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...a small piece of
space--they call it junk
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--had been causing a big
headache for NASA scientists...
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00:00:38,385 --> 00:00:42,345
Houston is monitoring a piece
of debris that could possibly
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00:00:42,346 --> 00:00:45,506
pass in front of the International
Space Station's orbit...
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00:00:45,507 --> 00:00:47,567
...talking about this
6" square piece...
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00:00:48,702 --> 00:00:51,374
...of it colliding with the
International Space Station
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is within the red threshold.
There is not enough time...
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00:00:55,047 --> 00:00:56,328
...to seek shelter...
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00:00:58,210 --> 00:01:00,993
...travelling at
17,000 miles an hour...
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00:01:00,994 --> 00:01:03,897
...if it were to hit
the space station...
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00:01:03,898 --> 00:01:04,983
...could do a little damage...
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00:01:04,984 --> 00:01:05,984
...could really cause
a very bad day...
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00:01:12,646 --> 00:01:21,281
...6, 5, 4, 3, 2, 1, 0...
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00:01:44,141 --> 00:01:45,430
The eagle has landed.
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00:01:48,107 --> 00:01:53,109
It's one small step for man,
one giant leap for mankind.
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00:01:54,746 --> 00:01:57,801
After half a century
of space exploration,
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00:01:58,302 --> 00:02:04,657
we're now suddenly faced with what's
long been a staple of science fiction:
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00:02:04,658 --> 00:02:08,797
an orbiting junkyard of
cast-off space debris.
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00:02:35,207 --> 00:02:38,575
The American southwest is
a breathtaking testament
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00:02:38,576 --> 00:02:41,944
to the forces of nature
that have shaped our world.
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00:02:50,741 --> 00:02:53,554
OK. We're comin' up on it now.
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00:02:56,021 --> 00:02:59,400
This is Meteor Crater
near Winslow, Arizona.
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00:02:59,401 --> 00:03:03,951
It is considered the world's best
preserved meteorite impact site.
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00:03:40,800 --> 00:03:45,392
Meet Donald Kessler, retired
head of orbital debris at NASA.
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00:03:46,110 --> 00:03:48,550
His guide, Eduardo Gonzales...
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00:03:48,551 --> 00:03:52,564
A 16-year veteran of Meteor
Crater and a man who shares
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00:03:52,565 --> 00:03:55,577
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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00:04:11,450 --> 00:04:14,084
For Don, this place
brings some of the science
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00:04:14,085 --> 00:04:17,807
of orbital debris to life in a big way.
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00:04:17,808 --> 00:04:19,525
Follow me and I'll show you.
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00:04:25,827 --> 00:04:33,309
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
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hitting earth with the energy of
more than 20 million tonnes of TNT,
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00:04:43,263 --> 00:04:47,673
creating all of this in just 10 seconds.
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00:05:33,500 --> 00:05:38,591
The fact that this meteorite came
from outer space makes me awestruck.
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00:05:40,650 --> 00:05:43,321
We're just seeing a
small slice of the process
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00:05:43,322 --> 00:05:45,404
that really made the Earth what it is.
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00:05:56,836 --> 00:05:59,616
It's a sobering reminder
of the incredible collisions
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that occur throughout the universe,
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00:06:01,471 --> 00:06:07,384
from meteor impacts like this one
to the collision of entire galaxies.
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00:06:19,177 --> 00:06:24,610
Throughout time, space collisions have
occurred as part of the natural process.
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00:06:25,946 --> 00:06:29,364
Scientist believe that
billions of years from now,
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00:06:29,365 --> 00:06:34,582
our own Milky Way galaxy and its closest
neighbour, the Andromeda Spiral Galaxy,
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00:06:34,583 --> 00:06:40,150
could collide and merge to create
a new giant elliptical galaxy,
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00:06:40,151 --> 00:06:42,918
spewing stars along the way.
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00:06:43,650 --> 00:06:44,666
Incredible...
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00:07:12,050 --> 00:07:15,488
Collisions like this have
forever played a major role
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00:07:15,489 --> 00:07:18,926
in the creation and formation
of our own Solar System.
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00:07:18,927 --> 00:07:24,416
It's this natural process that
concerned Kessler over 30 years ago.
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00:07:35,300 --> 00:07:39,918
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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00:07:49,050 --> 00:07:53,280
At the time, Kessler's thinking
did not align with popular beliefs.
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00:07:53,550 --> 00:07:59,339
Ever since human ventured into space,
we've embraced the Big Sky Theory.
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00:08:01,006 --> 00:08:03,897
The theory holds that
the space is so big,
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00:08:03,898 --> 00:08:08,788
you could launch anything into orbit and
it wouldn't collide with anything else.
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00:08:09,200 --> 00:08:12,299
But it turns out that space
is smaller than we thought.
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00:08:12,300 --> 00:08:17,410
Low-Earth Orbit, or LEO as it's called,
is home to the International Space Station,
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00:08:17,411 --> 00:08:20,321
the Hubble Telescope and
most of our satellites.
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00:08:22,050 --> 00:08:26,325
In Middle-Earth Orbit, we find
GPS and weather satellites.
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00:08:37,450 --> 00:08:42,875
Geosynchronous Orbit, or GEO, the
orbit farthest away from the Earth,
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is crowded with
communication satellites.
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00:08:48,700 --> 00:08:51,826
With so many objects careening
through the same altitudes,
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00:08:51,827 --> 00:08:56,353
it's not hard to imagine that
some may eventually collide.
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00:09:07,100 --> 00:09:10,650
Known as the Kessler
Syndrome, Kessler's prediction
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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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00:09:30,950 --> 00:09:33,859
Even if we don't launch
anything else into space,
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this orbiting belt of debris could very
well alter space exploration as we know it.
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00:09:44,850 --> 00:09:47,617
Is it possible that we're
now at the tipping point
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00:09:47,618 --> 00:09:51,385
of this cascading, uncontrollable event?
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00:09:55,400 --> 00:09:59,808
Alarmingly, in the three decades
since Donald Kessler's prediction,
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00:09:59,809 --> 00:10:03,684
the amount of debris in
Low-Earth and Geosynchronous Orbit
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has grown at a rapidly expanding rate
into a minefield of discarded trash.
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00:10:13,650 --> 00:10:19,889
In the past, most of the small particles
came from the bigger objects falling apart.
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00:10:19,890 --> 00:10:23,483
In the future, and we're
reaching that threshold right now,
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00:10:23,484 --> 00:10:28,758
the objects are gonna come random
collisions, just like in the Solar System.
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00:10:30,550 --> 00:10:33,979
Just like our one Sun-spoiled
ecosystems here on earth,
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our orbits are becoming
increasingly endangered.
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00:10:37,409 --> 00:10:41,291
From space exploration to
satellite communication,
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00:10:41,292 --> 00:10:44,773
humans have developed a
profound connection to space.
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00:10:44,774 --> 00:10:48,661
What would happen if it
were all to suddenly go away?
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00:10:49,550 --> 00:10:54,680
Launched in 1993, Cosmos
2251 provides communications
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00:10:54,681 --> 00:10:59,810
for Russian military and intelligence
forces from Low-Earth Orbit.
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00:10:59,811 --> 00:11:04,599
Satellites like this are part of
what's called "a constellation,"
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00:11:04,600 --> 00:11:08,967
a grouping of satellites spread
out in a set of orbital rings
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00:11:08,968 --> 00:11:12,934
providing an uninterrupted
stream of communications,
93
00:11:12,935 --> 00:11:15,978
with each rotation in
as little as 90 minutes.
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00:11:15,979 --> 00:11:22,432
These and thousands of other
satellites orbit earth 16 times per day.
95
00:11:24,450 --> 00:11:28,476
The gravitational pull from
nearby earth is so strong,
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00:11:28,477 --> 00:11:32,502
every satellite has to travel
at hyper-velocity speeds,
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00:11:32,503 --> 00:11:35,789
upwards of 17,000 miles per hour.
98
00:11:35,790 --> 00:11:39,531
The pull of gravity, balanced
against the satellite's velocity,
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00:11:39,532 --> 00:11:43,272
creates this curved orbital path.
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00:11:54,200 --> 00:11:59,400
Satellites and their around-the-clock
services are a fact of modern life.
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00:12:01,400 --> 00:12:06,500
LEO is ideal for communication
satellites like Iridium 33,
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00:12:06,501 --> 00:12:10,600
which provides voice and data
coverage for cellular telephones.
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00:12:13,600 --> 00:12:18,426
With satellites like Cosmos and Iridium
constantly crossing each other's paths,
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00:12:18,427 --> 00:12:24,645
they often experience what satellite
operators refer to as "close approaches",
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two satellites passing within just
a few short miles of one another.
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00:12:29,065 --> 00:12:33,912
Amazingly, that can happen
around 150 times a day.
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00:12:33,913 --> 00:12:37,183
Space is indeed a busy place.
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00:12:42,800 --> 00:12:47,914
Our planet's need for communication
has transformed what was once called
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"the Final Frontier" into something far
less romantic and far more congested.
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00:12:55,050 --> 00:12:59,537
Just 50 years ago, the
boundary seemed limitless.
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00:13:04,450 --> 00:13:07,687
From a ground station nestled in
the mountains of Andover, Maine,
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00:13:07,688 --> 00:13:10,324
a signal is sent to
a speeding satellite.
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00:13:10,325 --> 00:13:13,793
An historic feat, that
could reshape man's future...
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00:13:13,794 --> 00:13:16,889
That satellite of course is the Telstar.
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00:13:16,890 --> 00:13:22,538
170 pounds of messages and computer data
all can be handled by the orbiting device.
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00:13:23,400 --> 00:13:27,580
Ironically, this technological
wonder dies one year later,
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becoming as what is known
as a "zombie satellite."
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Telstar began the
revolution in communications
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00:13:37,686 --> 00:13:42,370
that now features a fleet of
satellites in the region we know as GEO.
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00:13:43,100 --> 00:13:48,055
These satellites form a densely
populated belt that circles the Equator.
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00:13:55,600 --> 00:13:58,325
They facilitate most of
the world's television,
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00:13:58,326 --> 00:14:01,378
military and internet communications.
123
00:14:01,379 --> 00:14:04,309
Because its orbit
mirrors earth's rotation,
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00:14:04,310 --> 00:14:08,640
a satellite will appear to hover
over a point on the earth's surface.
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00:14:09,300 --> 00:14:15,829
The result? 24/7 continuous
coverage from air to sea, to land...
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00:14:21,650 --> 00:14:22,892
Think about this:
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00:14:22,893 --> 00:14:27,207
Here on earth when you download
a music file, host a video,
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00:14:27,208 --> 00:14:31,521
tweet, friend someone, or watch
your favourite cable TV show,
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00:14:31,522 --> 00:14:33,245
it's coming from GEO.
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00:14:41,550 --> 00:14:46,860
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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00:14:59,446 --> 00:15:04,230
There's only one spot in GEO for
each satellite to maintain position.
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00:15:04,231 --> 00:15:08,133
Satellites may drift due
to gravitational pull from
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00:15:08,134 --> 00:15:12,235
both the Sun and the Moon,
slowly changing their orbits.
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00:15:12,236 --> 00:15:17,275
Enter station keepers,
traffic cops of space...
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00:15:17,276 --> 00:15:21,009
They send signals commanding
satellites to adjust orbits,
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00:15:21,010 --> 00:15:23,342
by firing up the onboard thrusters,
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00:15:23,343 --> 00:15:25,668
keeping them out of harm's way.
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00:15:25,669 --> 00:15:29,293
But no amount of station keeping
would have altered the course
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00:15:29,294 --> 00:15:34,318
of what was to become the largest
debris-generating event on record.
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00:15:38,178 --> 00:15:43,729
In early 2007, an anti-satellite
missile test took place in LEO.
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00:15:48,200 --> 00:15:51,698
Its target? A dead weather satellite...
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00:16:23,600 --> 00:16:27,718
In less than 24 hours, the
debris encircled the earth,
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00:16:27,719 --> 00:16:32,036
hovering at the original impact
altitude of over 500 miles,
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00:16:32,037 --> 00:16:36,361
high enough so that the pieces
won't come down, but low enough
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00:16:36,362 --> 00:16:41,886
so that they have the potential to affect
almost all other objects in Low-Earth Orbit,
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00:16:41,887 --> 00:16:45,248
including the
International Space Station.
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00:16:45,800 --> 00:16:51,618
Today, as the debris cloud keeps
growing, so does our understanding of it.
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00:16:51,619 --> 00:16:54,444
The majority of debris
from this one event
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00:16:54,445 --> 00:16:59,269
will remain a hazard in our
skies for centuries to come.
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00:17:13,500 --> 00:17:18,185
This visualisation shows the
formation of one of the first galaxies,
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00:17:18,186 --> 00:17:22,058
massive stars filling
the universe with light,
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00:17:22,059 --> 00:17:25,766
beginning when it was
300 million years old,
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00:17:25,767 --> 00:17:32,606
and continuing up to its present
age of 13.7 billion years.
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00:17:34,800 --> 00:17:38,868
It's an awe-inspiring look at
the lifespan of the universe,
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00:17:38,869 --> 00:17:42,258
with galaxies forming,
and naturally colliding...
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00:17:42,259 --> 00:17:47,859
Ultimately spinning the massive
thread-like structure of the cosmic web...
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00:18:26,300 --> 00:18:32,538
At Lowell Observatory, Don Kessler is guided
by Kim Herman, post-doctoral associate.
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00:18:35,550 --> 00:18:37,874
Arizona's known for
its observatories, and
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00:18:37,875 --> 00:18:41,927
fortunately very close to
Meteor Crater is Lowell.
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00:18:42,800 --> 00:18:45,744
All my life I've been
interested in astronomy.
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00:18:46,550 --> 00:18:50,297
I've visited several
observatories that were designed
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00:18:50,298 --> 00:18:55,031
for the purpose of looking at
satellites, but never one with astronomy.
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00:18:56,500 --> 00:18:59,515
Here astronomers are
well-connected to the stars.
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00:19:08,600 --> 00:19:12,747
Bordered by a ponderosa
pine forest 8,000 feet up,
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00:19:12,748 --> 00:19:17,342
elevation and absolute
isolation create a pristine sky
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00:19:17,343 --> 00:19:21,654
for professional and amateur
astronomers of all ages.
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00:19:31,950 --> 00:19:36,795
The night sky here opens up infinite
possibilities for the naked eye.
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00:19:41,000 --> 00:19:44,499
Here the sky is so clear
and so dark that we don't
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00:19:44,500 --> 00:19:48,128
even need telescopes to see
what's going on in the sky.
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00:19:49,550 --> 00:19:54,235
Eyum is using her smartphone to
stargaze and know what she's looking at.
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00:19:54,236 --> 00:19:57,192
And over there Saturn
should be coming out.
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00:20:01,400 --> 00:20:04,671
When I think about Saturn's
beautiful rings, I think of collisions
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00:20:04,672 --> 00:20:08,439
in space and what earth could look
like millions of years from now.
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00:20:08,440 --> 00:20:14,707
Overtime, collisions would create more
debris and in turn even more collisions.
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00:20:20,300 --> 00:20:26,319
Gradually, the debris would shrink in
size and speeds would slow until finally
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00:20:26,320 --> 00:20:31,243
the Earth would be surrounded
by stable, Saturn-like rings.
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00:20:36,815 --> 00:20:40,260
When I look at the night sky the
first thing I notice is stars.
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00:20:40,261 --> 00:20:43,404
The beauty of the
universe is striking to me.
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00:20:46,300 --> 00:20:49,108
The next thing I'll notice is meteors.
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00:20:49,109 --> 00:20:52,091
If I see a meteor I feel
like I'm lucky, because that
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00:20:52,092 --> 00:20:55,530
also reminds me of these
particles passing through space.
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00:20:56,550 --> 00:20:59,461
Then I may notice something
flickering and moving
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00:20:59,462 --> 00:21:02,525
and realise that I'm looking at
a satellite orbiting the Earth.
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00:21:02,526 --> 00:21:06,107
Those satellites are there
because we put them there.
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00:21:06,108 --> 00:21:09,020
And I may see another one,
travelling in the opposite direction.
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00:21:09,021 --> 00:21:12,596
It could collide with the
first one; their paths do cross.
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00:21:12,597 --> 00:21:15,192
An astronaut was asked this question:
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00:21:15,193 --> 00:21:19,050
When you're in orbit and see these
things in space, does that worry you?
190
00:21:19,051 --> 00:21:22,956
His answer was: I worry
more about what I don't see.
191
00:21:25,900 --> 00:21:30,940
Our belief that what goes up
must come down isn't always true.
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00:21:30,941 --> 00:21:36,330
It's estimated that LEO contains
6000 tonnes of space junk,
193
00:21:36,331 --> 00:21:43,072
and GEO is home to 400 dead satellites,
parked into a higher graveyard orbit,
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00:21:43,073 --> 00:21:45,981
where they will remain
for hundreds of years.
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00:21:45,982 --> 00:21:48,125
That's a whole lot of junk.
196
00:22:01,500 --> 00:22:04,513
So what exactly is out there?
197
00:22:05,600 --> 00:22:10,450
Over the last 50 years, we've launched
several thousand objects into space.
198
00:22:10,451 --> 00:22:15,808
Yet there are only around 1000 spacecraft
that are operational at this time.
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00:22:15,809 --> 00:22:18,464
What may surprise many people is that
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00:22:18,465 --> 00:22:22,555
once an object stops
functioning, we leave it in orbit.
201
00:22:22,556 --> 00:22:29,490
Every single one of these non-operational
spacecraft is a potential source of debris.
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00:22:30,359 --> 00:22:34,390
In fact, most spacecraft that
are launched into the orbit
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00:22:34,391 --> 00:22:37,738
actually leave a trail
of debris in the process.
204
00:22:37,739 --> 00:22:42,252
Upper-stage rocket bodies
weighing several tonnes
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00:22:42,553 --> 00:22:45,952
make up a good portion of junk in space.
206
00:22:53,900 --> 00:22:59,053
...as do mission-related objects
like cast-off bolts, or o-rings...
207
00:23:01,900 --> 00:23:06,965
The rest, of miscellaneous fragments,
exploded rockets, left-over fuel...
208
00:23:06,966 --> 00:23:09,174
And the list goes on...
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00:23:22,300 --> 00:23:25,404
But even with this
incredible amount of debris,
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00:23:25,405 --> 00:23:29,226
few people were taking the
notion of space junk seriously
211
00:23:29,227 --> 00:23:33,207
until the morning of February 10, 2009.
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00:23:36,300 --> 00:23:39,877
Earlier that day, a report
was issued predicting that
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00:23:39,878 --> 00:23:45,059
Iridium 33 would encounter a
close approach of just 1900 feet
214
00:23:45,060 --> 00:23:47,068
with another spacecraft.
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00:23:51,949 --> 00:23:58,278
It's Cosmos 2251, travelling
at the same speed as Iridium.
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00:24:00,000 --> 00:24:03,319
Amazingly, this collision
alert wasn't even among the top
217
00:24:03,320 --> 00:24:07,039
predicted for any of the Iridium
satellites for the coming week.
218
00:24:08,784 --> 00:24:17,718
But at 4:56 PM, the time predicted for
the close approach, Iridium 33 went silent.
219
00:24:32,300 --> 00:24:38,705
Two satellites that had simultaneously
circled the planet for a dozen years
220
00:24:38,706 --> 00:24:40,258
had collided.
221
00:24:40,900 --> 00:24:43,897
Cosmos, as it turned
out, was a dead satellite,
222
00:24:43,898 --> 00:24:48,799
ceasing to function in 1995, just
two years after it was launched.
223
00:24:51,800 --> 00:24:58,521
Now more than a 100,000 pieces from
this collision cloud Low-Earth Orbit.
224
00:25:01,900 --> 00:25:05,662
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,
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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,
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sits the remote
hyper-velocity test laboratory,
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where engineers are providing
solutions required to advance
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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,
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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,
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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
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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,
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where they detect and
catalogue man-made objects.
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Utilising a vast array
of RADARs and sensors,
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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
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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
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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
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bring back the pristine environment
that we would like space to be.
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Scientists and engineers are
developing breakthrough innovations to
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help us begin cleaning
up space someday soon.
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The question is: How do we
catch up to and capture
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debris tumbling through Low-Earth
Orbit at thousands of miles an hour?
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And then, how do we slow it down,
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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,
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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
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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
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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
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a brand-new tool for cleaning up space.
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Lasers could one day sweep
space, striking smaller objects,
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slowing them down and causing
them to tumble into the atmosphere.
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Solar sails could someday be
part of the satellites we launch,
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helping them to de-orbit once
their work in space is done.
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Space-faring nations are now working
to develop sustainable methods to
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explore space and new technology to
reclaim what has been left in orbit.
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As we continue to launch our
dreams into space, what if one day
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objects in space were located
and captured by a garbage vehicle?
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The vehicle could then dock
at a recycling facility,
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a place where space debris could be
stored and recycled to create new parts.
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Imagine...
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Aluminium and fuel from
centuries old upper-stage rockets
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recovered and poured into an
industrial outer space post...
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00:32:53,600 --> 00:32:56,865
Industrialising space is never
and issue of science fiction.
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It's more of a question
of do we want to do it and
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when do we have the infrastructure
established so that we can do it.
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It's work we will do in the
future as move out into space.
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Space-based recycling could
someday become a reality,
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launching a new, greener
era of space exploration.
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For as long as humans
have walked the planet,
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we've looked at the heavens to help
us define our role in the universe.
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The celestial bodies in our skies
and the constellations they form
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have forever shaped our
notions of time and place.
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Today, constellations of our
own making fill the night skies
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as we continue to push skyward, relying
on what the universe has taught us.
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Where would we be, if we
couldn't consult the stars?
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Growing up, it was my fantasy
that I would get to see humanity
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spread off of the Earth and
throughout the Solar System.
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So do I think this snowballing
event will actually happen?
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I can't imagine after
dreaming and working toward
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00:34:19,145 --> 00:34:22,179
space flight and after 50
years of having achieved it,
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that we would ever cut
ourselves off from space.
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That does against everything that
humanity has ever strived for.
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My legacy will probably always include
being knows as the father of "space junk."
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What I hope that means is
that we continue to maintain
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access to space and learn more
about life and the environment.31177
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