Why Can't We See Evidence of Alien Life?
-
0:16 - 0:19Somewhere out there in that vast universe,
-
0:19 - 0:23there must surely be countless
other planets teeming with life, -
0:23 - 0:25but why don't we see any evidence of it?
-
0:26 - 0:29Well, this is the famous question
asked by Enrico Fermi in 1950: -
0:29 - 0:30"Where is everybody?"
-
0:32 - 0:35Conspiracy theorists claim
that UFOs are visiting all the time -
0:35 - 0:37and the reports are just being covered up,
-
0:37 - 0:40but honestly, they aren't very convincing.
-
0:41 - 0:42But that leaves a real riddle.
-
0:43 - 0:45In the past year,
the Kepler space observatory -
0:45 - 0:49has found hundreds of planets
just around nearby stars, -
0:49 - 0:51and if you extrapolate that data,
-
0:51 - 0:54it looks like there could be
half a trillion planets -
0:54 - 0:56just in our own galaxy.
-
0:57 - 1:01If any one in 10,000 has conditions
that might support a form of life, -
1:01 - 1:05that's still 50 million possible
life-harboring planets -
1:05 - 1:06right here in the Milky Way.
-
1:07 - 1:08So here's the riddle.
-
1:09 - 1:10Our Earth didn't form
-
1:10 - 1:13until about 9 billion years
after the Big Bang. -
1:14 - 1:18Countless other planets in our galaxy
should have formed earlier -
1:18 - 1:20and given life a chance to get underway
-
1:20 - 1:23billions or certainly
many millions of years -
1:23 - 1:25earlier than happened on Earth.
-
1:26 - 1:28If just a few of them
had spawned intelligent life -
1:28 - 1:31and started creating technologies,
-
1:31 - 1:34those technologies
would have had millions of years -
1:34 - 1:37to grow in complexity and power.
-
1:38 - 1:39On Earth,
-
1:39 - 1:42we've seen how dramatically
technology can accelerate -
1:42 - 1:44in just 100 years.
-
1:45 - 1:49In millions of years,
an intelligent alien civilization -
1:49 - 1:51could easily have spread out
across the galaxy, -
1:51 - 1:55perhaps creating giant
energy-harvesting artifacts, -
1:55 - 1:58or fleets of colonizing spaceships,
-
1:58 - 2:00or glorious works of art
that fill the night sky. -
2:02 - 2:05At the very least, you'd think
they'd be revealing their presence, -
2:05 - 2:06deliberately or otherwise,
-
2:06 - 2:09through electromagnetic signals
of one kind or another. -
2:10 - 2:12And yet we see no convincing
evidence of any of it. -
2:12 - 2:13Why?
-
2:15 - 2:18Well, there are numerous possible answers,
-
2:18 - 2:19some of them quite dark.
-
2:20 - 2:23Maybe a single,
superintelligent civilization -
2:23 - 2:26has indeed taken over the galaxy,
-
2:26 - 2:28and has imposed strict radio silence
-
2:28 - 2:31because it's paranoid
of any potential competitors. -
2:31 - 2:34It's just sitting there
ready to obliterate -
2:34 - 2:36anything that becomes a threat.
-
2:38 - 2:40Or maybe they're not that intelligent.
-
2:41 - 2:43Or perhaps, the evolution
of an intelligence -
2:43 - 2:46capable of creating
sophisticated technology -
2:46 - 2:48is far rarer than we've assumed.
-
2:48 - 2:49After all,
-
2:49 - 2:51it's only happened once on Earth
-
2:51 - 2:52in 4 billion years.
-
2:53 - 2:55Maybe even that was incredibly lucky.
-
2:55 - 2:58Maybe we are the first
such civilization in our galaxy. -
3:00 - 3:03Or, perhaps, civilization carries with it
-
3:03 - 3:04the seeds of its own destruction
-
3:04 - 3:08through the inability to control
the technologies it creates. -
3:10 - 3:12But there are numerous
more hopeful answers. -
3:12 - 3:14For a start, we're not looking that hard,
-
3:14 - 3:17and we're spending a pitiful
amount of money on it. -
3:17 - 3:20Only a tiny fraction
of the stars in our galaxy -
3:20 - 3:24have really been looked at closely
for signs of interesting signals. -
3:25 - 3:27And perhaps, we're not looking
the right way. -
3:27 - 3:30Maybe as civilizations develop,
-
3:30 - 3:32they quickly discover
communication technologies -
3:32 - 3:36far more sophisticated and useful
than electromagnetic waves. -
3:37 - 3:39Maybe all the action takes place
-
3:39 - 3:42inside the mysterious
recently discovered dark matter, -
3:42 - 3:44or dark energy,
-
3:44 - 3:46that appear to account
for most of the universe's mass. -
3:48 - 3:51Or maybe we're looking at the wrong scale.
-
3:51 - 3:53Perhaps intelligent civilizations
come to realize -
3:53 - 3:57that life is ultimately just complex
patterns of information -
3:57 - 3:59interacting with each other
in a beautiful way, -
3:59 - 4:01and that can happen
more efficiently at a small scale. -
4:02 - 4:06So just as on Earth, clunky stereo systems
have shrunk to beautiful, tiny iPods, -
4:06 - 4:08maybe intelligent life itself,
-
4:08 - 4:10in order to reduce its footprint
on the environment, -
4:11 - 4:12has turned itself microscopic,
-
4:12 - 4:14so the Solar System
might be teeming with aliens, -
4:14 - 4:16and we're just not noticing them.
-
4:16 - 4:19Maybe the very ideas in our heads
are a form of alien life. -
4:20 - 4:22Well, okay, that's a crazy thought.
-
4:22 - 4:24The aliens made me say it.
-
4:25 - 4:29But it is cool that ideas do seem
to have a life all of their own, -
4:29 - 4:31and that they outlive their creators.
-
4:32 - 4:36Maybe biological life
is just a passing phase. -
4:37 - 4:40Well, within the next 15 years,
-
4:40 - 4:43we could start seeing
real spectroscopic information -
4:43 - 4:44from promising nearby planets
-
4:44 - 4:47that will reveal just how
life-friendly they might be. -
4:47 - 4:48And meanwhile SETI,
-
4:48 - 4:51the Search for
Extra-Terrestrial Intelligence, -
4:51 - 4:53is now releasing its data to the public
-
4:53 - 4:56so that millions of citizen scientists,
maybe including you, -
4:56 - 4:58can bring the power of the crowd
to join the search. -
4:59 - 5:02And here on Earth,
amazing experiments are being done -
5:02 - 5:04to try to create life from scratch,
-
5:04 - 5:07life that might be very different
from the DNA forms we know. -
5:08 - 5:10All of this will help us understand
-
5:10 - 5:12whether the universe is teeming with life
-
5:13 - 5:14or, whether indeed,
-
5:15 - 5:16it's just us.
-
5:18 - 5:21Either answer, in its own way,
-
5:21 - 5:23is awe-inspiring,
-
5:24 - 5:26because even if we are alone,
-
5:26 - 5:28the fact that we think and dream,
-
5:28 - 5:30and ask these questions
-
5:30 - 5:33might yet turn out to be
one of the most important facts -
5:33 - 5:34about the universe.
-
5:35 - 5:38And I have one more piece
of good news for you. -
5:38 - 5:40The quest for knowledge
and understanding never gets dull. -
5:40 - 5:42It doesn't. It's actually the opposite.
-
5:42 - 5:44The more you know,
-
5:44 - 5:46the more amazing the world seems.
-
5:46 - 5:50And it's the crazy possibilities,
the unanswered questions, -
5:50 - 5:51that pull us forward.
-
5:51 - 5:54So, stay curious.
- Title:
- Why Can't We See Evidence of Alien Life?
- Speaker:
- Chris Anderson
- Description:
-
Stand by for an animated exploration of the famous Fermi Paradox. Given the vast number of planets in the universe, many much older than Earth, why haven't we yet seen obvious signs of alien life? The potential answers to this question are numerous and intriguing, alarming and hopeful.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TED-Ed
- Duration:
- 06:04
Krystian Aparta commented on English subtitles for Why can't we see evidence of alien life? | ||
Krystian Aparta edited English subtitles for Why can't we see evidence of alien life? | ||
Sara Bgd edited English subtitles for Why can't we see evidence of alien life? | ||
Jenny Zurawell edited English subtitles for Why can't we see evidence of alien life? | ||
Francesca Pratali edited English subtitles for Why can't we see evidence of alien life? | ||
Francesca Pratali edited English subtitles for Why can't we see evidence of alien life? | ||
Jenny Zurawell approved English subtitles for Why can't we see evidence of alien life? | ||
Jenny Zurawell edited English subtitles for Why can't we see evidence of alien life? |
Krystian Aparta
The English transcript was updated on 10/4/2016.