0:00:00.817,0:00:02.433
Our lives depend

0:00:02.433,0:00:05.151
on a world we can't see.

0:00:05.151,0:00:07.181
Think about your week so far.

0:00:07.181,0:00:10.457
Have you watched TV, used GPS,

0:00:10.457,0:00:11.861
checked the weather, or even at a meal?

0:00:11.861,0:00:16.663
These many things that enable[br]our daily lives

0:00:16.663,0:00:19.382
rely either directly or indirectly

0:00:19.382,0:00:21.074
on satellites,

0:00:21.074,0:00:23.145
and while we often take for granted

0:00:23.145,0:00:25.614
the services that satellites provide us,

0:00:25.614,0:00:28.531
the satellites themselves[br]deserve our attention

0:00:28.531,0:00:30.532
as they are leaving a lasting mark

0:00:30.532,0:00:32.838
on the space they occupy.

0:00:32.838,0:00:36.645
People around the world[br]rely on satellite infrastructure every day

0:00:36.645,0:00:39.161
for information, entertainment,[br]and to communicate.

0:00:39.161,0:00:43.156
There's agricultural[br]and environmental monitoring,

0:00:43.156,0:00:46.610
Internet connectivity, navigation.

0:00:46.610,0:00:50.478
Satellites even play a role[br]in the operation of our financial

0:00:50.478,0:00:52.362
and energy markets.

0:00:52.362,0:00:54.272
But these satellites that we rely on

0:00:54.272,0:00:56.350
day in and day out

0:00:56.350,0:00:57.610
have a finite life.

0:00:57.610,0:00:59.594
They might run out of propellant,

0:00:59.594,0:01:00.929
they could malfunction,

0:01:00.929,0:01:04.826
or they may just naturally reach[br]the end of their mission life.

0:01:04.826,0:01:09.637
At this point, these satellites[br]effectively become space junk,

0:01:09.637,0:01:11.941
cluttering the orbital environment.

0:01:11.941,0:01:15.704
So imagine you're driving down the highway[br]on a beautiful, sunny day

0:01:15.704,0:01:17.197
out running errands.

0:01:17.197,0:01:18.778
You've got your music cranked,

0:01:18.778,0:01:20.370
your windows rolled down,

0:01:20.370,0:01:23.023
with the cool breeze[br]blowing through your hair.

0:01:23.023,0:01:24.469
Feels nice, right?

0:01:24.469,0:01:26.838
Everything is going smoothly

0:01:26.838,0:01:29.959
until suddenly your car[br]stutters and stalls

0:01:29.959,0:01:32.246
right in the middle of the highway.

0:01:32.246,0:01:35.727
So now you have no choice[br]but to abandon your car

0:01:35.727,0:01:37.687
where it is on the highway.

0:01:37.687,0:01:40.797
Maybe you were lucky enough to be able[br]to move it out of the way

0:01:40.797,0:01:44.888
and into a shoulder lane so that it's[br]out of the way of other traffic.

0:01:44.888,0:01:48.280
A couple of hours ago, your car[br]was a useful machine

0:01:48.280,0:01:51.138
that you relied on in your everyday life.

0:01:51.138,0:01:53.804
Now, it's a useless hunk of metal

0:01:53.804,0:01:58.000
taking up space in a valuable[br]transportation network.

0:01:58.000,0:02:02.408
And imagine international roadways[br]all cluttered with broken down vehicles

0:02:02.408,0:02:05.151
that are just getting in the way[br]of other traffic,

0:02:05.151,0:02:08.011
and imagine the debris that would[br]be strewn everywhere

0:02:08.011,0:02:10.575
if a collision actually happened,

0:02:10.575,0:02:12.975
thousands of smaller pieces of debris

0:02:12.975,0:02:15.868
becoming new obstacles.

0:02:15.868,0:02:19.305
This is the paradigm[br]of the satellite industry.

0:02:19.305,0:02:22.134
Satellites that are no longer working

0:02:22.134,0:02:25.472
are often left to de-orbit[br]over many, many years,

0:02:25.472,0:02:28.926
or only moved out of the way[br]as a temporary solution,

0:02:28.926,0:02:31.321
and there are no international[br]laws in space

0:02:31.321,0:02:34.483
to enforce us to clean up after ourselves.

0:02:34.483,0:02:36.983
So the world's first satellite, Sputnik I,

0:02:36.983,0:02:39.316
was launched in 1957,

0:02:39.316,0:02:43.559
and in that year, there were only[br]a total of three launch attempts.

0:02:43.559,0:02:47.372
Decades later and dozens of countries[br]from all around the world

0:02:47.372,0:02:50.318
have launched thousands[br]of more satellites into orbit,

0:02:50.318,0:02:54.546
and the frequency of launches[br]is only going to increase in the future,

0:02:54.546,0:02:57.086
especially if you consider things[br]like the possibility

0:02:57.086,0:03:01.333
of 900-plus satellite constellations[br]being launched.

0:03:01.333,0:03:03.861
Now, we send satellites[br]to different orbits

0:03:03.861,0:03:05.968
depending on what they're needed for.

0:03:05.968,0:03:08.338
One of the most common places[br]we send satellites

0:03:08.338,0:03:09.935
is the low Earth orbit,

0:03:09.935,0:03:11.906
possibly to image the surface of Earth

0:03:11.906,0:03:14.802
at up to about 2,000 kilometers altitude.

0:03:14.802,0:03:18.267
Satellites there are naturally buffeted[br]by Earth's atmosphere,

0:03:18.267,0:03:20.198
so their orbits naturally decay,

0:03:20.198,0:03:21.792
and they'll eventually burn up,

0:03:21.792,0:03:24.450
probably within a couple of decades.

0:03:24.450,0:03:26.608
Another common place we send satellites

0:03:26.608,0:03:28.448
is the geostationary orbit

0:03:28.448,0:03:31.372
at about 35,000 kilometers altitude.

0:03:31.372,0:03:35.820
Satellites there remain in the same place[br]above Earth as the Earth rotates,

0:03:35.820,0:03:40.450
which enables things like communications[br]or television broadcast, for example.

0:03:40.450,0:03:45.364
Satellites in high orbits like these[br]could remain there for centuries.

0:03:45.364,0:03:49.463
And then there's the orbit coined[br]"the graveyard,"

0:03:49.463,0:03:51.974
the ominous junk or disposal orbits,

0:03:51.974,0:03:54.555
where some satellites[br]are intentionally placed

0:03:54.555,0:03:57.662
at the end of their life[br]so that they're out of the way

0:03:57.662,0:04:00.509
of common operational orbits.

0:04:00.509,0:04:05.679
Of the nearly 7,000 satellites launched[br]since the late 1950s,

0:04:05.679,0:04:09.487
only about one in seven[br]is currently operational,

0:04:09.487,0:04:12.331
and in addition to the satellites[br]that are no longer working,

0:04:12.331,0:04:15.864
there's also hundreds of thousands[br]of marble-sized debris,

0:04:15.864,0:04:18.382
and millions of paint chip-sized debris

0:04:18.382,0:04:21.095
that are also orbiting around the Earth.

0:04:21.095,0:04:23.840
Space debris is a major risk[br]to space missions,

0:04:23.840,0:04:28.465
but also to the satellites that we rely on[br]each and every day.

0:04:28.465,0:04:32.145
Now, because space debris and junk[br]has become increasingly worrisome,

0:04:32.145,0:04:34.725
there have been some national[br]and international efforts

0:04:34.725,0:04:38.515
to develop technical standards[br]to help us limit the generation

0:04:38.515,0:04:39.737
of additional debris.

0:04:39.737,0:04:41.973
So for example, there are recommendations

0:04:41.973,0:04:43.939
for those low Earth orbiting spacecraft

0:04:43.939,0:04:47.341
to be made to de-orbit in under 25 years,

0:04:47.341,0:04:49.624
but that's still a really long time,

0:04:49.624,0:04:53.702
especially if a satellite[br]hasn't been working for years.

0:04:53.702,0:04:56.592
There's also mandates for those[br]dead geostationary spacecraft

0:04:56.592,0:04:59.144
to be moved into a graveyard orbit.

0:04:59.144,0:05:03.521
But neither of these guidelines[br]is binding under international law,

0:05:03.521,0:05:08.387
and the understanding is that they will be[br]implemented through national mechanisms.

0:05:08.387,0:05:10.661
These guidelines are also not long-term,

0:05:10.661,0:05:12.251
they're not proactive,

0:05:12.251,0:05:15.421
nor do they address the debris[br]that's already up there.

0:05:15.421,0:05:19.946
They're only in place to limit[br]the future creation of debris.

0:05:19.946,0:05:22.986
Space junk is no one's responsibility.

0:05:23.740,0:05:26.668
Now, Mt. Everest is actually[br]an interesting comparison

0:05:26.668,0:05:29.579
of a new approach to how we[br]interact with our environments,

0:05:29.579,0:05:32.260
as it's often given the dubious honor

0:05:32.260,0:05:35.916
of being the world's highest garbage dump.

0:05:35.916,0:05:39.510
Decades after the first conquest[br]of the world's highest peak,

0:05:39.510,0:05:41.773
tons of rubbish left behind by climbers

0:05:41.773,0:05:45.127
has started to raise concern,

0:05:45.127,0:05:46.482
and you may have read in the news[br]that there's speculation

0:05:46.482,0:05:48.406
that Nepal will crack down on mountaineers

0:05:48.406,0:05:52.714
with stricter enforcement of penalties[br]and legal obligations.

0:05:52.714,0:05:55.246
The goal, of course,[br]is to persuade climbers

0:05:55.246,0:05:57.514
to clean up after themselves,

0:05:57.514,0:06:02.332
so maybe local non-for-profits will pay[br]climbers who bring down extra waste,

0:06:02.332,0:06:06.350
or expeditions might organize[br]voluntary cleanup trips.

0:06:06.350,0:06:08.613
And yet still many climbers feel

0:06:08.613,0:06:12.264
that independent groups[br]should police themselves.

0:06:12.264,0:06:15.322
There's no simple or easy answer,

0:06:15.322,0:06:18.218
and even well-intentioned efforts[br]at conservation

0:06:18.218,0:06:20.368
often run into problems.

0:06:20.368,0:06:23.642
But that doesn't mean we shouldn't[br]do everything in our power

0:06:23.642,0:06:27.506
to protect the environments[br]that we rely and depend on,

0:06:27.506,0:06:31.697
and like Everest, the remote location[br]and inadequate infrastructure

0:06:31.697,0:06:33.120
of the orbital environment

0:06:33.120,0:06:35.810
make waste disposal a challenging problem.

0:06:35.810,0:06:38.556
But we simply cannot reach new heights

0:06:38.556,0:06:41.680
and create an even higher garbage dump,

0:06:41.680,0:06:44.747
one that's out of this world.

0:06:44.747,0:06:49.244
The reality of space is that if[br]a component on a satellite breaks down,

0:06:49.244,0:06:51.327
there really are limited opportunities

0:06:51.327,0:06:54.817
for repairs and only at great cost.

0:06:54.817,0:06:58.535
But what if we were smarter[br]about how we designed satellites?

0:06:58.535,0:06:59.849
What if all satellites,

0:06:59.849,0:07:01.986
regardless of what country[br]they were built in,

0:07:01.986,0:07:04.156
had to be standardized in some way

0:07:04.156,0:07:06.344
for recycling, servicing,

0:07:06.344,0:07:08.746
or active de-orbiting?

0:07:08.746,0:07:12.170
What if there actually were[br]international laws with teeth

0:07:12.170,0:07:15.064
that enforced end-of-life[br]disposal of satellites

0:07:15.064,0:07:17.291
instead of moving them out of the way

0:07:17.291,0:07:19.701
as a temporary solution?

0:07:19.701,0:07:23.849
Or maybe satellites manufacturers[br]need to be charged to deposit

0:07:23.849,0:07:25.429
to even launch a satellite into orbit,

0:07:25.429,0:07:27.511
and that deposit would only be returned

0:07:27.511,0:07:29.654
if the satellite was disposed of properly

0:07:29.654,0:07:33.811
or if they cleaned up[br]some quota of debris.

0:07:33.811,0:07:36.310
Or maybe a satellite needs to have[br]technology on board

0:07:36.310,0:07:38.645
to help accelerate de-orbit.

0:07:38.645,0:07:41.250
There are some encouraging signs.

0:07:41.250,0:07:44.845
The UK's TechDemoSat-1,[br]launched in 2014, for example,

0:07:44.845,0:07:48.016
was designed for end-of-life disposal

0:07:48.016,0:07:49.941
via a small drag sale.

0:07:49.941,0:07:52.391
This works for the satellite[br]because it's small,

0:07:52.391,0:07:56.126
but satellites that are higher[br]or in larger orbits

0:07:56.126,0:07:57.586
or are larger altogether,[br]like the size of school buses,

0:07:57.586,0:08:01.481
will require other disposal options.

0:08:01.481,0:08:04.446
So maybe you get into things like[br]high-powered lasers

0:08:04.446,0:08:06.466
or tugging using nets or tethers,

0:08:06.466,0:08:09.005
as crazy as those sound in the short term.

0:08:09.005,0:08:11.214
And then one really cool possibility

0:08:11.214,0:08:14.793
is the idea of orbital tow trucks[br]or space mechanics.

0:08:14.793,0:08:17.270
Imagine if a robotic arm

0:08:17.270,0:08:18.905
on some sort of space tow truck

0:08:18.905,0:08:21.178
could fix the broken components[br]on a satellite,

0:08:21.178,0:08:23.311
making them usable again.

0:08:23.311,0:08:26.602
Or what if that very same robotic arm

0:08:26.602,0:08:27.941
could refuel the propellant tank[br]on a spacecraft

0:08:27.941,0:08:29.694
that relies on chemical propulsion

0:08:29.694,0:08:33.773
just like you or I would refuel[br]the fuel tanks on our cars?

0:08:33.773,0:08:35.457
Robotic repair and maintenance

0:08:35.457,0:08:40.448
could extend the lives of hundreds[br]of satellites orbiting around the Earth.

0:08:40.448,0:08:43.342
Whatever the disposal[br]or cleanup options we come up with,

0:08:43.342,0:08:46.204
it's clearly not just a technical problem.

0:08:46.204,0:08:51.497
There's also complex space laws[br]and politics that we have to sort out.

0:08:51.497,0:08:56.234
Simply put, we haven't found a way[br]to use space sustainably yet.

0:08:56.234,0:08:59.809
Exploring, innovating to change[br]the way we live and work,

0:08:59.809,0:09:01.713
are what we as humans do,

0:09:01.713,0:09:03.203
and in space exploration,

0:09:03.203,0:09:06.458
we're literally moving beyond[br]the boundaries of Earth.

0:09:06.458,0:09:10.242
But as we push thresholds[br]in the name of learning and innovation,

0:09:10.242,0:09:16.332
we must remember that accountability[br]for our environments never goes away.

0:09:16.332,0:09:21.013
There is without doubt congestion[br]in the low-Earth and geostationary orbits,

0:09:21.013,0:09:23.252
and we cannot keep[br]launching new satellites

0:09:23.252,0:09:25.335
to replace the ones that have broken down

0:09:25.335,0:09:27.704
without doing something about them first,

0:09:27.704,0:09:29.956
just like we would never leave[br]a broken down car

0:09:29.956,0:09:31.916
in the middle of the highway.

0:09:31.916,0:09:33.443
Next time you use your phone,

0:09:33.443,0:09:36.048
check the weather, or use your GPS,

0:09:36.048,0:09:40.169
think about the satellite technologies[br]that make those activities possible,

0:09:40.169,0:09:43.641
but also think about the very impact[br]that the satellites have

0:09:43.641,0:09:45.665
on the environment surrounding Earth,

0:09:45.665,0:09:46.982
and help spread the message

0:09:46.982,0:09:48.784
that together, we must reduce our impact.

0:09:48.784,0:09:52.680
Earth orbit is breathtakingly beautiful

0:09:52.680,0:09:55.410
and our gateway to exploration.

0:09:55.410,0:09:58.294
It's up to us to keep it that way.

0:09:58.294,0:10:00.459
Thank you.

0:10:00.459,0:10:02.538
(Applause)