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... a small piece of space -they call it junk- had been
causing a big headache for NASA scientists ...
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Houston is monitoring a piece of debris that could possibly
pass in front of the International Space Station's orbit ...
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... talking about this 6" square piece ...
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... of it colliding with the International Space Station is
within the red threshold. There is not enough time ...
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... to seek shelter ...
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... travelling at 17.000 miles an hour ...
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... if it were to hit the space station ...
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... could do a little damage ...
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... could really cause a very bad day ...
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... 6, 5, 4, 3, 2, 1, 0 ...
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The eagle has landed.
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It's one small step for man, one giant leap for mankind.
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After half a century of space exploration, we're now suddenly
faced with what's long been a staple of science fiction:
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an orbiting junkyard of cast-off space debris.
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The American southwest is a breathtaking testament
to the forces of nature that have shaped our world.
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OK. We're comin' up on it now.
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This is Meteor Crater near Winslow, Arizona.
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It is considered the world's best preserved meteorite impact site.
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Meet Donald Kessler, retired head of orbital debris at NASA.
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His guide, Eduardo Gonzales...
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A 16-year veteran of Meteor Crater and a man who
shares Kessler's passion for the wonders of the universe...
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So Don, how was your ride up here?
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Oh, it was wonderful! It was like landing on the moon!
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But we're on earth! Can you believe it?
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At Meteor Crater, they always find common ground.
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... result of a collision from the Asteroid Belt
that happened 50.000 years ago ...
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For Don, this place brings some of the science of orbital debris to life in a big way.
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Follow me and I'll show you.
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Nearly 1 mile across, 2.5 miles around and 550 feet deep,
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Meteor Crater is the astounding outcome of a nickel-iron meteorite
hitting earth with the energy of more than 20 million tonnes of TNT,
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creating all of this in just 10 seconds.
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The fact that this meteorite came from outer space makes me awestruck.
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We're just seeing a small slice of the process that really made the Earth what it is.
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It's a sobering reminder of the incredible collisions
that occur throughout the universe,
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from meteor impacts like this one to the collision of entire galaxies.
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Throughout time, space collisions have occurred as part of the natural process.
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Scientist believe that billions of years from now, our own
Milky Way galaxy and its closest neighbour, the Andromeda Spiral Galaxy,
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could collide and merge to create a new giant elliptical galaxy,
spewing stars along the way.
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Incredible...
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Collisions like this have forever played a major role
in the creation and formation of our own Solar System.
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It's this natural process that concerned Kessler over 30 years ago.
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Kessler's question was: If all of these collisions are occurring in nature,
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what�s going to happen to all of the
man-made objects we're putting into space?
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At the time, Kessler's thinking did not align with popular beliefs.
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Ever since human ventured into space,
we've embraced the Big Sky Theory.
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The theory holds that the space is so big, you could launch
anything into orbit and it wouldn't collide with anything else.
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But it turns out that space is smaller than we thought.
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Low-Earth Orbit, or LEO as it's called, is home to the International Space Station,
the Hubble Telescope and most of our satellites.
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In Middle-Earth Orbit, we find GPS and weather satellites.
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Geosynchronous Orbit, or GEO, the orbit farthest away from the Earth,
is crowded with communication satellites.
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With so many objects careening through the same altitudes,
it's not hard to imagine that some may eventually collide.
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Known as the Kessler Syndrome, Kessler's prediction stated that
random collisions between man-made objects
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would create smaller debris that would become
increasingly hazardous to spacecraft.
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The resulting chain reaction would create exponentially expanding clouds of debris.
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Even if we don't launch anything else into space, this orbiting belt of debris
could very well alter space exploration as we know it.
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Is it possible that we're now at the tipping point of
this cascading, uncontrollable event?
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Alarmingly, in the three decades since Donald Kessler's prediction,
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the amount of debris in Low-Earth and Geosynchronous Orbit has grown
at a rapidly expanding rate into a minefield of discarded trash.
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In the past,
most of the small particles came from the bigger objects falling apart.
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In the future, and we're reaching that threshold right now,
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the objects are gonna come random collisions,
just like in the Solar System.
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Just like our one Sun-spoiled ecosystems here on earth,
our orbits are becoming increasingly endangered.
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From space exploration to satellite communication,
humans have developed a profound connection to space.
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What would happen if it were all to suddenly go away?
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Launched in 1993, Cosmos 2251 provides communication
for Russian military and intelligence forces from Low-Earth Orbit.
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Satellites like this are part of what's called "a constellation,"
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a grouping of satellites spread out in a set of orbital rings
providing an uninterrupted stream of communications,
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with each rotation in as little as 90 minutes.
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These and thousands of other satellites orbit earth 16 times per day.
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The gravitational pull from nearby earth is so strong,
every satellite has to travel at hyper-velocity speeds,
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upwards of 17.000 miles per hour.
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The pull of gravity, balanced against the satellite's velocity,
creates this curved orbital path.
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Satellites and their around-the-clock services are a fact of modern life.
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LEO is ideal for communication satellites like Iridium 33,
which provides voice and data coverage for cellular telephones.
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With satellites like Cosmos and Iridium constantly crossing each other's paths,
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they often experience what satellite operators refer to as "close approaches",
two satellites passing within just a few short miles of one another.
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Amazingly, that can happen around 150 times a day.
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Space is indeed a busy place.
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Our planet's need for communication has transformed what was once called
"the Final Frontier" into something far less romantic and far more congested.
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Just 50 years ago, the boundary seemed limitless.
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From a ground station nestled in the mountains of Andover, Maine,
a signal is sent to a speeding satellite.
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An historic feat, that could reshape man's future...
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That satellite of course is the Telstar.
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170 pounds of messages and computer data
all can be handled by the orbiting device.
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Ironically, this technological wonder dies one year later,
becoming as what is known as a "zombie satellite."
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Telstar began the revolution in communications
that now features a fleet of satellites in the region we know as GEO.
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These satellites form a densely populated belt that circles the Equator.
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They facilitate most of the world's television,
military and internet communications.
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Because its orbit mirrors earth's rotation,
a satellite will appear to hover over a point on the earth's surface.
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The result? 24/7 continuous coverage from air to sea, to land...
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Think about this:
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Here on earth when you download a music file, host a video,
tweet, friend someone, or watch your favourite cable TV show,
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it's coming from GEO.
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Our busy lives on earth have become deeply connected to space.
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Just like a coral reef or a rainforest, GEO is a limited natural resource.
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There's only one spot in GEO for each satellite to maintain position.
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Satellites may drift due to gravitational pull from both
the Sun and the Moon, slowly changing their orbits.
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Enter station keepers, traffic cops of space...
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They send signals commanding satellites to adjust orbits,
by firing up the onboard thrusters,
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keeping them out of harm's way.
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But no amount of station keeping would have altered the course of
what was to become the largest debris-generating event on record.
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In early 2007, an anti-satellite missile test took place in LEO.
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Its target? A dead weather satellite...
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In less than 24 hours, the debris encircled the earth,
hovering at the original impact altitude of over 500 miles,
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high enough so that the pieces won't come down,
but low enough so that they have the potential to affect almost all other objects in Low-Earth Orbit,
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including the International Space Station.
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Today, as the debris cloud keeps growing, so does our understanding of it.
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The majority of debris from this one event
will remain a hazard in our skies for centuries to come.
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This visualisation shows the formation of one of the first galaxies,
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massive stars filling the universe with light,
beginning when it was 300 million years old,
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and continuing up to its present age of 13.7 billion years.
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It's an awe-inspiring look at the lifespan of the universe,
with galaxies forming, and naturally colliding...
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Ultimately spinning the massive thread-like structure of the cosmic web...
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At Lowell Observatory,
Don Kessler is guided by Kim Herman, post-doctoral associate.
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Arizona's known for its observatories,
and fortunately very close to Meteor Crater is Lowell.
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All my life I've been interested in astronomy.
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I've visited several observatories that were designed
for the purpose of looking at satellites, but never one with astronomy.
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Here astronomers are well-connected to the stars.
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Bordered by a ponderosa pine forest 8.000 feet up,
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elevation and absolute isolation create a pristine sky
for professional and amateur astronomers of all ages.
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The night sky here opens up infinite possibilities for the naked eye.
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Here the sky is so clear, gets so dark that we don't
even need telescopes to see what's going on in the sky.
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Eyum is using her smartphone to stargaze
and know what she's looking at.
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And over there Saturn should be coming out.
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When I think about Saturn's beautiful rings,
I think of collisions in space and what earth could look like millions of years from now.
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Overtime, collisions would create more debris and in turn even more collisions.
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Gradually, the debris would shrink in size and speeds would slow until finally
the Earth would be surrounded by stable, Saturn-like rings.
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When I look at the night sky the first thing I notice is stars.
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The beauty of the universe is striking to me.
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The next thing I'll notice is meteors.
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If I see a meteor I feel like I'm lucky,
because that also reminds me of these particles passing through space.
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Then I may notice something flickering and moving
and realise that I'm looking at a satellite orbiting the Earth.
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Those satellites are there because we put them there.
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And I may see another one, travelling in the opposite direction.
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It could collide with the first one;
their paths do cross.
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An astronaut was asked this question:
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When you're in orbit and see these things in space,
does that worry you?
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His answer was: I worry more about what I don't see.
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Our belief that what goes up must come down isn't always true.
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It's estimated that LEO contains 6000 tonnes of space junk,
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and GEO is home to 400 dead satellites,
parked into a higher graveyard orbit,
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where they will remain for hundreds of years.
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That's a whole lot of junk.
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So what exactly is out there?
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Over the last 50 years, we've launched several thousand objects into space.
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Yet there are only around 1000 spacecraft that are operational at this time.
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What may surprise many people is that
once and object stops functioning, we leave it in orbit.
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Every single one of these non-operational spacecrafts is a potential source of debris.
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In fact, most spacecrafts that are launched into the orbit
actually leave a trail of debris in the process.
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Upper-stage rocket bodies weighing several tonnes
make up a good portion of junk in space.
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... as do mission-related objects like cast-off bolts, or o-rings ...
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The rest, of miscellaneous fragments, exploded rockets, left-over fuel...
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And the list goes on...
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But even with this incredible amount of debris,
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few people were taking the notion of space junk seriously
until the morning of February 10, 2009.
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Earlier that day, a report was issued predicting that
Iridium 33 would encounter a close approach of just 1900 feet
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with another spacecraft.
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It's Cosmos 2251, travelling at the same speed as Iridium.
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Amazingly, this collision alert wasn't even among the top predicted
for any of the Iridium satellites for the coming week.
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But at 4:56 PM, the time predicted for the close approach,
Iridium 33 went silent.
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Two satellites that had simultaneously circled the planet for a dozen years
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had collided.
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Cosmos, as it turned out, was a dead satellite,
ceasing to function in 1995, just two years after it was launched.
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Now more than a 100.000 pieces from this collision cloud Low-Earth Orbit.
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The Iridium-Cosmos collision was very much a game changer.
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There were those who thought of space in terms of a Big Sky Theory,
that it was limitless and we didn't need to worry about ever crowding it.
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It became very obvious that that wasn't true and people began to consider:
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What do we need to do to keep this from happening again?
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Far from space, deep in the desert near White Sands, New Mexico,
sits the remote hyper-velocity test laboratory,
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where engineers are providing solutions required to advance
space travel in the face of these gathering obstacles.
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Scientists analyze what we can only imagine:
hyper-velocity impacts,
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collisions between objects travelling at speeds of up to 15.000 miles per hour.
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These scientific visualisations show a fragment no bigger than a beebee
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blasting through an aluminium plate,
typically used to protect spacecraft.
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Even the smallest of impacts scatter debris,
delivering wide-spread damage.
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Whether it's a circuit board or a wayward bolt, or even the tiniest chip of paint,
orbital debris travelling at these speeds poses a very real threat.
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Because of this, the International Space Station features extra shielding,
as shown in red, over the areas most likely to be hit.
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To further protect the ISS, its orbit is monitored within what is referred to as a "pizza box,"
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creating a safe zone on all sides to help keep it out of harm's way.
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That's the job of the US Space Surveillance Network,
where they detect and catalogue man-made objects.
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Utilising a vast array of RADARs and sensors,
we're able to track thousands of pieces of space junk larger than a softball.
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Some of them, like rocket boosters, are the size of a school bus.
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But what's far more troubling is all the debris that can't be tracked.
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Debris the size of marbles, among them waste from
rocket propellant and fragments from collisions,
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is capable of inflicting lethal damage.
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Millions of particles the size of darts are far beyond detection.
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But the craters they produce on spacecraft are well-documented.
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Most importantly, the network charts the orbital paths of
the catalogued debris and issues collision alerts to station keepers.
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So where do we go from here?
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Forces of nature and natural collisions will continue to shape our universe.
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But man-made collisions?
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Perhaps those we can do something about...
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The good news is that people have begun to come up with new ideas
to bring back the pristine environment that we would like space to be.
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Scientists and engineers are developing breakthrough innovations
to help us begin cleaning up space someday soon.
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The question is: How do we catch up to and capture debris
tumbling through Low-Earth Orbit at thousands of miles an hour?
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And then, how do we slow it down,
so that it falls out of orbit and burns up in the atmosphere?
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One fascinating concept involves the use of electro-dynamic tether,
which would deal with the spacecraft by generating drag,
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through interactions between currents in the tether and the Earth's magnetic field.
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This increased drag would lower the spacecraft out of orbit
until it re-enters the atmosphere and burns up.
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We may also be able to capture debris with a net.
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Japan's Space Agency has been working with a fishing net manufacturer
to look at creating a "space fishing net," which, like the tether,
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could be powered using the earth's magnetosphere.
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Imagine that...
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A centuries-old fishing tool might just become
a brand-new tool for cleaning up space.
205
00:31:12,457 --> 00:31:21,055
Lasers could one day sweep space, striking smaller objects,
slowing them down and causing them to tumble into the atmosphere.
206
00:31:33,410 --> 00:31:41,524
Solar sails could someday be part of the satellites we launch,
helping them to de-orbit once their work in space is done.
207
00:31:41,525 --> 00:31:52,689
Space-faring nations are now working to develop sustainable methods
to explore space and new technology to reclaim what has been left in orbit.
208
00:31:58,066 --> 00:32:07,337
As we continue to launch our dreams into space,
what if one day objects in space were located and captured by a garbage vehicle?
209
00:32:20,222 --> 00:32:24,115
The vehicle could then dock at a recycling facility,
210
00:32:24,116 --> 00:32:30,767
a place where space debris could be stored and recycled to create new parts.
211
00:32:36,324 --> 00:32:37,375
Imagine...
212
00:32:37,376 --> 00:32:46,040
Aluminium and fuel from centuries old upper-stage rockets
recovered and poured into an industrial outer space post...
213
00:32:54,731 --> 00:32:57,997
Industrialising space is never and issue of science fiction.
214
00:32:57,998 --> 00:33:04,386
It's more of a question of do we want to do it and
when do we have the infrastructure established so that we can do it.
215
00:33:05,384 --> 00:33:09,014
It's work we will do in the future as move out into space.
216
00:33:11,353 --> 00:33:20,218
Space-based recycling could someday become a reality,
launching a new, greener era of space exploration.
217
00:33:28,998 --> 00:33:36,661
For as long as humans have walked the planet,
we've looked at the heavens to help us define our role in the universe.
218
00:33:36,942 --> 00:33:46,631
The celestial bodies in our skies and the constellations they form
have forever shaped our notions of time and place.
219
00:33:46,632 --> 00:33:51,669
Today, constellations of our own making fill the night skies
220
00:33:51,670 --> 00:33:57,275
as we continue to push skyward,
relying on what the universe has taught us.
221
00:33:57,276 --> 00:34:02,386
Where would we be, if we couldn't consult the stars?
222
00:34:06,800 --> 00:34:13,254
Growing up, it was my fantasy that I would get to see humanity
spread off of the Earth and throughout the Solar System.
223
00:34:13,255 --> 00:34:16,978
So do I think this snowballing event will actually happen?
224
00:34:16,979 --> 00:34:23,333
I can't imagine after dreaming and working toward space flight
and after 50 years of having achieved it,
225
00:34:23,334 --> 00:34:26,011
that we would ever cut ourselves off from space.
226
00:34:26,012 --> 00:34:31,000
That does against everything that humanity has ever strived for.
227
00:34:31,001 --> 00:34:35,734
My legacy will probably always include
being knows as the father of "space junk."
228
00:34:35,735 --> 00:34:44,551
What I hope that means is that we continue to maintain access
to space and learn more about life and the environment.
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