Hubbles Canvas_6of6_Vanishing Points and Still Life
Category
📺
TVTranscript
00:00In the quest to explore the universe, our greatest ally is the Hubble Space Telescope.
00:08No scientific instrument in history has revealed so much or taken us so far.
00:18Perched above the distorting veil of Earth's atmosphere, Hubble sees what we cannot.
00:24Using vivid color to represent scientific data, Hubble paints pictures of unprecedented clarity,
00:30pictures that bridge the domains of art and science,
00:34and form a direct link between the most powerful forces in nature and the human spirit.
00:54Hubblecast is produced by ESA, the European Southern Observatory.
00:59The Hubble mission is a project of international cooperation between NASA and the European Space Agency.
01:18Like the vanishing point in a perspective drawing,
01:22the core of a neighboring galaxy attracts our gaze,
01:26and makes us feel as though we're staring down a deep well with a bright, shining center.
01:33But this illusion conceals an even deeper truth.
01:39Investigations by the Hubble Space Telescope suggest that at the center of most galaxies,
01:45there lies a giant black hole,
01:48a real-life vanishing point into which matter and light can disappear, never to be seen again.
01:57A black hole is a bizarre place where weird physics reigns supreme.
02:04But the force that gives rise to a black hole is the same force
02:08that governs just about everything we see in the universe,
02:12from planets to stars to entire galaxies.
02:17It's gravity.
02:23Located on the outskirts of our own galaxy, the Milky Way,
02:27this is a globular star cluster.
02:32Although it's much smaller than a galaxy,
02:35it's still mind-bogglingly huge,
02:38containing hundreds of thousands of individual stars.
02:43Held together by their mutual gravity,
02:46these stars have arranged themselves into a perfectly spherical cloud.
02:52On a smaller scale, gravity is the force that brings atoms together
02:57to make stars and planets.
03:01These objects look round because a sphere is the smallest volume
03:05into which a given amount of matter can be packed.
03:11The mass of a star is the same as the mass of a planet.
03:15Matter is the smallest volume into which a given amount of matter can be packed.
03:23And the more matter available,
03:25the stronger the force of gravity that pulls it all together.
03:36Among the nearest stars to Earth is Sirius,
03:39the brightest star in the night sky.
03:43It's sometimes called the Dog Star
03:45because it belongs to the constellation Canis Major,
03:49the faithful canine companion to Orion the Hunter.
03:56Looking at Sirius up close,
03:58the Hubble shows us that the Dog Star has a companion of its own.
04:07Known as Sirius B,
04:09this tiny star is an example of what gravity can do
04:13under more extreme circumstances.
04:17Astonishingly, Sirius B contains as much mass as our Sun,
04:22yet it is no larger than Earth.
04:28This has happened because Sirius B is a dead star.
04:33When its energy ran out, gravity took over
04:36and compressed its atoms into an ultra-dense state known as a white dwarf.
04:50Elsewhere in the universe,
04:52gravity makes possible even more extreme states of matter.
04:59For example, the violent supernova explosions
05:02that mark the deaths of the brightest stars
05:05will unleash enough energy to create neutron stars.
05:13In a neutron star, atoms are crushed together
05:16to form an object 10 trillion times as dense as solid lead.
05:24A typical neutron star contains nearly twice the mass of our Sun,
05:29yet it is no larger than a small city.
05:36Because they are so small, neutron stars are very faint.
05:42Yet with its eagle eye,
05:44Hubble can spot a lone neutron star adrift in interstellar space.
06:06Since a supernova can produce a neutron star,
06:10it makes sense to search for one
06:13where a supernova has occurred in the recent past.
06:17In 1987, a supernova lit up the skies of the Southern Hemisphere.
06:23When Hubble was launched a few years later,
06:26astronomers were eager to observe the aftermath.
06:30What they found,
06:32nestled in this rose-colored cloud of interstellar gas,
06:36was a strange and remarkable sight.
06:40At the very center of this image
06:43is the exploding fireball of the supernova.
06:47But it's encircled by a bright ring of material
06:50that was released before the star exploded.
07:00Over a ten-year period, Hubble has watched this ring brighten
07:04as it's heated by the expanding shockwave from the supernova.
07:11In a universe where change is typically measured over millions of years,
07:15Hubble has given astronomers a rare gift,
07:18front-row seats to a stellar explosion in progress.
07:25And like a cosmic Christmas wreath,
07:27the ring is now aglow with supernova energy.
07:32It's here in the center that astronomers have been looking for the neutron star,
07:36but so far it hasn't appeared.
07:39Perhaps the neutron star is still concealed in enveloping layers of dust.
07:44Or perhaps the size and gravity of the star that went supernova
07:48was enough to create something else,
07:51a black hole.
07:54When matter can no longer resist the relentless pull of gravity,
07:58it forms a black hole,
08:01a region of space where the gravitational field is so strong,
08:05not even light can escape.
08:24To encounter such an object adrift in space
08:27would be to see nothing at all,
08:30except the light of background stars bent by gravity
08:34around the edges of the black hole's event horizon.
08:42Even more intriguing is evidence that at the center of our galaxy
08:46there lurks a black hole of gigantic proportions.
08:51The giant black hole is not visible to the Hubble
08:55because it lies concealed behind the dark dust
08:58that screens the central region of the Milky Way
09:01from our direct line of sight.
09:06So to hunt for giant black holes,
09:09Hubble must turn to other nearby galaxies
09:12where it can peer directly into their central regions.
09:21This is the Andromeda galaxy,
09:24a vast, swirling metropolis of stars
09:27that is twice the size of the Milky Way.
09:32A decade ago, astronomers were puzzled by a strange bluish light
09:36that seemed to come from the very center of Andromeda.
09:41With Hubble's help,
09:43they have now solved the mystery of the blue light.
09:47It is produced by hundreds of bright blue stars
09:50wheeling around Andromeda's center
09:53at speeds approaching 20 million miles
09:56or 32 million kilometers per hour.
10:05Only the powerful attraction of a giant black hole
10:09could force stars to race so quickly.
10:18Even further away than Andromeda,
10:21in the galaxy Centaurus A,
10:23Hubble finds more direct evidence
10:25for the existence of giant black holes.
10:30This galaxy is surrounded by a ring of dark dust,
10:33dust that was acquired from a smaller galaxy
10:36that merged with Centaurus A long ago.
10:39A classic case of galactic cannibalism.
10:44Looking deeper into the partly obscured heart of Centaurus A,
10:49Hubble unveils what astronomers once could only imagine.
10:53A glowing core where gas from the cannibalized galaxy
10:57is feeding a giant black hole.
11:01Unlike the black hole at the center of our Milky Way,
11:05this object is active and obvious.
11:08And when Hubble switches to an infrared view,
11:11it directly sights the vast disk of material
11:14swirling around the black hole.
11:30As Hubble turns its roving eye elsewhere,
11:33increasingly it finds that giant black holes
11:36are a common feature at the centers of many large galaxies,
11:40including galaxies like our own.
11:46And though these black holes ultimately destroy what they devour,
11:50Hubble's exploration of them
11:52has left us with a surprising revelation.
11:56These mysterious and terrifying monsters,
11:59the universe's vanishing points,
12:01may have played a critical role
12:03in the formation of the galaxies that surround them.
12:06If so, they are key components of Hubble's universe,
12:10a universe that not only offers great beauty,
12:13but that also populates itself with curious creatures
12:17who can ponder the remarkable circumstances
12:20of their own existence.
12:37Hubblecast is produced by ESA and the European Southern Observatory
12:40at the European Southern Observatory in Germany.
12:43The Hubble mission is a project of international cooperation
12:46between NASA and the European Southern Observatory.
12:49The Hubble mission is a project of international cooperation
12:52between NASA and the European Southern Observatory.
12:55Transcription by ESO, translation by —
13:07Spreading before us like a giant canvas,
13:10the universe revealed by the artful eye of the Hubble Space Telescope
13:14is a universe of opposites.
13:22At one extreme, the stars burn white-hot,
13:25sometimes illuminating colorful clouds of interstellar gas
13:29with their high-temperature glow.
13:37At the other extreme,
13:39the darkness between the stars is a frigid vacuum,
13:43a space so empty we would need to scour
13:47one million cubic miles, or four million cubic kilometers,
13:51to find enough atoms to make a single drop of water.
13:57At first glance, these extremes of light and dark
14:01do not seem to offer much hope for a life in the universe.
14:06The stars are too hot,
14:08and space is too cold for life to exist.
14:12But fortunately for us,
14:14there is more to this picture than meets the eye.
14:25Planets that orbit around the stars
14:27offer the promise of a middle ground
14:30between the universe's two extremes,
14:33a habitable zone where life can gain a foothold.
14:49Our own solar system is the starting point
14:52in our understanding of how and where life can emerge in the universe.
14:57Here we find a diverse family of planets,
15:01ranging from small and rocky to large and gaseous.
15:14We also find that on at least one of those planets, Earth,
15:19conditions are just right for life to flourish in abundance.
15:24The small fraction of the sun's energy
15:27that splashes onto our world
15:29is just the right amount for water to exist as a liquid.
15:34And that same energy sustains millions of species of plants,
15:38animals, and microbes.
15:46Elsewhere across the galaxy,
15:48we find the building blocks for planets and for life
15:51scattered among the stars.
15:59It's natural to wonder how much life could there be in the universe
16:03and where should we look for the planets that can support it.
16:07These are not just fundamental questions of science,
16:10but questions that lie at the heart of our own sense
16:13of what it means to be alive in a vast and mysterious universe.
16:21Only recently have astronomers had the tools
16:24to begin the search for life in the universe.
16:27And among the most powerful tools of all is the Hubble Space Telescope.
16:33Like other telescopes, Hubble faces a serious challenge.
16:38To search for life, astronomers must search for planets around other stars.
16:43But even for Hubble, those planets are too faint to see directly.
16:48Instead, Hubble has found clues that reveal
16:51how and where planets form in our Milky Way galaxy.
16:57The birthplaces of new planets are the same places
17:00where we can see stars in the making.
17:04They are towering clouds of dust and gas,
17:08where material is gradually pulled together by the force of gravity.
17:22Cloaked behind a veil of dust,
17:24hydrogen and other atoms begin gathering inside the clouds.
17:29As they grow more concentrated, they pull in more material
17:33until the entire cloud coalesces into a cluster of infant stars.
17:46Powered by nuclear energy, young stars can shine with a light so intense
17:51it pushes aside the cocoons where they were born.
17:56And as the dusty veils are lifted,
17:58Hubble gives us a front row seat to the creation of new worlds.
18:11The Orion Nebula is the nearest star-forming region in our galaxy,
18:16and so it gives us the best chance of seeing
18:18how new stars give rise to new planets.
18:24In its central region, a quartet of stars shines with the light of 10,000 suns.
18:30Together, these bright stars have formed a hollow cavity
18:34within the Orion Nebula, allowing astronomers to peer inside.
18:40What they have found is a large population of freshly minted stars,
18:45and also something more.
18:51Many of the stars at the center of the nebula
18:53are surrounded by leftover material from star formation.
19:01This includes dust, which is easily spotted because it absorbs light
19:06and appears dark against the background glow of energized gas.
19:16In example after example, we find that rotation and gravity
19:21have acted together to shape the dusty material
19:24into flat disks that swirl around their stars.
19:30Over a period of tens of millions of years,
19:33the material within these disks will eventually start clumping together
19:37to form planets.
19:46Astronomers have long suspected that solar systems form this way,
19:51but only with Hubble have they been able to capture the process in action.
20:00To gain further insight into the story of planet formation,
20:04astronomers have focused their attention closer to home,
20:07using Hubble's resolving power to search for disks around nearby stars.
20:15In this image, the light of a star similar to our own sun
20:19was artificially blocked by Hubble's camera.
20:22This allows the space telescope to discern a faint reddish glow around the star,
20:29a glow that is caused by a surrounding disk of dust.
20:40The dust particles that are responsible for the glow are tiny,
20:44like particles of smoke.
20:46But buried within the disk, astronomers suspect there are larger clumps,
20:51the building blocks from which planets can form.
21:00Here Hubble discovers what at first glance appears to be a giant eye in space.
21:06This is Fomalhaut, a bright star located in the same part of the Milky Way galaxy
21:11as our own solar system.
21:14Once again, the star's light is artificially blocked
21:17to reveal the faint light of surrounding dust.
21:20But here the dust appears as a narrow ring.
21:25The ring is a strong clue that a planet has formed around Fomalhaut.
21:31As this illustration shows, the planet likely orbits just inside the ring,
21:36where it's in the process of sweeping up dusty material.
21:42Meanwhile, Beta Pictoris, another nearby star,
21:48offers a different angle on planet formation.
21:58Here a dusty disk is seen almost exactly edge-on.
22:03This is Hubble's sharpest view of Beta Pictoris, and it reveals a surprise.
22:08The star is surrounded by two disks rather than one.
22:12A likely explanation for this is that the gravity of a newly formed planet
22:17is disturbing some of the dust that orbits the star, creating a slanted second disk.
22:28Hubble's observations of disks around other stars
22:31have allowed astronomers to see what planet formation looks like from a distance.
22:39It's also been like a time machine that lets us see what the origins
22:43of our own solar system may have looked like four and a half billion years ago.
22:53In a different way, Hubble is also helping to find planets that formed in the past.
22:59To do this, it has stared into the densest part of our Milky Way galaxy,
23:03toward a dust-free region known as the Sagittarius Window.
23:11The result is this dazzling view that contains some 200,000 stars.
23:18The odds are that in a sample this large, many stars will have planets.
23:24And a few of those planets may pass in front of the stars they orbit
23:29just when Hubble is watching.
23:32Sure enough, when Hubble monitored this portion of the sky for seven consecutive days,
23:38it spotted several stars temporarily growing dimmer by a small amount.
23:46In one case, a star dimmed every 10 hours with clock-like precision.
23:54Follow-up observations have confirmed this star is circled by a planet
23:58with roughly the same size and characteristics as Jupiter.
24:09Such a planet is not the kind of world where life as we know it would find a comfortable home.
24:16Nevertheless, this groundbreaking work by Hubble is blazing a trail for future space telescopes,
24:23which will someday be sensitive enough to detect Earth-like planets
24:27as they pass in front of their stars.
24:34By opening the door to the discovery of new worlds,
24:38Hubble is bringing us closer to answering one of the most important questions of human existence.
24:44Are we alone?
24:47Our presence means that we are not just passive spectators of the universe.
24:52As Hubble has now revealed, our planet, like so many others,
24:56has sprung from the raw materials of the universe,
24:59and it's led to our emergence as an exploring species.
25:09This realization gives new meaning to the striking vistas we see spreading before us
25:15as Hubble probes the deepest corners of the cosmos.
25:27What makes the universe so beautiful is not simply the matter and light
25:32that gives rise to such extraordinary variety and detail.
25:36It is the fact that we are here to see it,
25:39the living witnesses that makes this a living universe, a conscious universe,
25:45a universe that can see through the eyes and minds of those that live within it.
26:09Transcription by ESO. Translation by —