En el vasto universo que habitamos, la búsqueda de exoplanetas se ha convertido en una de las investigaciones más emocionantes y prometedoras de la astronomía moderna. Los exoplanetas son mundos que orbitan estrellas fuera de nuestro sistema solar, y su estudio no solo nos ayuda a comprender mejor nuestra propia existencia, sino que también abre la posibilidad de encontrar un nuevo hogar para la humanidad. Este documental se sumerge en el fascinante proceso de búsqueda y análisis de estos lejanos cuerpos celestes.
A través de imágenes impactantes y entrevistas con expertos en astrobiología y astronomía, exploraremos los métodos utilizados para detectar exoplanetas, desde el tránsito hasta la velocidad radial. Además, discutiremos las características que hacen que un exoplaneta sea potencialmente habitable, como su ubicación en la zona habitable de su estrella y la presencia de agua líquida. A medida que avanzamos en esta aventura cósmica, descubriremos los descubrimientos más emocionantes hasta la fecha y las misiones futuras que prometen llevarnos más cerca de encontrar un nuevo hogar.
Este documental no solo es un viaje a través del espacio, sino también una reflexión sobre nuestro lugar en el universo y las posibilidades que nos ofrecen los exoplanetas. Únete a nosotros en esta travesía que combina ciencia, exploración y la esperanza de un futuro más allá de la Tierra.
#Exoplanetas, #BúsquedaDeVida, #DocumentalCientífico
**Keywords:** exoplanetas, universo, nuevo hogar, búsqueda de exoplanetas, potencialmente habitable, zona habitable, agua líquida, astronomía, astrobiología, descubrimientos espaciales.
A través de imágenes impactantes y entrevistas con expertos en astrobiología y astronomía, exploraremos los métodos utilizados para detectar exoplanetas, desde el tránsito hasta la velocidad radial. Además, discutiremos las características que hacen que un exoplaneta sea potencialmente habitable, como su ubicación en la zona habitable de su estrella y la presencia de agua líquida. A medida que avanzamos en esta aventura cósmica, descubriremos los descubrimientos más emocionantes hasta la fecha y las misiones futuras que prometen llevarnos más cerca de encontrar un nuevo hogar.
Este documental no solo es un viaje a través del espacio, sino también una reflexión sobre nuestro lugar en el universo y las posibilidades que nos ofrecen los exoplanetas. Únete a nosotros en esta travesía que combina ciencia, exploración y la esperanza de un futuro más allá de la Tierra.
#Exoplanetas, #BúsquedaDeVida, #DocumentalCientífico
**Keywords:** exoplanetas, universo, nuevo hogar, búsqueda de exoplanetas, potencialmente habitable, zona habitable, agua líquida, astronomía, astrobiología, descubrimientos espaciales.
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00:00In this precise moment, on a planet far, far away,
00:29in a galaxy far, far away,
00:35in a galaxy far, far away,
00:41in a galaxy far, far away,
00:48the dawn gives rise to a new day.
00:52In a galaxy far, far away,
00:59in a galaxy far, far away,
01:05But will there be extraterrestrial eyes that can enjoy it?
01:09In a galaxy far, far away,
01:16in a galaxy far, far away,
01:22Or will it go unnoticed?
01:29Maybe it's like any other lost moment in an immense and sterile universe.
01:42We keep looking for the answer.
01:54Magnificent desolation.
01:56A wonderful view.
01:58System ready.
02:12The Milky Way.
02:26Hundreds of thousands of millions of stars.
02:29Distributed in a space of thousands of light years.
02:40Among them, the Sun.
02:49With eight planets orbiting around it.
02:56Among them, our home.
03:00Until recently, they were the only known worlds,
03:05the only planets we could explore to find signs of life outside the Earth.
03:11When I first started in astronomy, in the 1970s,
03:25we didn't know any planets beyond our solar system.
03:28We didn't have the technology to detect them, even if they did exist.
03:32Our neighborhood was the only place we could look for life.
03:38So we began our search in our closest neighborhood.
03:50In recent decades, we have launched several missions to explore the planets of our solar system.
04:02Also to some of its moons.
04:07But until now, although we continue to search,
04:10we have not found any signs of life in any of those worlds.
04:25The Earth remains something unique.
04:29The Earth remains something unique.
04:37The only planet with life in the solar system.
04:50As we continue to explore the solar system,
04:54the search for worlds beyond our domain has begun.
05:03The wonderful thing about astronomy is that as we develop better technologies
05:08and accumulate more and more knowledge about our universe,
05:12we turn more and more into worlds.
05:18For example, we've known for a long time that Mars is a planet.
05:24But tonight, beyond Mars, we see a constellation called Pegasus.
05:31This is the square of Pegasus.
05:34And we know that around there is a star called 51 Pegasi,
05:39which has a planet orbiting around it,
05:43a gas giant the size of Jupiter,
05:46which revolves every four days around that faint point of light.
05:51It is wonderful to think that throughout my adult life,
05:56in the last 25 years,
05:58we've gone from a universe in which there were no planets outside our solar system
06:04to a universe that we know is full of places where we can search for life.
06:21In the last three decades,
06:23some of the Earth's most powerful telescopes have joined the search.
06:34To the hunt for unimaginably distant planets.
06:41Hidden in the dark.
06:45Planets like 51 Pegasi b.
06:55The first world outside our solar system,
06:58detected in orbit around a star similar to the Sun.
07:1451 Pegasi b. is a gaseous giant.
07:18It is half the mass of Jupiter.
07:23But it is closer to its star.
07:30Let's imagine what that planet would be like.
07:34A world in which titanic winds scratch the sky.
07:46And inside it, a rain of sapphires is cooking.
07:5751 Pegasi b. is a giant.
08:0251 Pegasi b. is a very strange world in every way.
08:10And we will soon discover that the galaxy is full of planets
08:14that are nothing like what we have seen in our solar system.
08:26Planets enveloped by intense radiation.
08:32Planets with maltreated surfaces
08:35and swept away by the stroboscopic light of high energy
08:38that irradiates their star.
08:46Or worlds so cold that their atmosphere has frozen.
09:0251 Pegasi b. is a giant.
09:14Or large, swollen planets.
09:21With the density of polystyrene foam.
09:26And unfathomable atmospheres.
09:35These discoveries prove that, in a way, we are not alone.
09:42There are other worlds waiting to be explored.
09:56We calculate that in the Milky Way there are more planets than stars.
10:02Hundreds of thousands of millions.
10:07That means hundreds of thousands of millions of places to seek life.
10:14But there is a complication.
10:16Not all those worlds are like this one.
10:19Not much less.
10:26The first planets we found seemed too strange, too large.
10:30And often they were too close to their stars
10:33for the survival of living beings.
10:45If we wanted to find worlds in which we could explore,
10:49we would have to go to the Milky Way.
10:52If we wanted to find worlds in which life could exist,
10:56we would have to look for smaller rocky planets
10:59and in orbits farther from their stars.
11:07We needed to look for another Earth.
11:10Four. Three. Two.
11:13Ignition. One. Zero.
11:16And takeoff of the Delta II rocket with the Kepler telescope
11:20in search of planets similar to ours.
11:25The tracking was transferred to space
11:27when NASA launched the Kepler space telescope.
11:33Separation completed.
11:36In search of planets similar to Earth
11:39in the vastness of the galaxy.
11:51Kepler traveled 150 million kilometers in space
11:59until it settled in a stable orbit around the Sun.
12:06Kepler's orbit around the Sun
12:14From there it had a fixed and clear view
12:22of a very precise area of the firmament
12:25in the constellation of the swan.
12:36And it exposed its extremely sensitive photometer
12:46to the light of 150,000 stars.
12:57And it began to look for distant worlds similar to Earth.
13:05Kepler's orbit around the Sun
13:24Kepler doesn't detect planets directly.
13:27They are far too small.
13:29They are too small,
13:32and they don't emit light of their own.
13:35They only glow very faintly
13:37reflecting the ambient light of their stars.
13:43So Kepler has to detect planets indirectly.
13:46Imagine that a moth just flew across the light of the lighthouse.
13:53Now, I wouldn't see the moth,
13:55but if I had such a very sensitive detector
13:58and everything was well aligned,
14:00I would see that the intensity of the light dims.
14:04And that's how Kepler detects planets.
14:07If an alien astronomer in a distant solar system
14:10looked at our Sun with the correct alignment,
14:13he would see the trace of the Earth
14:16crossing in front of our star.
14:19He would see that the light of the Sun dims by one hundredth.
14:23It's very little, but it's enough.
14:26And if they saw that dimming was regular,
14:29and it's all done once every year,
14:32then they would infer that there is a planet
14:35orbiting around the star.
14:57Kepler's photometer is extraordinarily sensitive.
15:04But it only sees a regular darkening of pixels.
15:12Even if it's very little data.
15:19Astronomers have begun to build an image of those worlds
15:23that dim the light of the stars.
15:34Worlds that could somehow look like the monster.
15:47Worlds like Kepler-36b.
15:54This planet was one of the first discoveries of the Kepler telescope.
16:08It orbits around a star similar to ours,
16:11so at first glance it's a world that would be familiar to us.
16:16Its mass is four times the mass of the Earth.
16:20And it was one of the first of a new kind of planet.
16:25A super-Earth.
16:46Kepler's data not only allows us to say
16:49that there is a planet around that star,
16:52it also allows us to capture some of its characteristics.
16:55So by looking at the size, weight, light, phase,
16:58and the rise and fall of the light,
17:01and the time at which it dims,
17:04we can measure the orbit of the planets.
17:07And if there are multiple planets in the system,
17:10we can even estimate their masses.
17:13So astronomers can get an idea of the worlds they discover.
17:30But the more detailed our information about the Kepler-36b planet was,
17:34the less this super-Earth looked like our planet.
17:43Kepler-36b
17:48It orbits very close to its star,
17:51going around every 14 days.
18:01And it has company.
18:07A gaseous giant,
18:11that keeps an orbit exceptionally close to its own.
18:17The proximity of its mother star and its brother planet
18:21allows us to imagine the strange conditions
18:24that could be found on the surface of Kepler-36b.
18:29Kepler-36b
18:39It is possible that the planet has a synchronous rotation,
18:43so that an hemisphere would always be oriented towards the star.
18:53The scorching heat of this hemisphere
18:56would melt the ground,
19:03creating lava rivers that would cross the surface.
19:18The planet could experience violent eruptions
19:21when the gravitational pull of the gaseous giant
19:24triggers an extreme volcanism,
19:34every time it passes by.
19:54Kepler-36b
20:02But Kepler-36b could also be an ice planet.
20:16Due to the synchronous rotation,
20:19the other side would be permanently behind the star.
20:25This leads us to imagine an ice hemisphere
20:28enveloped in an eternal darkness.
20:46For now, it's all speculation.
20:50But at least we have begun to create an image of these worlds.
20:54We imagine a world in which the sun
20:57is always placed at the same point in the sky.
21:00One side of the planet would be submerged in an eternal night,
21:04and the other would live an eternal day.
21:07In fact, the twilight strip between day and night
21:11would also suffer from extreme conditions.
21:20So, Kepler-36b demonstrates that the composition of a planet
21:24is not enough for it to be habitable.
21:27You have to take into account the details of its orbit,
21:31and the nature of the other objects in the solar system
21:35that it orbits around its star.
21:49Kepler-36b
21:58Kepler-36b is just one of the thousands of planets
22:02that the Kepler telescope has discovered.
22:11We know without a doubt that in our galaxy
22:14there is a very varied collection of extrasolar worlds.
22:19Kepler-36b
22:25Each one of the more than 4,000 planets discovered so far
22:29is different from all the others.
22:32They all seem strange and exotic to us.
22:35There is certainly no planet that is identical
22:38to the planets in our solar system.
22:41This shows us a deep truth about the universe.
22:45The laws of nature that have formed the planets
22:48are simple and identical everywhere.
22:51And the fundamental ingredients of which the planets are made
22:55are also simple and identical everywhere.
22:58But the nature of a planet also depends on the history of its formation
23:02and the environment that surrounds the mother star from which it was formed.
23:07And those are all totally and absolutely different.
23:12Each planet tells us a different story.
23:15In a way, they are similar to human beings.
23:18And this wholly unexpected and exciting discovery
23:22certainly complicates the search for life.
23:32We need to limit the search for planets
23:37that are not too far from their mother stars.
23:47Planets at the right distance from their surfaces
23:50so that they are habitable.
23:57Distant worlds with a precious ingredient
24:00that makes the Earth a living planet.
24:06Planetary Science
24:23It would be logical to ask ourselves
24:26if we can apply all our knowledge of life on Earth
24:29to planets elsewhere in the universe.
24:32Well, I would say, yes, we can.
24:35Because the laws of nature are universal.
24:38The laws of physics and chemistry that sustain the biology of the Earth
24:42will affect every planet out there in the universe,
24:46whether we discover it or not.
24:56The chemistry of life is based on a few basic ingredients,
24:59carbon, nitrogen, oxygen, and iron.
25:04And it also requires a fast energy supply of good quality,
25:08coming from the heat of the interior of the planets
25:11or the light of the stars.
25:17But life on Earth depends on an extra ingredient,
25:20which is very important, liquid water.
25:23Liquid water is a deceitfully complicated substance.
25:28It's a great solvent, but inside it has structures
25:31that form and disappear constantly,
25:34structures that act as a kind of snap,
25:37around which biology develops.
25:44Organic molecules are aligned in that snap
25:47so that they can react together.
25:51Now, on Earth, all living beings need liquid water to survive,
25:55and I would say this is a very good assumption,
25:58that every living being anywhere in the universe
26:01will require it as well.
26:26In the universe, there is a lot of water.
26:31In our galaxy, large deposits have been discovered,
26:34among the gas clouds of the giant nebulae.
26:41But the abundance of water does not necessarily mean
26:44that it accumulates on planetary surfaces,
26:47forming oceans.
26:51Of the eight planets in our solar system,
26:54there is only one in which liquid water
26:57flows permanently on its surface.
27:04A marine world in which life began a long time ago.
27:11And there is no doubt that there is a lot of water
27:14on the surface of our planet.
27:20And there is no doubt that life began a long time ago.
27:39Around 4 billion years ago,
27:42life on Earth began in places very similar to this,
27:46where there is geothermal activity,
27:49a source of energy in contact with rich concentrations
27:52of reactive minerals and chemical elements.
27:56But also, and this is the fundamental,
27:59there was a magical solvent, liquid water.
28:03Now, many planets in the galaxy
28:06probably have this,
28:09but far few people would think
28:12that large masses of liquid water on the surface.
28:16So that's why in the astrobiological community
28:19the phrase is repeated,
28:22if you want to find life, look for water.
28:40As life evolved on Earth,
28:44at 124 light-years,
28:47in the collapse of a cloud of gas, dust and ice,
28:58a small star was born.
29:07The remains of this star
29:11were condensed and formed a new world.
29:24In 2015, the Kepler telescope
29:27found a planet orbiting relaxedly
29:30in the habitable zone of its star.
29:41Its mass multiplies by 8 the mass of the Earth.
29:44K2-18b is a giant.
29:58And it has a huge gravitational attraction.
30:10If the planet is rocky,
30:13that attraction would have allowed it
30:16to preserve a tense atmosphere.
30:23K2-18b has all the attributes
30:26of an aquatic world.
30:34And a legendary space telescope
30:37brought to light the new discovery of Kepler.
30:46The most powerful of the space telescopes
30:49joined the search.
30:57Hubble inspected the light of the mother star
31:00when K2-18b passed in front of it
31:04and detected what could be a weak indicator
31:07of water vapor.
31:18It is possible that we have finally found
31:21proof of the existence of water
31:24in an extrasolar world,
31:27at 124 light-years from Earth.
31:30This was the first observation
31:33of water vapor in the atmosphere
31:36of a planet orbiting the habitable zone
31:39around its star.
31:42The measurement obtained of the amount
31:45of water vapor is very imprecise.
31:48It oscillates between 0.01 and 50%.
31:51It is very far away.
31:54The important thing is to compare it
31:57The discovery is important for two reasons.
32:00First, it is not zero,
32:03in its atmosphere there is water vapor.
32:06Secondly, if the measurement is in the lower range
32:09and the percentage is low,
32:12it would be compatible with the possibility
32:15that it has oceans on its surface.
32:18At this moment,
32:21there is an intense scientific debate
32:24about the nature of this planet.
32:27It could be a small Neptune,
32:30a gaseous planet.
32:33But we can also dream
32:36of a rocky extrasolar world
32:39with blue skies,
32:42and a dark atmosphere.
32:45A rocky extrasolar world
32:48with sky full of clouds,
32:54where drops of water accumulate
32:57and precipitate,
33:04feeding huge oceans
33:09that cover the surface of a giant planet.
33:16An aquatic world.
33:26A world
33:29where the elixir of life abounds.
33:39K2-18b is exciting.
33:42It is the smallest world with atmosphere
33:45that we have analyzed.
33:48And we found that its mass,
33:51its density and its orbit
33:54are consistent with the possibility
33:57that it is a world with water.
34:00And it might be a world
34:03with oceans on its surface.
34:06We don't know for sure.
34:09K2-18b is orbiting a weak red star.
34:19The Kepler telescope
34:22continued to make many more discoveries.
34:34Until in October 2018,
34:37K2-18b was found without fuel.
34:46In its nine years of activity,
34:49it found more than 2,500 extrasolar worlds.
34:59And it showed us that planets
35:02potentially similar to Earth
35:05are very common.
35:17We estimate that in our galaxy
35:20there could be about 20 billion worlds
35:23that are potentially similar to Earth.
35:26That is, rocky planets in the habitable area
35:29around the star
35:32that is 20 billion potential homes for life.
35:47What we don't know is the probability
35:50that life could begin
35:53when the conditions are right on a planet.
35:56We only know the experience of our world.
35:59We know that life on Earth
36:02began as soon as it was possible.
36:05The oceans on the surface
36:08emerged when the Earth ended up deforming and cooled off.
36:11That is to say, although the origin of life
36:14does not seem to be inevitable,
36:17despite the fact that the conditions are right,
36:20it is reasonably likely.
36:23I think there is at least a possibility
36:26that there could be other planets similar to Earth.
36:31But I think there are two questions about life.
36:34One question is about the origin and existence of microbes.
36:37But often when we talk about aliens,
36:40we don't think about microbes,
36:43but about complex and intelligent creatures
36:46with which we could speak.
36:49We think about civilizations.
36:52What is the probability that there are other civilizations
36:55that we don't know?
36:58But there are observations that we find patterns
37:01that we also see in the Milky Way.
37:04And that marbles us to make certain conjectures.
37:25We don't know exactly
37:28how we have become such complex and intelligent creatures.
37:56But we do know for a fact
37:59that life on Earth has not been at this level
38:02since the beginning.
38:05We are the product of a history
38:08that has developed for more than a quarter
38:11of the age of the universe.
38:17From microbes
38:20to a technological civilization
38:23to a global technological civilization
38:26that wants to contact other civilizations.
38:30At least we remain surrounded by silence.
38:33The messages that we have sent to the cosmos
38:36remain unanswered.
38:39And the telescopes that we use to scan the space
38:42in search of extraterrestrial signals
38:45remain undetected.
38:48That does not mean that there are no other civilizations.
38:52But I think the answer to the question of great silence
38:55is here, on Earth.
38:58Because here it took 4 billion years of stability
39:01for a civilization to emerge.
39:04That is a vast amount of time.
39:07And when we look at the other worlds of the Milky Way
39:10we find that stability and time
39:13appear to be very rare commodities.
39:21In 2013, the European Space Agency
39:24launched the Gaia Space Telescope.
39:30Its mission?
39:33To probe the stars of our galaxy,
39:36the Milky Way.
39:39It has mapped thousands of millions of stars.
39:46Each star has a unique location
39:50Each star could be the center
39:53on which alien worlds orbit.
39:59And several patterns have already emerged.
40:02Not all the stars are alone.
40:17Some have company.
40:33And as strange as it may seem,
40:36the Gaia mission has discovered
40:39about a million binary or multiple stellar systems.
40:47We already knew about the existence
40:50of binary and multiple stellar systems.
40:53But we did not know exactly
40:56whether they were common or not.
41:00But now we have a huge amount of high-precision data,
41:03including the data from the Gaia mission,
41:06which tells us that about 50% of the stars similar to the Sun
41:09are in multiple stellar systems.
41:12And for the most massive stars,
41:15the percentage reaches 80%.
41:21And the prevalence of multiple stellar systems in the galaxy,
41:24how does it affect the possibilities
41:27of finding another Earth?
41:31Could there be planets like Earth
41:34in multiple stellar systems?
41:37And in that case, what could be its future?
41:46In 2020, we found a clue.
41:51We discovered a planet the size of Mars,
41:54moving freely through the galaxy.
41:58Let's call it a rebel planet.
42:02Now, if the planets do not form by themselves
42:05in interstellar space,
42:08where does this planet come from?
42:24The dawn.
42:33Illuminated not by one star,
42:40but by two.
42:43Maybe the rebel planet
42:46was born in a nearby binary system.
43:06Subject to the gravitational force of two stars.
43:10Perhaps its orbit was unstable.
43:21And the two stars fought to control their destiny.
43:39In the systems of a single star,
43:42the weak gravitational interactions between planets
43:45can also alter their orbits.
43:48And in a double stellar system,
43:51they are not only subjected to the gravitational force of others,
43:54but also to the attraction,
43:57even stronger than that of another star.
44:00Although a planet between two stars
44:03has a gravitational force,
44:07even if it enters a stable orbit,
44:10it is very likely that it will not remain in it for a long time.
44:13But when it comes to a double stellar system,
44:16there is a very thin line between order and chaos.
44:27Even the slightest changes in the orbit of a planet
44:30can cause drastic changes in the climate.
44:33That is why it is unlikely that the conditions
44:36of the surface of a planet in a double system
44:39remain stable for long enough
44:42for intelligent life to evolve.
44:53And sometimes,
44:56changes in the orbit of a planet
44:59may not be precisely subtle.
45:03For example,
45:06in the case of a planet between two stars,
45:09it is possible that some approach
45:12would give the rebel world
45:15the definitive gravitational kick.
45:33By launching it outside the system
45:36and freeing it
45:39from the clutches of its stars.
46:04To wander on its own.
46:12On a journey across the galaxy.
46:29Far from the heat of its stars.
46:34Any trace of liquid water it had
46:42would have frozen.
46:49And the atmosphere that protected it
46:53would freeze on the surface.
47:08The rebel planet would become like this
47:13in a world without the right conditions for life.
47:17A lonely and drifting planet.
47:28To be detected by us
47:31millions of years later.
47:34A small wandering planet
47:37similar to Earth
47:40that will wander through the darkness
47:44of space for all eternity.
47:58This lonely wandering planet
48:01is not a unique case.
48:04Although very difficult to detect,
48:07it is estimated that there are more than 100 billion of them
48:10It is possible that the rebel planets
48:13are the most common type of planet on the Milky Way.
48:16And although we think that most of them
48:19were expelled from their system shortly after their formation,
48:22it is an indicator that stellar systems
48:25are not always stable places
48:28where complex life has the possibility of evolving
48:31for billions of years.
48:41The search for another planet with life has just begun.
48:49But we have already learned a lot.
48:58We have found our first rocky worlds.
49:01Some in a habitable area
49:04around certain stars.
49:11Some with the possibility of having water
49:14in a liquid state on its surface.
49:17Candidate worlds for future missions
49:20in search of life evidence.
49:28We have also found a huge amount
49:31of strange and mistreated worlds.
49:35Orbiting around violent stars.
49:48And many rebel planets.
49:53Planets where it seems impossible
49:56to exist what we understand by complex life.
50:05Maybe we will find in those worlds
50:08the explanation why our planet,
50:11for the moment,
50:14is still an exception.
50:34Our planet has been largely free
50:37from violence, chaos,
50:40and the constant change
50:43so common in the Milky Way.
50:46We have witnessed a few massive extinctions,
50:49but the chain of life has not been interrupted
50:52at any time since 4 billion years ago.
50:55If that is what is needed
50:58for life to begin and evolve,
51:01then although there could be billions of worlds
51:04after our life began,
51:07there could be billions of worlds
51:10after our life began,
51:13but without civilizations.
51:16But that should be a basic hypothesis.
51:19And given the profound nature of the question,
51:22I believe it would be ridiculous
51:25for us to stop looking inside and outside
51:29because it is possible
51:32that we have glimpsed for the first time
51:35a world beyond the Milky Way.
51:46About 30 million light years
51:49in the spiral arms of the galaxy Remolino.
51:59There is a planet the size of Saturn.
52:09This discovery represents
52:12a progression of our horizon.
52:18The beginning of the search
52:21for extragalactic planets.
52:25I never thought I would see
52:28the discovery of a planet orbiting
52:31around a star in another galaxy.
52:34This opens up the exciting possibility
52:37of exploring not only if we are alone in our galaxy,
52:40but if we are alone in the universe.
52:47The answer to that question is so far in the future
52:50that it is possible
52:53that we will not find it.
52:56But by saying that the question of whether we are alone is profound,
52:59I mean that answering it would teach us
53:02much more about what it means to be human.
53:09With each world we explore,
53:12we become a little more human
53:15because of our ability to lay the foundations
53:18and ask ourselves questions
53:21that we can solve in life.
53:24Asking questions for our children or grandchildren
53:27is a fundamental part of what it means to be human.
53:30It is a fundamental part of what makes us so special
53:33in this little world,
53:36looking at the stars,
53:39whether we are alone or not.
53:515, 4, 3, 2,
53:54engine start, 1, lift off
53:57for the Delta 2 rocket with the Kepler telescope
54:00in search of planets similar to ours.
54:03The joint work of thousands of people
54:06has become a reality.
54:09We have worked together
54:12to create a new world
54:15where we can all come together
54:18and all come together.
54:21Separation completed.
54:24It was so emotional to see that the project
54:27in which they had worked for so many years,
54:30decades, finally go to space
54:33and all that hope and promise all come about through machinery.
54:42The Kepler telescope was an immediate success.
54:45It discovered more than 2,000 new planets
54:48in its first four years of operation.
54:55But in the summer of 2012,
54:58the team faced a challenge that threatened the entire mission.
55:05One of the fundamental elements of the Kepler
55:08are the reaction wheels that rotate
55:11and keep it focused on the objectives,
55:14the same stars without moving
55:17and the telescope has four of those wheels.
55:21It is usual that the gyroscopes of the spacecraft
55:24end up failing,
55:27but we only had a couple of them to spare.
55:32One wheel started to fail.
55:35Three months later, the second failed
55:38and since we needed three,
55:41we used the Kepler wheel.
55:44I was hoping that they would find a way
55:47to work with two gyroscopes and they did.
55:53So very clever people, engineers, scientists,
55:56they said, let's use the solar radiation
55:59as if it were the third wheel.
56:02We'll make it reflect sunlight
56:05and with the other two wheels working,
56:09the tenuous pressure of the solar wind
56:12helped stabilize the telescope.
56:15That was good news, actually.
56:18The Kepler was going to go off and we could feel other stars.
56:21That was a big boost for stellar astronomy.
56:30After four more years of discovery,
56:33they found more than 2,600 planets.
56:38It became our main planet hunter
56:41until the moment.
56:45The sending of the order of the eclipse
56:48was a very sad moment.
56:51Now it is asleep.
56:54It is in orbit around the sun and will remain in orbit.
56:57But as it was launched from Earth,
57:00the orbit will bring it back to us again.
57:03It will visit us in about 40 years
57:06because it taught us a lot about those planets.
57:09They will go up to pick it up and bring it back
57:12to display it in the Air and Space Museum
57:15so we can admire it.
57:37ESOcast is produced by ESO, the European Southern Observatory.
57:42ESO, the European Southern Observatory, is the pre-eminent intergovernmental science and technology organisation in astronomy,
57:47designing, constructing and operating the world's most advanced ground-based telescopes.