Hubbles Canvas_4of6_Cosmic Perspective and Etched in Time
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00:00In the quest to explore the universe, our greatest ally is the Hubble Space Telescope.
00:09No scientific instrument in history has revealed so much or taken us so far.
00:19Perched 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.
00:31Pictures 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.
01:00The Hubble mission is a project of international cooperation between NASA and the European Space Agency.
01:07The Hubble mission is a project of international cooperation between NASA and the European Space Agency.
01:14For most of human history, the night sky was something you looked at.
01:32A jewel-studded canopy that stretched from horizon to horizon.
01:41To our ancestors, this perspective offered no hint of the universe's true depth.
01:52Wherever they looked, the stars seemed equally remote, like glowing dots painted on a distant ceiling.
02:03After the invention of the telescope, humanity experienced a shift in cosmic perspective.
02:09The shift was gradual, but it was profound.
02:12The more the telescope revealed, the more obvious it became that the universe has a third dimension.
02:19Now we understand that when we're looking at the sky, we're really looking into space.
02:27The Hubble Space Telescope is ideal for plumbing the depths of the universe's third dimension.
02:35From its lofty perch high above Earth's atmosphere,
02:39it can see both nearby and distant objects with unwavering clarity.
02:48Its many spectacular images form a visual pathway that leads us from the boundaries of our own planet
02:56to the most distant corners of the cosmos.
03:03That pathway begins with one small step to a rocky satellite
03:08that is large enough to be considered Earth's sister world.
03:15Compared to our lush and watery home, the dry, barren moon hardly seems like a close relative.
03:23But the differences are deceiving.
03:28The Earth and moon share a common origin.
03:33By exploring the moon's ancient surface, scientists can uncover secrets about our own planet.
03:41Scientists can uncover secrets about our own planet's remote past.
03:49The moon also functions as a giant mirror that reflects sunlight in our direction.
03:56Because Hubble's sensitive optics would be damaged by looking at the sun directly,
04:02astronomers have pointed Hubble toward the moon to measure the colors in the sun's reflected light.
04:10At the same time, they opened up Hubble's cameras for a close-up view of our nearest neighbor in space.
04:18Because the moon and Hubble are moving so quickly relative to each other,
04:23the moon is one of the most difficult targets for the space telescope to capture.
04:30A short leap from the moon takes us further into the inner solar system
04:35for a false-color look at the atmosphere of Venus.
04:41Venus is a planetary inferno where a surface that is hot enough to melt lead
04:47is cloaked in dense clouds of sulfuric acid.
04:55In contrast, Mars is a rust-colored desert where liquid water may still trickle beneath the surface
05:03and where someday the past traces of microscopic alien life may yet be found.
05:16Past the orbit of Mars lies the outer solar system, the realm of the gas giant planets,
05:22beginning with Jupiter, the largest of them all.
05:29Jupiter is not a solid world, but a vast globe of liquid hydrogen and helium
05:35more than 300 times the size of Earth.
05:42With astounding clarity, Hubble offers us an ever-changing view
05:46of Jupiter's swirling, multicolored atmosphere.
05:52Now Hubble carries us to the frozen fringe of our solar system,
06:12home to the dwarf planet Pluto and its large moon, Charon.
06:22Pluto is so far away, it has yet to be visited by a planetary probe.
06:28But in 2005, astronomers using the Hubble discovered that Pluto also has two smaller moons,
06:35now called Nix and Hydra.
06:44This discovery was used to construct an artist's impression of what it might be like
06:49to stand on Pluto's surface, where hills tinged by nitrogen frost
06:54are illuminated by the light of three moons.
07:03At such extreme distances from the sun, there is very little light available
07:08to reveal what lies after Pluto.
07:14But Hubble's penetrating eye has revealed an entire population of tiny worlds
07:20lurking in an endless night.
07:26This is Hubble's best glimpse of Eris, an icy world that is larger than Pluto,
07:32but more than twice as distant.
07:39If we could look homeward from Eris, we would find that Earth is already too faint to see,
07:45and the sun is merely the brightest star among many others.
07:53Now the true expanse of our three-dimensional universe begins to sink in.
08:01As we journey deeper, crossing the great ocean of interstellar space,
08:06we discover that our solar system is part of something one million times larger,
08:12a great starry metropolis called the Milky Way Galaxy.
08:26With stars numbering in the hundreds of billions, our galaxy includes nearly everything
08:32our ancient ancestors could see in the night sky, and much, much more.
08:50Compared to our sun, some of the stars we find in the Milky Way are luminous giants,
08:56and thick clouds of gas and dust where they only recently formed.
09:04In one such cloud, so far away its light would take 8,000 years to reach us,
09:10we find what appears to be one of the largest stars in the galaxy.
09:18That is, until the Hubble discovered it is really two stars in one,
09:22which is more than 100 times the mass of our sun.
09:35At the other extreme, Hubble spies a red dwarf star so small and dim it will shine for a trillion years,
09:43throwing its crimson light onto an even smaller companion.
09:50This smaller object is believed to be a brown dwarf,
09:54a tiny ball of gas that is halfway between being a planet and a star.
10:00Brown dwarfs were first hypothesized years ago when they were too faint to be seen from Earth.
10:08Among Hubble's most important achievements is the confirmation
10:12that brown dwarfs exist in great numbers throughout our galaxy.
10:20Some stars are not solitary, but are congregated into giant globular clusters.
10:31Like a swarm of glowing fireflies, the star cluster known as M80 captures Hubble's roving eye.
10:42It was by carefully measuring the distances and distribution of globular clusters like this
10:48that astronomers first discovered the true dimensions of our Milky Way.
10:59We now know it is a great spiral system, a whirling disk of stars, gas and dust so huge
11:07it takes light 100,000 years to cross it.
11:14But just as the solar system was our stepping stone to a much larger reality,
11:20so in turn the entire Milky Way gives way to the unimaginably vast universe that lies beyond.
11:30This is the universe our ancestors, with their two-dimensional perspective of the night sky, could not perceive.
11:44A universe populated by galaxies in the tens of billions, as magnificent as they are diverse.
11:54It is when Hubble looks out at these faraway galaxies
11:58that we begin to appreciate the true scale of our cosmic perspective.
12:05For in the background, behind each great galaxy, Hubble reveals not emptiness,
12:13but an endless corridor showing more and more galaxies stretching back to the limits of our perception.
12:24Today, astronomers estimate that Hubble can peer more than 13 billion light-years into the cosmos.
12:32In such a large volume of space, the possibilities for discovery are staggering.
12:38Hubble has not taken us to the end point of our cosmic perspective,
12:42but rather to the beginning of a new era of exploration,
12:46an era in which the deeper we look, the more we see.
13:02Hubblecast is produced by ESA, the European Southern Observatory.
13:07The Hubble mission is a project of international cooperation between NASA and the European Space Agency.
13:13The Hubble mission is a project of international cooperation between NASA and the European Space Agency.
13:33Hubblecast is produced by ESA, the European Southern Observatory.
13:39The domain of the telescope is the domain of space.
13:43And in a universe like ours, there's plenty of space to go around.
13:52Because it can look so deeply into space,
13:55the Hubble Space Telescope also brings an added dimension to our view of the cosmos.
14:01The dimension of time.
14:06The light that reaches us from the far corners of the universe
14:10takes millions, even billions of years, to cross the great expanse of intergalactic space.
14:16That means the light we see today departed from its source long ago in the ancient past.
14:22We can never see the universe the way it is, only the way it was.
14:27Over short distances, this effect is slight.
14:31Objects in our solar system are so near that their light reaches us with a delay of only minutes or hours.
14:38At such close range, Hubble can easily track dynamic changes as they occur.
14:50Here it captures a comet in the act of breaking up.
14:54Comets spend most of their time at the frigid outskirts of our solar system.
14:59As they dash past the sun, the change in temperature puts the comet's icy nucleus under extreme stress.
15:07In this case, the result is total disintegration.
15:13In 1992, comet Shoemaker-Levy 9 went through a similar breakup
15:19after making a close pass of the planet Jupiter.
15:25Two years later, the train of comet fragments circled back,
15:29one by one plowing into Jupiter's atmosphere in a series of spectacular collisions.
15:41In this ultraviolet view of Jupiter, taken during the wake of the comet,
15:46the vivid, swirling features of Jupiter's atmosphere are muted.
15:52Much more obvious is this small, dark spot,
15:55which is actually the shadow cast by Io, a moon in orbit around Jupiter.
16:02But across the planet's southern hemisphere, Hubble shows a line of dark patches,
16:07formed as the fragments of comet Shoemaker-Levy 9 collide with Jupiter.
16:13The fragments of comet Shoemaker-Levy 9 collided with the rotating planet one after another.
16:21The patches are dark because the dust that the collisions deposited in Jupiter's upper atmosphere
16:27absorbs ultraviolet light.
16:33In the days and weeks that followed, the dust became a marker
16:37that allowed scientists to track the winds in Jupiter's stratosphere.
16:44Beyond our solar system, we no longer see the universe in the here and now.
16:50Many of the stars and glowing clouds of gas revealed by Hubble
16:54are thousands of light-years away from us,
16:57which means we see them as they were thousands of years in the past.
17:13But even at these distances, there is ample evidence of dynamic change through time.
17:28This awe-inspiring Hubble image is the best picture ever taken of the Cone Nebula.
17:36It is a cold, dark pillar of hydrogen gas and dust with a glowing top.
17:45The glow is caused by ultraviolet light from a brilliant star
17:49located just above the edge of the Hubble picture.
17:59The light is steadily pushing on the top of the cloud,
18:03creating a shadow effect underneath.
18:07In time, this pillar will be eaten away by the light,
18:11possibly revealing a nest of newborn stars.
18:18Because we are seeing this nebula as it appeared in the past,
18:22it has already gone through many changes that we have yet to witness.
18:27These changes are advancing on the scale of thousands of years,
18:31too slowly for Hubble to track.
18:43But Hubble can travel in time in a different way
18:47by looking at clusters of young stars that formed millions of years ago
18:52out of clouds of dust and gas similar to the Cone Nebula.
19:02Looking across larger stretches of space,
19:05Hubble's canvas also encompasses longer epochs of time.
19:21Here, two galaxies careen past each other in a near collision.
19:31The smaller of the pair is the size of our own Milky Way galaxy.
19:36As it swings by its larger neighbor,
19:39gravity distorts the small galaxy, stretching out one of its spiral arms.
19:45With this pair of galaxies, nicknamed the Mice,
19:49a collision in progress has flung two long tails of stars
19:53far outside the galaxies where they were born.
20:00The Mice are now moving apart as they travel across the Milky Way.
20:05The Mice are now moving apart as they travel across the Milky Way.
20:10The Mice are now moving apart
20:14after a close encounter 160 million years ago.
20:19Eventually, gravity will halt their separation
20:23and they will fall back together into a grand merger of all their stars.
20:39In another region of space,
20:41we can see the same story carried forward to the next stage.
20:47These are the Antenna Galaxies,
20:49now 900 million years into a spectacular collision
20:53and more than halfway to a total merger.
21:01Here, Hubble offers us the best view yet
21:04of the heart of this astounding interaction.
21:10While the stars of the Antenna Galaxies
21:13are free to fly past each other at high speed,
21:16we find that something different has happened
21:19to all the dust and gas the galaxies carry with them.
21:24Gravity has pulled on this material
21:27and now we see it spilling out into the space between the two galaxies,
21:31where it's ushered in a baby boom of star formation.
21:40Hubble's view shows a glowing network of bright pink nebulosity.
21:45It's the telltale color of glowing hydrogen gas.
21:49It highlights the nurseries where new stars are being born.
21:55In their midst, we also see brand new star clusters
21:58full of hot blue stars that have recently ignited.
22:10But while these dramatic views show us time unfolding in the universe around us,
22:15they portray a universe that is fundamentally identical to the here and now.
22:22Even though Hubble is peering into the past
22:25when it captures the light from these bright galaxies,
22:28it's only probing the recent history of our universe.
22:35But glimmering in the background,
22:37we can find hints of a deeper time
22:40when the universe looked very different than it does now.
22:50In the constellation Draco the dragon,
22:53Hubble comes across a gorgeous spiral galaxy.
22:57Its light took 80 million years to reach us
23:00and it looks very much like the Milky Way,
23:03the galaxy we call home.
23:06But more than 10 times farther away,
23:09Hubble also spots a quasar.
23:12This object is part of a galaxy too,
23:15one that's too faint to show up in this picture except for its center,
23:20which is shining far brighter than any normal galaxy would appear
23:24at such an extreme distance.
23:28Quasars are inhabitants of an earlier period in the universe's history
23:33when giant black holes at the centers of young galaxies
23:36powered brilliant eruptions of energy.
23:42Here, Hubble operates as a time machine,
23:45allowing us to witness a long vanished age.
23:55The same strategy has been used to capture
23:58Hubble's deepest view of the universe to date.
24:02It was created by pointing the Hubble at an empty patch of sky
24:06again and again over a five-month period.
24:11At first there was nothing to see here at all.
24:15No stars within our Milky Way,
24:18no bright galaxies beyond the Milky Way's borders.
24:23But gradually an image began to emerge,
24:26the image of thousands of galaxies
24:29at the very limits of our cosmic horizon,
24:32going back more than 10 billion years into the past.
24:37Like a living fossil, the image reveals what the universe looked like
24:41shortly after the Big Bang,
24:43when star formation began and galaxies were brand new.
24:50As we explore these far-off islands of light,
24:53distant from us in space and time,
24:56it's clear that the galaxies of this era
24:59are not the stately spirals and other forms
25:02that are familiar to us today.
25:05These galaxies are smaller, dustier, and more disturbed.
25:10They are the products of a cosmic construction project
25:14in which gravity builds bigger galaxies out of smaller constituents.
25:19Until now, astronomers have only been able to guess
25:23how the universe as we know it came to be.
25:26Now, thanks to the Hubble, we can watch the process in action,
25:30touring from past to present.
25:32With Hubble as our looking glass,
25:34time is a landscape that stretches before our eyes
25:38and a journey that is just beginning.
25:54Hubblecast is produced by ESA and the European Space Agency
25:58Transcription by ESO, translated by —
26:23Hubblecast is produced by ESO, translated by —