world of crushing pressure, extreme heat
• 59:41
  Speaker 1: and acidic clouds. Some of the differences may have begun
• 59:45
  Speaker 1: very early. Perhaps Venus once had more water than it
• 59:49
  Speaker 1: has today. Scientists have considered the possibility that ancient Venus
• 59:54
  Speaker 1: may have experienced conditions very different from those we see now,
• 59:58
  Speaker 1: but the full story remains uncertain. It is unlikely that
• 1:00:02
  Speaker 1: one simple event transformed the planet. Instead, its history may
• 1:00:07
  Speaker 1: have been shaped by many slow processes interacting with one another. Sunlight, atmosphere, heat, water,
• 1:00:16
  Speaker 1: volcanic activity. the movement of material deep inside the planet,
• 1:00:21
  Speaker 1: the loss of particles into space, each process influencing the others,
• 1:00:25
  Speaker 1: sometimes gently, sometimes over immense periods of time. You can
• 1:00:30
  Speaker 1: imagine Venus not as a world that suddenly became hostile,
• 1:00:34
  Speaker 1: but as a world that slowly became itself. A little
• 1:00:37
  Speaker 1: more heat remained. The atmosphere changed. Water may have been lost.
• 1:00:42
  Speaker 1: The surface was reshaped. The interior continued to release heat.
• 1:00:47
  Speaker 1: The clouds became thick, the planet continued turning slowly, and
• 1:00:52
  Speaker 1: above it all, the solar wind continued to pass by.
• 1:00:57
  Speaker 1: There is no single moment when Venus became Venus. There
• 1:01:01
  Speaker 1: is only a long history, a history written across billions
• 1:01:05
  Speaker 1: of years. And perhaps this is where Venus becomes more
• 1:01:09
  Speaker 1: than simply another planet. Because when you look at Venus
• 1:01:12
  Speaker 1: … you are also looking at a reminder of how
• 1:01:15
  Speaker 1: different two similar worlds can become. Earth and Venus do
• 1:01:20
  Speaker 1: not need to be identical to teach you something about
• 1:01:23
  Speaker 1: one another. Their differences are part of the story. Earth
• 1:01:27
  Speaker 1: shows you one path a rocky planet can take. Venus
• 1:01:31
  Speaker 1: shows you another. Neither story is simple, and neither world
• 1:01:36
  Speaker 1: has remained unchanged. Even now, Venus continues to turn slowly.
• 1:01:42
  Speaker 1: Its clouds continue to race around it. Its surface continues
• 1:01:46
  Speaker 1: to hold the memory of ancient lava. Its upper atmosphere
• 1:01:50
  Speaker 1: continues to meet the wind of the sun. And tiny
• 1:01:54
  Speaker 1: particles continue to drift away into space. You can imagine
• 1:01:58
  Speaker 1: moving farther from the planet now. The clouds become smaller.
• 1:02:02
  Speaker 1: The volcanic plains become invisible. The pale disk of Venus
• 1:02:07
  Speaker 1: becomes a quiet shape against the darkness. From here... You
• 1:02:11
  Speaker 1: can no longer feel the pressure. You can no longer
• 1:02:14
  Speaker 1: feel the heat. You cannot see the acid clouds. You
• 1:02:17
  Speaker 1: cannot see the invisible magnetic boundary. You simply see the
• 1:02:22
  Speaker 1: planet again. The same bright world you noticed at the beginning.
• 1:02:26
  Speaker 1: Still beautiful. Still distant. Still turning slowly. And perhaps that
• 1:02:32
  Speaker 1: is the quietest lesson Venus offers. A planet can look
• 1:02:35
  Speaker 1: simple from far away. A small light. A pale sphere.
• 1:02:40
  Speaker 1: A neighbouring world. But when you move closer, layer by layer,
• 1:02:45
  Speaker 1: it becomes an entire history. Heat beneath clouds. Clouds above stone.
• 1:02:51
  Speaker 1: Stone shaped by ancient fire. An atmosphere slowly interacting with sunlight.
• 1:02:57
  Speaker 1: Particles drifting into space. And somewhere within all of this,
• 1:03:01
  Speaker 1: unanswered questions remain. You do not need to solve them tonight.
• 1:03:06
  Speaker 1: You can simply let Venus continue its slow journey around
• 1:03:09
  Speaker 1: the sun. Let the clouds move quietly around its surface.
• 1:03:14
  Speaker 1: Let the invisible solar wind pass through the darkness. And
• 1:03:18
  Speaker 1: let the distant planet remain there, quietly reminding you that
• 1:03:22
  Speaker 1: even worlds born close together can follow very different paths.
• 1:03:27
  Speaker 1: For now, you can drift a little farther away. The
• 1:03:31
  Speaker 1: bright disk becomes smaller. The darkness becomes larger. And Earth
• 1:03:36
  Speaker 1: begins to feel closer again, floating somewhere nearby, in the
• 1:03:41
  Speaker 1: same vast solar system beneath its own familiar sky. You
• 1:03:46
  Speaker 1: are safe. There is nothing more you need to do.
• 1:03:49
  Speaker 1: Just listen and drift. The stars will remain where they are.
• 1:03:53
  Speaker 1: The planets will continue moving. And Venus, far away in
• 1:03:57
  Speaker 1: the darkness, will keep turning slowly beneath its pale clouds,
• 1:04:03
  Speaker 1: carrying its ancient mysteries quietly with it. And so, Your
• 1:04:09
  Speaker 1: journey around Venus can now drift quietly toward its end.
• 1:04:14
  Speaker 1: You began by looking at a small, bright light in
• 1:04:17
  Speaker 1: the evening sky, a distant world that seemed peaceful and familiar,
• 1:04:22
  Speaker 1: almost like a second Earth resting quietly beyond the darkness.
• 1:04:26
  Speaker 1: But as you moved closer, Venus slowly revealed another side
• 1:04:30
  Speaker 1: of itself, a world that turns backward so slowly that
• 1:04:35
  Speaker 1: its year is shorter than its full rotation. a world
• 1:04:38
  Speaker 1: almost the same size as Earth, yet wrapped in an
• 1:04:42
  Speaker 1: atmosphere so dense that the air itself presses down like
• 1:04:46
  Speaker 1: an invisible ocean, a world where sunlight enters, warmth gathers,
• 1:04:51
  Speaker 1: and heat remains, until the surface becomes one of the
• 1:04:55
  Speaker 1: hottest places among all the planets. Above that surface, clouds
• 1:05:00
  Speaker 1: filled with sulphuric acid move around the planet far faster
• 1:05:04
  Speaker 1: than the planet itself turns, and beneath those clouds, Ancient
• 1:05:09
  Speaker 1: lava plains stretch quietly across a world that may have
• 1:05:13
  Speaker 1: been reshaped by immense volcanic forces long ago. You heard
• 1:05:17
  Speaker 1: the quiet signals of the first spacecraft to reach the surface.
• 1:05:22
  Speaker 1: You imagined the first photographs arriving from beneath the clouds,
• 1:05:26
  Speaker 1: and you drifted through the strange region high above the surface,
• 1:05:30
  Speaker 1: where the temperature and pressure can become surprisingly familiar, even
• 1:05:34
  Speaker 1: though the atmosphere itself remains completely unsuitable for breathing. Farther away,
• 1:05:40
  Speaker 1: you imagine the invisible wind of the sun flowing around Venus,
• 1:05:44
  Speaker 1: interacting with its upper atmosphere, carrying tiny particles gradually outward
• 1:05:49
  Speaker 1: into space. And through all of this, Venus remained what
• 1:05:54
  Speaker 1: it was at the beginning, a small, bright world, still turning,
• 1:05:59
  Speaker 1: still circling the sun, still hidden beneath its pale clouds.
• 1:06:04
  Speaker 1: Perhaps that is what makes Venus so quietly fascinating. You
• 1:06:08
  Speaker 1: can look at it from Earth and see only a
• 1:06:10
  Speaker 1: point of light. But behind that light is an entire world,
• 1:06:15
  Speaker 1: with its own rhythm, its own history, its own ancient landscapes,
• 1:06:20
  Speaker 1: and its own unanswered questions. You do not need to
• 1:06:23
  Speaker 1: remember every number. You do not need to remember every
• 1:06:27
  Speaker 1: scientific name. You do not need to solve the mysteries
• 1:06:30
  Speaker 1: of Venus tonight. You can simply let the images remain.
• 1:06:34
  Speaker 1: The slow-turning planet. The racing clouds. the warm air, the
• 1:06:40
  Speaker 1: ancient stone, the distant sunlight, the invisible particles drifting away
• 1:06:45
  Speaker 1: into space. And now, as you begin to drift farther
• 1:06:48
  Speaker 1: from Venus, the planet becomes smaller again. The clouds become
• 1:06:53
  Speaker 1: a pale, quiet circle. The surface disappears. The atmosphere becomes invisible.
• 1:07:00
  Speaker 1: The strange world that seemed so enormous when you were
• 1:07:03
  Speaker 1: close to it becomes once again a small point of
• 1:07:07
  Speaker 1: light among countless others. And somewhere nearby, Earth continues its
• 1:07:12
  Speaker 1: own slow journey around the same sun, your own world
• 1:07:16
  Speaker 1: beneath its familiar atmosphere, its oceans, its changing seasons, its
• 1:07:21
  Speaker 1: clouds and its quiet nights. For now, you can let
• 1:07:25
  Speaker 1: yourself return there. There is nothing to do, nothing to solve,
• 1:07:30
  Speaker 1: nothing you need to hold on to. You are safe.
• 1:07:33
  Speaker 1: Just listen and drift. The planets will continue moving while
• 1:07:37
  Speaker 1: you rest. Venus will continue its slow, backward turning. Its
• 1:07:42
  Speaker 1: clouds will continue their quiet journey around the planet. The
• 1:07:46
  Speaker 1: sun will continue shining across the solar system. And far
• 1:07:49
  Speaker 1: beyond all of them, the stars will remain quietly scattered
• 1:07:53
  Speaker 1: through the darkness. So let your breathing become slow and comfortable.
• 1:07:58
  Speaker 1: Let the sounds around you become softer. Let the room
• 1:08:01
  Speaker 1: you are in feel distant and still. You have travelled
• 1:08:04
  Speaker 1: far enough tonight. You can rest now. And perhaps, sometime
• 1:08:10
  Speaker 1: in the future, when you see that bright evening light again,
• 1:08:14
  Speaker 1: you may remember that beneath its peaceful glow is a
• 1:08:17
  Speaker 1: world of immense heat, ancient stone, racing clouds, and mysteries
• 1:08:23
  Speaker 1: that are still being discovered. But tonight, you do not
• 1:08:27
  Speaker 1: need to follow those mysteries any farther. You can simply
• 1:08:30
  Speaker 1: let Venus drift away into the darkness. small, quiet, distant,
• 1:08:36
  Speaker 1: still turning. And while the universe continues its slow motion
• 1:08:40
  Speaker 1: around you, you can close your eyes, let go of
• 1:08:44
  Speaker 1: the remaining thoughts, and drift gently into sleep. Rest well.
• 1:08:49
  Speaker 1: The planets will keep turning, the clouds will keep moving,
• 1:08:53
  Speaker 1: the stars will keep shining, and Venus will remain there,
• 1:08:57
  Speaker 1: quietly circling the sun, long after you have fallen asleep.