How humanity can reach the stars
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0:01 - 0:04We're here at the University
of California, Santa Barbara -
0:04 - 0:06to discuss a dream of humanity:
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0:06 - 0:09the ability to exit our solar system
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0:09 - 0:12and enter another solar system.
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0:12 - 0:15And the solution is literally
before your eyes. -
0:16 - 0:18So I have two things on me
that you have -- I have a watch, -
0:18 - 0:20and I have a flashlight,
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0:20 - 0:22which, if it's not on you,
it's on your phone. -
0:22 - 0:24So the watch keeps time,
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0:24 - 0:27and my flashlight
just illuminates my environment. -
0:27 - 0:30So like art, to me,
science is illuminating. -
0:30 - 0:33I want to see reality in a different way.
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0:33 - 0:34When I turn on the flashlight,
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0:34 - 0:37suddenly the dark becomes bright,
and I suddenly see. -
0:37 - 0:39The flashlight and its light,
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0:39 - 0:40which you can see coming out --
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0:40 - 0:43the light on my hand
is not only illuminating my hand, -
0:43 - 0:45it's actually pushing on my hand.
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0:45 - 0:47Light carries energy and momentum.
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0:47 - 0:50So the answer is not to make a spacecraft
out of a flashlight, -
0:50 - 0:52by having the exhaust come out this way
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0:52 - 0:54and the spacecraft goes that way --
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0:54 - 0:56that's what we do today with chemistry.
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0:56 - 0:57The answer is this:
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0:57 - 1:00Take the flashlight and put it
somewhere on the Earth, -
1:00 - 1:01in orbit or on the Moon,
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1:01 - 1:03and then shine it on a reflector,
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1:03 - 1:07which propels the reflector to speeds
which can approach the speed of light. -
1:07 - 1:09Well, how do you make a flashlight
that's big enough? -
1:09 - 1:11This isn't going to do it,
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1:11 - 1:13my hand doesn't seem to be going anywhere.
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1:13 - 1:15And that's because the force
is very, very low. -
1:15 - 1:17So the way that you can solve this problem
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1:17 - 1:20is taking many, many flashlights,
which are actually lasers, -
1:20 - 1:21and synchronizing them in time,
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1:21 - 1:25and when you gang them all together
into a gigantic array, -
1:25 - 1:27which we call a phased array,
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1:27 - 1:30you then have a sufficiently
powerful system, -
1:30 - 1:33which, if you make it roughly
the size of a city, -
1:33 - 1:37it can push a spacecraft,
which is roughly the size of your hand, -
1:37 - 1:41to speeds which are roughly
25 percent the speed of light. -
1:41 - 1:45That would enable us to get
to the nearest star, Proxima Centauri, -
1:45 - 1:47which is a little over
four light years away, -
1:47 - 1:49in less than 20 years.
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1:50 - 1:53Initial probes would be
roughly the size of your hand, -
1:53 - 1:56and the size of the reflector
that you're going to use -
1:56 - 1:57is going to be roughly human size,
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1:58 - 2:00so not a whole lot larger than myself,
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2:00 - 2:01but a few meters in size.
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2:01 - 2:08It only uses the reflection of light
from this very large laser array -
2:08 - 2:09to propel the spacecraft.
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2:09 - 2:11So let's talk about this.
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2:11 - 2:15This is a lot like sailing on the ocean.
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2:15 - 2:18When you sail on the ocean,
you're pushed by the wind. -
2:18 - 2:21And the wind then drives the sail
forward through the water. -
2:21 - 2:24In our case, we're creating
an artificial wind in space -
2:24 - 2:26from this laser array,
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2:26 - 2:29except the wind is actually the photons
from the laser itself, -
2:29 - 2:32the light from the laser becomes the wind
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2:32 - 2:34upon which we sail.
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2:34 - 2:35It is a very directed light --
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2:35 - 2:37it's often called directed energy.
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2:37 - 2:39So why is this possible today,
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2:39 - 2:41why can we talk about
going to the stars today, -
2:41 - 2:43when 60 years ago,
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2:43 - 2:46when the space program began in earnest,
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2:46 - 2:48people would have said,
"That's not possible"? -
2:48 - 2:52Well, the reason it's possible today
has a lot to do with the consumer, -
2:52 - 2:54and the very fact that you're watching me.
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2:55 - 2:57You're watching me
over a high-speed internet, -
2:57 - 3:02which is dominated by the photonics
of sending data over fiber optics. -
3:03 - 3:07Photonics essentially allow
the internet to exist -
3:07 - 3:08in the way it does today.
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3:08 - 3:11The ability to send vast amounts
of data very quickly -
3:11 - 3:14is the same technology
that we're going to use -
3:14 - 3:17to send spacecraft
very quickly to the stars. -
3:17 - 3:20You effectively have an infinite
supply of propellent, -
3:20 - 3:21you can turn it on and off as needed.
-
3:21 - 3:27You do not leave the laser array
that produces the light on -
3:27 - 3:28for the entire journey.
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3:28 - 3:31For small spacecraft,
it's only on for a few minutes, -
3:31 - 3:34and then it's like shooting a gun.
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3:34 - 3:38You have a projectile
which just moves ballistically. -
3:38 - 3:42Even if we, as humans,
are not on the spacecraft, -
3:42 - 3:45at least we have the ability
to send out such spacecraft. -
3:45 - 3:47You want to remotely view,
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3:47 - 3:51or have remote imaging and remote sensing,
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3:51 - 3:52of an object.
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3:52 - 3:55So when we go to Jupiter, for example,
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3:55 - 3:57with a flyby mission,
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3:57 - 3:59we are taking pictures of Jupiter,
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3:59 - 4:00we're measuring the magnetic field,
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4:00 - 4:02the particle density,
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4:02 - 4:04and we're basically exploring remotely.
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4:04 - 4:05The same way that you are looking at me.
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4:06 - 4:09And all of the current missions
that are beyond the Moon -
4:09 - 4:11are remote-sensing missions.
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4:11 - 4:14What would we hope to find
if we visited an exoplanet? -
4:14 - 4:16Perhaps there's life on an exoplanet,
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4:16 - 4:19and we would be able to see
evidence of life, -
4:19 - 4:21either through atmospheric biosignatures
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4:21 - 4:23or through, you know, a dramatic picture,
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4:23 - 4:26we would be able to see something
actually on the surface. -
4:26 - 4:29We don't know if there's life
elsewhere in the universe. -
4:29 - 4:32Perhaps on the missions that we send out,
we will find evidence for life, -
4:32 - 4:34perhaps we will not.
-
4:34 - 4:37And while economics may seem
like an inappropriate thing -
4:37 - 4:41to bring into a talk
on interstellar capability, -
4:41 - 4:46it is in fact one of the driving issues
in achieving interstellar capability. -
4:46 - 4:51You have to get things to the point
where they're economically affordable -
4:51 - 4:52to do what we want to do.
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4:52 - 4:53So currently,
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4:53 - 4:55we have systems in the lab
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4:55 - 5:00which have achieved the ability
to synchronize over very large scales, -
5:00 - 5:04out to about 10 kilometers
or roughly six miles. -
5:04 - 5:07We've been able to achieve
synchronization of laser systems, -
5:07 - 5:09and it's worked beautifully.
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5:09 - 5:13We've known how to build lasers
for many decades, -
5:13 - 5:17but it's only now that the technology
has gotten inexpensive enough, -
5:17 - 5:19and become mature enough
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5:19 - 5:24that we can imagine
having huge arrays, literally, -
5:24 - 5:27kilometer-scale arrays,
much like solar farms, -
5:27 - 5:32but instead of receiving light,
they transmit light. -
5:32 - 5:38The beauty of this type of technology
is it enables many applications, -
5:38 - 5:40not just relativistic flight
for small spacecraft, -
5:41 - 5:43but enables high-speed spacecraft,
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5:43 - 5:46high-speed flight in our solar system,
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5:46 - 5:47it enables planetary defense,
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5:47 - 5:50it enables space debris removal,
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5:50 - 5:56it enables powering of distant assets
that we may want to send power to, -
5:56 - 5:59such as spacecraft or bases
on the Moon or other places. -
5:59 - 6:02It's an extremely versatile technology,
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6:02 - 6:04it's something that humanity
would want to develop -
6:04 - 6:07even if they didn't want
to send spacecraft to the stars, -
6:07 - 6:10because that technology
allows so many applications -
6:10 - 6:13that are currently not feasible.
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6:13 - 6:15And therefore, I feel
it's an inevitable technology, -
6:15 - 6:17because we have the ability,
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6:17 - 6:20we just need to fine-tune the technology
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6:20 - 6:23and in a sense, wait for economics
to catch up with us -
6:23 - 6:27so that it becomes cheap enough
to build the large systems. -
6:27 - 6:29The smaller systems are affordable now.
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6:29 - 6:33And we've already started building
prototype systems in our lab. -
6:33 - 6:35So while it's not
going to happen tomorrow, -
6:35 - 6:37we've already begun the process,
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6:37 - 6:39and so far, it's looking good.
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6:39 - 6:43This is both a revolutionary program,
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6:43 - 6:46in terms of being
a transformative technology, -
6:46 - 6:49but it's also an evolutionary program.
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6:49 - 6:53So personally,
I do not expect to be around -
6:53 - 6:57when the first
relativistic flight happens. -
6:57 - 7:00I think that's probably 30-plus years off
before we get to that point, -
7:00 - 7:02and perhaps more.
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7:02 - 7:03But what inspires me
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7:03 - 7:06is to look at the ability
to achieve the final goal. -
7:06 - 7:09Even if it does not happen in my lifetime,
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7:09 - 7:12it can happen in the lifetime
of the next generation -
7:12 - 7:13or the generation beyond that.
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7:13 - 7:16The consequences are so transformative
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7:16 - 7:20that we literally, in my opinion,
must go down this path, -
7:20 - 7:22and must explore what the limitations are,
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7:22 - 7:24and then how do we overcome
the limitations. -
7:24 - 7:26The search for life on other planets
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7:26 - 7:30would be one of humanity's
foremost explorations, -
7:30 - 7:32and if we're able to do so,
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7:32 - 7:35and actually find life on another planet,
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7:35 - 7:37it would change humanity forever.
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7:37 - 7:38Everything is profound in life.
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7:38 - 7:40If you look deep enough,
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7:40 - 7:44you'll find something incredibly complex
and interesting and beautiful in life. -
7:45 - 7:48And the same is true
with the lowly photon -
7:48 - 7:51that we use to see every day.
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7:51 - 7:56But when we look outside
and we imagine something vastly greater, -
7:56 - 7:59an array of lasers that are synchronized,
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7:59 - 8:03we could imagine things
which are just extraordinary in life. -
8:03 - 8:05And the ability to go to another star
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8:05 - 8:08is one of those
extraordinary capabilities. -
8:09 - 8:14(Birds chirping)
- Title:
- How humanity can reach the stars
- Speaker:
- Philip Lubin
- Description:
-
Could we exit our solar system, and enter another? Astrophysicist Philip Lubin discusses the awesome potential of using lasers to propel small spacecraft, enabling humanity's first interstellar missions. Learn how this transformative technology could help us reach Proxima Centauri, the nearest star to our own -- and fundamentally alter our understanding of the universe along the way.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 08:31
marialadias edited English subtitles for How humanity can reach the stars | ||
Erin Gregory approved English subtitles for How humanity can reach the stars | ||
Erin Gregory edited English subtitles for How humanity can reach the stars | ||
Krystian Aparta accepted English subtitles for How humanity can reach the stars | ||
Krystian Aparta edited English subtitles for How humanity can reach the stars | ||
Ivana Korom edited English subtitles for How humanity can reach the stars | ||
Ivana Korom edited English subtitles for How humanity can reach the stars |