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(upbeat music)
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- [Narrator] Scientists have
made a staggering discovery.
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A planet circling the
sun's nearest neighbor
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with temperatures that could
allow liquid water to flow.
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What will it take to go there,
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to explore it?
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The answer is speed.
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Laser driven spaceships.
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Anti-matter engines.
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Warp drive, right out of science fiction.
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How far,
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how fast can our technology to take us?
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(upbeat music)
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(moves in to light music)
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It's a journey that has lasted a century.
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A spacecraft approaches its destination,
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a planet beyond our solar system
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and a future beyond our imagination.
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Touchdown will mark a
milestone in our eternal quest
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to expand our horizons,
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to explore and to survive.
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It's not the first time we've struck out
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into the void against all odds.
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For much of our history, the
oceans were the great unknown.
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Several thousand years ago,
a seafaring culture emerged
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in the Southwest Pacific.
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Riding ocean and wind currents,
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the Polynesians sailed East,
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navigating by the stars,
the Moon and the Sun.
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Over centuries of time,
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they claimed the Pacific Ocean
island by distant island.
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It was one of the most
expansive migrations
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in human history.
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Their furthest reach, Easter Island,
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was over 2000 kilometers
from the nearest land.
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(upbeat music)
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Today we have begun to reach beyond
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our planetary shores,
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across distances so vast,
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we measure them in light years.
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That's how far light travels in a year,
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almost 10 trillion kilometers.
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Our roadmap leads us out
into the southern sky.
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There, a little over four light years away
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you'll find our sun's nearest neighbors,
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a dim red dwarf star
called Proxima Centauri.
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And a pair of Sun-like
stars called Alpha Centauri.
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Go beyond them and you've entered
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the local bubble, a giant
empty region cleared
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of gas by a star that exploded long ago.
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Within this bubble, 50
light years from Earth,
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are 150 stars bright enough
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to be seen with the naked eye.
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(light music)
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Nestled among them are 2000 smaller stars
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visible only with a powerful telescope.
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How many have planets?
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Could any serve as stations
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on our way out to explore the galaxy?
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(upbeat music)
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Our first stop, no doubt,
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is a planet orbiting around
the star nearest to Earth,
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Proxima Centauri.
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About one third larger than Earth,
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it's a very different kind of planet.
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One side facing away from its
star is dark and freezing.
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The other side facing inward,
is forever bright and warm.
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Did life flourish here?
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Could humans survive?
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The key is whether there's an atmosphere
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and water on the surface.
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These would be signs
that there's a climate
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and temperatures moderate
enough to support life.
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If Proxima B or any other
planet in the solar neighborhood
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proves to be habitable, the
call will certainly be heard
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to mount an expedition to
see and explore it up close.
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But to get there in the short
course of a human lifetime
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will take whole new types of spacecraft
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we have yet to build,
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whole new designs that can
propel us to extreme speeds.
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The discovery of Proxima B was
part of an intensive campaign
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to find worlds like Earth
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in the neighborhood of our Sun.
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Increasingly, the hunt for
planets combines the enormous
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light gathering power of
giant new observatories
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on the ground with a growing
fleet of telescopes in space.
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More than just identifying
the presence of planets,
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these instruments allow us
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to measure surface temperatures,
detect atmospheres,
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and look for the chemical
signatures of life.
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Astronomers are devising whole
new tests of habitability.
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One group used the Hubble Space Telescope
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to probe a series of
seven planets recently
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found orbiting an ultra cool dwarf star
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40 light years away called Trappist I.
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Each of these planets is
roughly the size of Earth.
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Three orbit within the habitable zone.
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At just the right distance
from the parent star
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and with the right temperature
to support liquid water.
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What are the chances
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they actually harbor oceans
and rivers and lakes?
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Red dwarf stars like Trappist I are known
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to emit large and violent flares.
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Over time, solar radiation
acts to split molecules
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of water in a planet's atmosphere.
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Hydrogen atoms liberated in the split
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then waft into space,
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leaving the oxygen to bind
with rocks on the surface.
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This same process has been
documented on the planet Mars.
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In its early years,
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there is thought to have been enough water
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to carve networks
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of river and lake beds.
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Over time, these stores
of water disappeared
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along with Mars' chance of nurturing life.
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To find out whether the planets
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of Trappist I have been
stripped of their water,
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astronomers measured the amount
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of ultraviolet light striking them,
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an indication of their
exposure to solar flares.
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They found that the
innermost planets are bathed
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in ultraviolet light and
are most likely bone dry.
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By contrast,
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the outermost planets have
been spared the radiation.
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It's possible they have kept the stores
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of water acquired during their
birth, whether liquid or ice.
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(light music)
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Based on a statistical analysis
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of solar systems discovered so far,
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one study estimates that there is at least
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one planet like Earth
within 20 light years.
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(upbeat music)
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Astronomers may have already found it.
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Each night in this control room
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at the La Silla Observatory in Chile,
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astronomers conduct the
world's most intensive hunt
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for planets in the
neighborhood of the Sun.
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They work with an older telescope,
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commissioned in the year 1977.
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It has a relatively small
mirror at 3.6 meters in diameter
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but it's outfitted with a
spectrographic technology
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that allows astronomers to finally parse
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the light of nearby stars.
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It does this by recording
subtle shifts in their light
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caused by the gravitational
tug of planets.
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Among their targets is a star that lies
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just below the constellation of Leo,
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11 light years from Earth.
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Ross 128 is a red dwarf
star like Proxima Centauri.
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Orbiting this star,
within the habitable zone,
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astronomers have found a planet
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slightly larger than Earth.
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(light music)
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Because the star is relatively quiescent,
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the planet may not have endured
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destructive blasts of radiation.
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In the coming years,
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astronomers will use
powerful ground telescopes
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to probe the planet's atmosphere.
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They are looking for the presence
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of biomarkers such as oxygen,
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and other evidence of a habitable climate.
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They'll also look for clues
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to the early evolution of our own planet
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and ultimately for an answer
to the age old question,
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are we alone in the universe?
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- Should we ever decide it's worth
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going there for a closeup
look, we might want to wait.
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Ross 128 is actually moving toward us,
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in the blink of a cosmic eye,
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79,000 years from now,
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it will become our son's nearest neighbor.
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Proxima Centauri,
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Trappist I and Ross 128
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are among the first targets
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in what is shaping up to be
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the golden age of planet hunting.
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The Transit Exoplanet Satellite, TES,
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has found evidence of over
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5,000 planets orbiting nearby stars
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that astronomers hope to
scan in the coming years.
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(light music)
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Many are like those found
around the star HD 20749,
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slightly smaller than our
Sun, and 53 light years away.
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The surface of Planet C likely hovers
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around 400 degrees Celsius.
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It's so close to the star that it whips
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around it every eight Earth days.
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Planet B is a gas giant,
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23 times the mass of Earth,
within a deep layer of clouds
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temperatures average
around 150 degrees Celsius.
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The sun-like star Pi Mensa hosts
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a planet twice the size of Earth.
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Its surface temperature is
over 900 degrees Celsius.
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Then there's this planet,
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around the red dwarf star TOI0-00
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roughly the size of Earth,
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it's tucked just inside the habitable zone
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of its parent star.
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Following up on data from TES,
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planet hunters used the powerful detectors
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of the James Webb Space Telescope
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to confirm its first planet.
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At 99% the size of Earth,
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it orbits the Red dwarf star LHS-475.
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This planet will no doubt be the subject
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of intensive study in coming years.
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(light music)
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Inevitably, the discovery of planets
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around nearby stars has spurred debate
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about the imperatives of
interstellar missions.
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The physicist Stephen Hawking,
was one of a growing number
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of scientists concerned about a cloud
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of uncertainties
surrounding Earth's future.
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- Pollution.
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Overpopulation.
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War.
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Climate change and ecological collapse.
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We have no choice, they say,
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but to develop the technologies
needed to not only travel
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to other solar systems, but
to survive in alien realms.
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The dream of settling distant worlds
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is as old as the rocket itself.
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Back in the early years
of the 20th century
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the Russian space visionary
Konstantin Sulkovsky
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believed humans would one
day ascend to the stars.
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They would evolve into a whole new species
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he called homo cosmicus.
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Sulkovsky laid out the
physics of the rocket.
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His famous rocket equation describes
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the basic principle of acceleration.
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It's the force of mass expelled
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at high velocity out the back of a rocket.
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Versus the overall mass of the rocket.
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(light music)
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Decades later in the
1960s with the space age
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in full swing another Russian scientist,
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Nikolai Kardashev,
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described space faring civilizations
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as the product of a long
range technological evolution.
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He defined level one as
a planetary civilization
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with the ability to tap
into energy equivalent
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to that of the sun striking our planet.
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At this basic level,
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a planetary civilization would exceed
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our current energy generating capacity
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by five orders of magnitude.
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It may take us centuries
to advance that far.
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It may take thousands or even millions
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of years to reach level two,
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the ability to harness
the energy equivalent
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of a star, or level three,
the energy of a galaxy.
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In theory, a civilization
with that degree of
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sophistication could wander
the galaxy mining raw materials
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from planetary bodies
while generating energy
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from technologies we can scarcely imagine.
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Advancing that far does not mean
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we can afford to abandon Earth.
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According to a recent rethinking
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of Kardashev's theories,
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maintaining the health of our biosphere
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will be crucial to the development
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of interstellar technologies.
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In this view,
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00:20:19,920 --> 00:20:22,950
interstellar flight will
flow from successful efforts
266
00:20:22,950 --> 00:20:25,817
to solve humanity's growing energy needs,
267
00:20:25,817 --> 00:20:28,890
with technologies that are more efficient,
268
00:20:28,890 --> 00:20:30,993
powerful, and safe.
269
00:20:37,980 --> 00:20:40,590
Indeed, radically more potent fuels
270
00:20:40,590 --> 00:20:43,410
and engines could even
pose serious dangers
271
00:20:43,410 --> 00:20:45,600
to the very environments that allow us
272
00:20:45,600 --> 00:20:47,073
to develop and test them.
273
00:20:48,282 --> 00:20:51,032
(dramatic music)
274
00:20:56,430 --> 00:20:57,960
In this way of thinking,
275
00:20:57,960 --> 00:21:00,840
to advance toward a planetary civilization
276
00:21:00,840 --> 00:21:03,030
means producing energy in ways
277
00:21:03,030 --> 00:21:05,283
that actually safeguard Earth.
278
00:21:14,910 --> 00:21:17,700
What leaps in science and engineering
279
00:21:17,700 --> 00:21:20,343
will interstellar
technologies depend upon?
280
00:21:23,400 --> 00:21:28,400
How far, and how fast can they take us.
281
00:21:38,310 --> 00:21:41,820
The speeds we can reach
depend on the technologies
282
00:21:41,820 --> 00:21:44,973
we employ and the power that drives them.
283
00:21:52,650 --> 00:21:55,143
Power is often measured in joules.
284
00:21:56,040 --> 00:21:59,310
The amount needed to
lift a 100 gram object
285
00:21:59,310 --> 00:22:01,473
one meter against Earth's gravity.
286
00:22:04,980 --> 00:22:06,900
The metabolism of an average person
287
00:22:06,900 --> 00:22:11,900
at rest produces 100 joules
per second or 100 watts.
288
00:22:14,460 --> 00:22:16,503
That's the same as a light bulb.
289
00:22:22,020 --> 00:22:23,580
An elite runner traveling
290
00:22:23,580 --> 00:22:27,843
at almost 40 kilometers per
hour generates 1500 watts.
291
00:22:30,360 --> 00:22:33,090
Using the technology of a bicycle
292
00:22:33,090 --> 00:22:34,710
we use that same wattage
293
00:22:34,710 --> 00:22:37,023
to top 66 kilometers per hour.
294
00:22:43,290 --> 00:22:47,313
On the ground, this is
our speediest machine,
295
00:22:48,900 --> 00:22:53,170
a race car can reach speeds
of 350 kilometers per hour
296
00:22:54,240 --> 00:22:55,890
with an engine that converts
297
00:22:55,890 --> 00:22:58,920
the potential energy packed into gasoline,
298
00:22:58,920 --> 00:23:02,040
about 40 million joules per kilo,
299
00:23:02,040 --> 00:23:04,413
into the kinetic energy of motion.
300
00:23:05,820 --> 00:23:09,033
It's held back by friction
from the road and the air.
301
00:23:10,980 --> 00:23:15,783
One way to fight friction,
soar into the upper atmosphere.
302
00:23:19,020 --> 00:23:24,020
The SR-71 Blackbird flies at
3,500 kilometers per hour,
303
00:23:25,440 --> 00:23:27,963
10 times faster than a race car.
304
00:23:30,330 --> 00:23:32,830
As much power as a jet can muster
305
00:23:34,290 --> 00:23:37,743
a full tank buys only
a few hours of flight.
306
00:23:41,760 --> 00:23:44,883
Rocketing into space
is even less efficient.
307
00:23:48,630 --> 00:23:50,670
To rise into Earth orbit,
308
00:23:50,670 --> 00:23:53,400
a giant Saturn V rocket must
309
00:23:53,400 --> 00:23:57,060
hit 28,000 kilometers per hour,
310
00:23:57,060 --> 00:23:59,620
almost 10 times faster than a jet
311
00:24:03,870 --> 00:24:08,070
But the faster it goes,
the more fuel it burns,
312
00:24:08,070 --> 00:24:09,693
the more it has to carry.
313
00:24:12,210 --> 00:24:15,000
To get Apollo astronauts into space
314
00:24:15,000 --> 00:24:17,010
and on their way to the moon.
315
00:24:17,010 --> 00:24:22,010
A Saturn five rocket had to lug
16 times its weight in fuel.
316
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As inefficient as chemical rockets are,
317
00:24:28,140 --> 00:24:31,323
they have served the vast
imperatives of the space age.
318
00:24:37,530 --> 00:24:39,240
Since the 1960s,
319
00:24:39,240 --> 00:24:41,250
we've used them to launch thousands
320
00:24:41,250 --> 00:24:44,553
of satellites for communications
and military purposes,
321
00:24:45,906 --> 00:24:49,293
for studying the Earth
and peering into space.
322
00:24:51,540 --> 00:24:52,830
And we've used rockets
323
00:24:52,830 --> 00:24:55,923
to send a succession of
astronauts into Earth orbit.
324
00:25:04,950 --> 00:25:07,290
The now retired Space Shuttle served
325
00:25:07,290 --> 00:25:09,123
as a platform for research,
326
00:25:10,470 --> 00:25:13,413
for launching and servicing
the Hubble Space Telescope,
327
00:25:15,540 --> 00:25:18,393
and for building the
International Space Station,
328
00:25:22,380 --> 00:25:24,510
a successor to the Russian Mir,
329
00:25:24,510 --> 00:25:26,553
and American Skylab stations.
330
00:25:27,390 --> 00:25:31,833
The International Space Station
began to take shape in 1998.
331
00:25:37,740 --> 00:25:40,050
It has become the largest collaborative
332
00:25:40,050 --> 00:25:42,783
engineering project in human history.
333
00:25:46,200 --> 00:25:49,890
This sprawling structure
posts a complex arrangement
334
00:25:49,890 --> 00:25:54,890
of modules and nodes and a
network of labs and living areas.
335
00:25:57,960 --> 00:26:00,060
Here astronauts are learning
336
00:26:00,060 --> 00:26:02,850
to live for extended periods of time
337
00:26:02,850 --> 00:26:05,640
apart from the gravity, climate systems,
338
00:26:05,640 --> 00:26:08,103
and comforts of our home planet.
339
00:26:11,220 --> 00:26:12,564
From Earth,
340
00:26:12,564 --> 00:26:16,773
rockets deliver resupply missions
up to six times each year.
341
00:26:18,240 --> 00:26:22,350
These unmanned capsules from
Russia and the United States
342
00:26:22,350 --> 00:26:24,210
carry hundreds of meals,
343
00:26:24,210 --> 00:26:27,273
new equipment and scientific experiments.
344
00:26:30,150 --> 00:26:32,310
The International Space Station has become
345
00:26:32,310 --> 00:26:35,100
a hub for zero gravity science.
346
00:26:35,100 --> 00:26:36,600
At any given time,
347
00:26:36,600 --> 00:26:38,760
the crew is conducting pointed research
348
00:26:38,760 --> 00:26:41,850
into life support systems
and preparing data
349
00:26:41,850 --> 00:26:44,680
for publication in science journals.
350
00:26:44,680 --> 00:26:47,263
(upbeat music)
351
00:26:49,380 --> 00:26:52,500
Proponents of this work see
it laying the groundwork
352
00:26:52,500 --> 00:26:55,683
for longer and more
ambitious manned missions.
353
00:26:56,910 --> 00:26:59,493
There are a host of
challenges to overcome.
354
00:27:05,120 --> 00:27:08,853
Beyond recycling waste and
the internal atmosphere,
355
00:27:08,853 --> 00:27:11,400
life support systems must include
356
00:27:11,400 --> 00:27:13,413
the ability to grow food.
357
00:27:17,730 --> 00:27:20,340
On missions far beyond Earth,
358
00:27:20,340 --> 00:27:22,170
living compartments must protect
359
00:27:22,170 --> 00:27:24,813
against solar radiation and cosmic rays.
360
00:27:27,780 --> 00:27:29,760
Once these problems are solved,
361
00:27:29,760 --> 00:27:32,010
some proponents envision the construction
362
00:27:32,010 --> 00:27:34,143
of bases in orbit around the sun,
363
00:27:36,923 --> 00:27:39,900
with factories or supply hubs
364
00:27:39,900 --> 00:27:42,543
to support a network of remote colonies.
365
00:27:50,460 --> 00:27:53,490
Whether we send people to explore Mars
366
00:27:53,490 --> 00:27:56,910
or to mine rare minerals on asteroids,
367
00:27:56,910 --> 00:27:58,530
we'll have to overcome the power
368
00:27:58,530 --> 00:28:00,783
and speed limits of the space age.
369
00:28:08,580 --> 00:28:11,880
Right now, because of the
amount of fuel needed just
370
00:28:11,880 --> 00:28:16,260
to get into space, most
long distance spacecraft
371
00:28:16,260 --> 00:28:18,483
can only coast to their destinations.
372
00:28:27,750 --> 00:28:30,030
The Twin Voyager spacecraft got
373
00:28:30,030 --> 00:28:34,290
around this by using the
pole of Jupiter's gravity
374
00:28:34,290 --> 00:28:36,063
as a planetary slingshot.
375
00:28:40,020 --> 00:28:43,233
Racing out at 62,000 kilometers per hour,
376
00:28:44,070 --> 00:28:46,623
more than double the speed of a Saturn V,
377
00:28:47,640 --> 00:28:50,460
Voyager 2 became the first spacecraft
378
00:28:50,460 --> 00:28:52,263
to exit the solar system.
379
00:28:55,290 --> 00:28:57,780
But as fast as it's going
380
00:28:57,780 --> 00:29:02,703
it will need another 73,000
years to reach Proxima Centauri.
381
00:29:07,710 --> 00:29:10,920
To make long distance
space travel efficient,
382
00:29:10,920 --> 00:29:14,220
whether it's humans or
robots making the journey,
383
00:29:14,220 --> 00:29:16,533
we'll have to reinvent the rocket.
384
00:29:21,078 --> 00:29:24,078
(suspenseful music)
385
00:29:25,710 --> 00:29:29,280
The search for faster, more
advanced spacecraft began
386
00:29:29,280 --> 00:29:33,423
in the 1960s in the shadow
of the nuclear arms race.
387
00:29:35,100 --> 00:29:38,763
Nuclear bombs release energy
by splitting the atom.
388
00:29:40,211 --> 00:29:42,360
Imagine if that potential
389
00:29:42,360 --> 00:29:45,930
could be harnessed to propel a spacecraft.
390
00:29:45,930 --> 00:29:49,053
Scientists tested a
whole new type of rocket,
391
00:29:50,190 --> 00:29:53,973
a vehicle propelled by
small nuclear explosions.
392
00:29:58,890 --> 00:30:01,860
They envision an orbiting space station
393
00:30:01,860 --> 00:30:04,713
as the launchpad for the Orion spacecraft.
394
00:30:10,405 --> 00:30:12,000
(upbeat music)
395
00:30:12,000 --> 00:30:14,520
A series of controlled nuclear blasts
396
00:30:14,520 --> 00:30:16,590
set off behind the craft
397
00:30:16,590 --> 00:30:19,743
would accelerate it to
10% the speed of light.
398
00:30:20,790 --> 00:30:23,790
Orion would've been
able to reach Proxima B
399
00:30:23,790 --> 00:30:26,793
in just over four decades of Earth time.
400
00:30:28,410 --> 00:30:31,473
Plans for this spacecraft
never got off the ground.
401
00:30:32,310 --> 00:30:36,273
The technology was unproven,
and perhaps unsafe.
402
00:30:39,122 --> 00:30:41,850
In the 1970s with interstellar flight
403
00:30:41,850 --> 00:30:46,080
still in their sights, a
group of British engineers
404
00:30:46,080 --> 00:30:49,923
designed a 200 meter long
craft called Daedalus.
405
00:30:54,150 --> 00:30:58,053
It would use another type
of nuclear power - fusion.
406
00:31:00,120 --> 00:31:02,463
That's the energy that lights up the sun,
407
00:31:04,110 --> 00:31:07,020
generated when gravity
forces atoms together
408
00:31:07,020 --> 00:31:09,273
under immense heat and pressure.
409
00:31:12,690 --> 00:31:15,644
Just a gram of fusion
fuel could yield energy
410
00:31:15,644 --> 00:31:19,263
in the range of 200 billion joules.
411
00:31:22,740 --> 00:31:26,010
The idea was to produce
an extremely hot gas
412
00:31:26,010 --> 00:31:29,163
that would propel the craft
by blasting it out the back.
413
00:31:32,640 --> 00:31:35,160
After accelerating through two stages,
414
00:31:35,160 --> 00:31:38,343
it could cruise along at
12% the speed of light,
415
00:31:40,200 --> 00:31:41,670
but this required Daedalus
416
00:31:41,670 --> 00:31:45,210
to carry more than 40,000 tons of fuel
417
00:31:45,210 --> 00:31:47,700
and there'd be nothing
left to slow it down.
418
00:31:47,700 --> 00:31:49,683
Once it approached its destination.
419
00:31:52,200 --> 00:31:54,720
As it flew past its target
420
00:31:54,720 --> 00:31:57,760
at 129 million kilometers per hour
421
00:31:58,620 --> 00:32:01,450
it would deploy a fleet
of robotic explorers
422
00:32:01,450 --> 00:32:03,033
to go in for a look.
423
00:32:06,840 --> 00:32:09,120
Daedalus was never built,
424
00:32:09,120 --> 00:32:11,310
but the completeness of the design
425
00:32:11,310 --> 00:32:14,463
has inspired new generations of dreamers.
426
00:32:18,876 --> 00:32:21,030
(light music)
427
00:32:21,030 --> 00:32:24,815
Today, one group of scientists
believes it may have
428
00:32:24,815 --> 00:32:28,113
a way to reach Proxima B more efficiently.
429
00:32:31,230 --> 00:32:33,750
The concept begins with a solar power
430
00:32:33,750 --> 00:32:36,123
generating station orbiting Earth.
431
00:32:38,550 --> 00:32:43,550
It's lined with lasers each
aimed at a tiny spacecraft
432
00:32:43,650 --> 00:32:46,953
a futuristic version of
that Polynesian sailboat.
433
00:32:55,980 --> 00:32:59,520
The force exerted by
each laser beam is small,
434
00:32:59,520 --> 00:33:02,550
but together in frictionless space
435
00:33:02,550 --> 00:33:04,920
they can propel a space sale
436
00:33:04,920 --> 00:33:06,573
with staggering success,
437
00:33:08,130 --> 00:33:10,593
to 20% the speed of light.
438
00:33:26,040 --> 00:33:27,950
In just 20 years,
439
00:33:27,950 --> 00:33:32,193
a fleet of laser powered
craft approaches Proxima B,
440
00:33:34,980 --> 00:33:37,740
they send their data
bouncing from one craft
441
00:33:37,740 --> 00:33:41,373
to the next on a four year
return journey to Earth.
442
00:33:42,930 --> 00:33:45,610
If Proxima B proves a worthy destination
443
00:33:47,070 --> 00:33:48,270
there are technologies
444
00:33:48,270 --> 00:33:51,993
on the drawing board that
promise an even faster ride.
445
00:33:56,288 --> 00:33:57,930
- What if we could tap into
446
00:33:57,930 --> 00:34:01,473
the stuff of science
fiction - anti-matter?
447
00:34:08,220 --> 00:34:10,830
It's the product of high energy radiation
448
00:34:10,830 --> 00:34:12,843
that rips through our solar system.
449
00:34:16,380 --> 00:34:21,000
When cosmic rays smash into
atoms in our upper atmosphere
450
00:34:21,000 --> 00:34:25,143
they create a spray of particles
of the opposite charge.
451
00:34:35,220 --> 00:34:37,500
If we can't capture anti-matter particles
452
00:34:37,500 --> 00:34:41,813
in orbit we may find a way
to produce them on Earth.
453
00:34:49,885 --> 00:34:52,385
(light music)
454
00:34:54,360 --> 00:34:57,986
Down at CERN, the giant physics
lab on the border of France
455
00:34:57,986 --> 00:35:02,250
and Switzerland, scientists
have been creating anti-matter
456
00:35:02,250 --> 00:35:05,823
as a way of studying the
underlying nature of our universe,
457
00:35:06,712 --> 00:35:10,383
and how it emerged in the
earliest moments of time.
458
00:35:12,240 --> 00:35:14,820
Using the Large Hadron Collider,
459
00:35:14,820 --> 00:35:17,710
they accelerate atoms to
nearly the speed of light
460
00:35:20,340 --> 00:35:22,140
and blast them together
461
00:35:22,140 --> 00:35:24,543
to release their fundamental constituents.
462
00:35:30,210 --> 00:35:33,660
But the anti-matter yield
is so small that the cost
463
00:35:33,660 --> 00:35:37,290
of producing just a
gram's worth is estimated
464
00:35:37,290 --> 00:35:39,843
to be upwards of $100 trillion,
465
00:35:43,200 --> 00:35:45,720
and the stuff is so volatile
466
00:35:45,720 --> 00:35:48,630
that storing more than
a few atoms at a time
467
00:35:48,630 --> 00:35:50,883
remains a significant challenge.
468
00:35:53,430 --> 00:35:56,820
Our ability to produce
such an energy dense fuel
469
00:35:56,820 --> 00:35:58,470
raises basic questions
470
00:35:58,470 --> 00:36:01,383
about whether interstellar
flight is even possible.
471
00:36:12,210 --> 00:36:13,740
One thing's for sure,
472
00:36:13,740 --> 00:36:16,803
more Earth-friendly
alternatives such as geothermal,
473
00:36:18,570 --> 00:36:23,022
solar and wind won't transform us
474
00:36:23,022 --> 00:36:26,280
into a planetary civilization,
475
00:36:26,280 --> 00:36:29,820
and they simply don't pack
enough explosive power
476
00:36:29,820 --> 00:36:31,623
to get us to Proxima Centauri.
477
00:36:34,290 --> 00:36:36,960
Anti-matter might, provided we can learn
478
00:36:36,960 --> 00:36:39,963
to control and produce
it in enough quantity.
479
00:36:42,270 --> 00:36:45,690
It is the most powerful fuel known,
480
00:36:45,690 --> 00:36:48,090
with about two billion times more energy
481
00:36:48,090 --> 00:36:50,733
per volume than conventional rocket fuel.
482
00:36:53,130 --> 00:36:56,010
In contemporary spacecraft designs,
483
00:36:56,010 --> 00:37:00,813
protons and antiprotons are
isolated with magnetic fields.
484
00:37:05,250 --> 00:37:07,230
They're channeled in parallel
485
00:37:07,230 --> 00:37:08,493
to a propulsion chamber.
486
00:37:15,630 --> 00:37:19,173
Where they collide the
streams annihilate each other.
487
00:37:23,083 --> 00:37:26,880
The blast creates a high energy beam
488
00:37:26,880 --> 00:37:30,870
that pushes on a magnetic
field within the crack.
489
00:37:30,870 --> 00:37:32,433
Accelerating it forward.
490
00:37:36,420 --> 00:37:37,650
Though it would take only
491
00:37:37,650 --> 00:37:40,690
a thousandth of a gram to fly to Saturn
492
00:37:42,390 --> 00:37:45,450
the craft would need to carry tons more
493
00:37:45,450 --> 00:37:47,940
to get up to interstellar speeds
494
00:37:47,940 --> 00:37:50,853
and reach Proxima Centauri
within a human lifetime.
495
00:37:54,090 --> 00:37:58,110
Such a potent fuel brings serious hazards.
496
00:37:58,110 --> 00:37:59,610
The high temperatures produced
497
00:37:59,610 --> 00:38:01,500
by an anti-matter engine
498
00:38:01,500 --> 00:38:04,353
would be enough to destroy the spacecraft.
499
00:38:06,420 --> 00:38:08,380
It would have to be made of materials
500
00:38:08,380 --> 00:38:12,387
not yet invented that can
radiate that heat into space.
501
00:38:12,387 --> 00:38:14,970
(upbeat music)
502
00:38:22,530 --> 00:38:24,063
Setting out on its journey,
503
00:38:24,930 --> 00:38:26,880
the spacecraft must navigate
504
00:38:26,880 --> 00:38:29,463
an obstacle course of
interstellar objects.
505
00:38:39,240 --> 00:38:42,300
If it meets a meteor, it uses a battery
506
00:38:42,300 --> 00:38:45,103
of shields to pulverize the object.
507
00:38:45,103 --> 00:38:47,520
(loud booms)
508
00:38:49,800 --> 00:38:50,943
And whisk it away.
509
00:38:59,490 --> 00:39:02,370
If the craft plows through a cloud of dust
510
00:39:02,370 --> 00:39:04,983
it's buffered by a
protective magnetic field.
511
00:39:17,850 --> 00:39:22,850
As it finally closes in on its
target, it releases a probe.
512
00:39:23,430 --> 00:39:25,233
Our cosmic envoy,
513
00:39:29,340 --> 00:39:32,130
powered by its own anti-matter engine,
514
00:39:32,130 --> 00:39:35,340
firing in reverse, the probe would need
515
00:39:35,340 --> 00:39:39,423
to spend years even decades slowing down.
516
00:39:48,780 --> 00:39:50,910
Even at these speeds,
517
00:39:50,910 --> 00:39:53,130
the mission is probably too long
518
00:39:53,130 --> 00:39:55,513
for any human to go along.
519
00:39:55,513 --> 00:39:58,263
(dramatic music)
520
00:40:24,840 --> 00:40:26,340
Imagine for a moment,
521
00:40:26,340 --> 00:40:28,980
a future in which time and distance
522
00:40:28,980 --> 00:40:32,310
are not so daunting, and the stars
523
00:40:32,310 --> 00:40:34,443
are literally at our fingertips.
524
00:40:38,224 --> 00:40:40,807
(upbeat music)
525
00:40:51,540 --> 00:40:53,160
The spacecraft maneuvers
526
00:40:53,160 --> 00:40:57,483
into an orbital station
in preparation for launch.
527
00:41:05,220 --> 00:41:07,530
It's a testament to science conceived
528
00:41:07,530 --> 00:41:09,880
on a stunning theoretical frontier
529
00:41:11,280 --> 00:41:14,613
with engineering far
beyond what we know today.
530
00:41:29,100 --> 00:41:32,160
This craft is based on a
mind boggling discovery
531
00:41:32,160 --> 00:41:36,720
by Albert Einstein that gravity
532
00:41:36,720 --> 00:41:40,623
is the distortion of
space by massive objects.
533
00:41:49,110 --> 00:41:52,710
What if a spaceship could
manipulate this strange cosmic
534
00:41:52,710 --> 00:41:56,823
trait to pass between the
folds of space and time?
535
00:42:00,300 --> 00:42:03,120
Such a spacecraft would
run on exotic forms
536
00:42:03,120 --> 00:42:08,120
of matter not yet discovered,
and use the equivalent
537
00:42:08,130 --> 00:42:12,093
of all the electric power
generated by the United States.
538
00:42:16,560 --> 00:42:20,433
Welcome to Warp Drive.
539
00:42:24,420 --> 00:42:27,430
In theory, this ship
could go faster than light
540
00:42:28,800 --> 00:42:31,923
as it traverses the
galaxy in a cosmic bubble.
541
00:42:35,990 --> 00:42:38,700
But don't book your flight just yet,
542
00:42:38,700 --> 00:42:41,190
building a spacecraft like this will take
543
00:42:41,190 --> 00:42:44,163
breathtaking advances in
science and technology.
544
00:42:46,680 --> 00:42:48,820
As far off as this may be,
545
00:42:48,820 --> 00:42:51,526
who can say what
challenges human ingenuity
546
00:42:51,526 --> 00:42:53,970
will one day overcome,
547
00:42:53,970 --> 00:42:58,630
what ideas or technologies
will propel us forward.
548
00:42:59,737 --> 00:43:02,237
(light music)
549
00:43:08,430 --> 00:43:12,510
when, or if, we do reach for the stars,
550
00:43:12,510 --> 00:43:15,300
the impulse will no doubt come not
551
00:43:15,300 --> 00:43:17,283
from a struggle to survive,
552
00:43:18,170 --> 00:43:20,710
but from a sense of wonder
553
00:43:21,840 --> 00:43:24,993
at the limitless variety
of a living universe.
554
00:43:38,160 --> 00:43:42,390
The scene is hundreds or
thousands of years in the future,
555
00:43:42,390 --> 00:43:46,593
a Starship arrives at Proxima
B or a similar destination.
556
00:43:56,460 --> 00:43:59,730
Whether the craft carries humans or not,
557
00:43:59,730 --> 00:44:02,310
we'll likely send an unmanned probe down
558
00:44:02,310 --> 00:44:04,653
to give us our first up close look.
559
00:44:05,695 --> 00:44:08,362
(upbeat music)
560
00:44:33,150 --> 00:44:35,250
It may well land using technologies
561
00:44:35,250 --> 00:44:36,783
we've perfected in our day.
562
00:44:38,400 --> 00:44:40,593
At the dawn of planetary exploration.
563
00:45:11,670 --> 00:45:14,283
Sensors will probe the alien landscape.
564
00:45:19,980 --> 00:45:21,960
Artificial intelligence that evolved
565
00:45:21,960 --> 00:45:25,203
and was updated during the
journey will interpret the scene.
566
00:45:28,740 --> 00:45:30,903
What's the makeup of the planet's soil?
567
00:45:31,890 --> 00:45:32,943
It's atmosphere.
568
00:45:34,530 --> 00:45:36,693
Has life established a foothold?
569
00:45:40,050 --> 00:45:44,613
Steadily a new world
surrenders its secrets.
570
00:45:46,800 --> 00:45:50,070
With each revelation we reflect
571
00:45:50,070 --> 00:45:52,893
on the odyssey that brought us here,
572
00:45:54,990 --> 00:45:58,200
and how it began in the discoveries
573
00:45:58,200 --> 00:46:02,970
and dreams of generations long past.
574
00:46:08,633 --> 00:46:11,216
(upbeat music)
575
00:46:47,497 --> 00:46:50,914
(upbeat music continues)
44548
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