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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.
00:57The Hubble mission is a project of international cooperation between NASA and the European Space Agency.
01:18Color is one of the artist's essential tools.
01:23In a painting, color draws the eye and plays on our emotions.
01:32Its effects can be subtle or dramatic.
01:42In astronomy, color serves a different purpose.
01:47When measured precisely, it can tell us about the temperature, chemical composition,
01:53and motion of astronomical objects.
02:00In this way, color can transform a static picture of the night sky
02:06into a detailed portrait of a dynamic and evolving universe.
02:13Like a great artist, the Hubble Space Telescope has become a master of color.
02:21In the process, it has changed the way we see the universe.
02:29Color is so important to the images Hubble provides,
02:33it may come as a surprise to learn that the Hubble's cameras are essentially black and white.
02:40To create the vivid colors we see, Hubble has to image the universe through a variety of filters.
02:47Astronomers then decide how to combine those filters, often to astonishing effect.
02:54Here's how it works.
02:56Each time the Hubble looks at an object through a different filter,
03:00it produces a black and white image that corresponds to a particular wavelength of light.
03:07The black and white images can then be assigned colors, like red, green, and blue.
03:15When three or more of these images are combined,
03:19the resulting full-color image can accentuate important scientific details.
03:26Here, ruby red and emerald green allow astronomers to dissect the complex history behind the Cat's Eye Nebula.
03:36A cloud of debris ejected in stages from a dying star.
03:43And by using color in different ways, Hubble not only gains new information,
03:49it reveals a natural wonder of staggering beauty.
03:57Depending on which filters are chosen, Hubble can recreate the way an object would appear to the human eye.
04:05Like this view of the planet Saturn, with its cream-colored cloud tops and its icy white rings.
04:13But here, Hubble shows us Saturn as we've never seen it before,
04:18with different colors representing the light that comes from different layers in Saturn's atmosphere.
04:26In this case, Hubble's strategic use of color has turned a flat picture
04:31into a three-dimensional voyage to another world.
04:42One kind of information that color can reveal is temperature.
04:47In this young star cluster, all the stars formed together, and so they are all the same age.
04:55But some stars have exhausted their fuel so quickly, they have already expanded and cooled.
05:03The red light they give off indicates a lower temperature.
05:08Meanwhile, the hottest stars in the cluster shine a radiant blue.
05:15Like an exploding rainbow, Hubble's view of the bizarre Egg Nebula reveals what no other telescope can.
05:27At the center of the nebula, an aging star is repeatedly expelling material into space.
05:35The material forms a series of dusty shapes,
05:41The material forms a series of dusty shells nested one inside the other.
05:48Hubble can view the shells as though through a pair of polarized sunglasses,
05:53with different colors representing light that has been reflected and aligned in different directions by the dust.
06:02The results provide astronomers with a detailed picture of how the dust is distributed.
06:11Hubble's powers of perception extend beyond the spectrum of colors that our eyes can see.
06:19Here the telescope uses ultraviolet light to witness the unfolding of a spectacular display of aurora
06:26flickering around Saturn's south pole.
06:32Without Hubble, we would never see views like this.
06:40As much as Hubble can reveal on its own, it can reveal even more when it works in concert with other instruments
06:47like the Hubble Space Telescope.
06:53As much as Hubble can reveal on its own, it can reveal even more when it works in concert with other instruments
07:01that view the universe at drastically different wavelengths.
07:06Together with the Chandra X-ray Observatory and the Spitzer Space Telescope, which sees deep into the infrared,
07:13Hubble leads a fleet of orbiting explorers which has opened our eyes to the full spectrum of information arriving from deep space.
07:28For example, these ragged patches of glowing gas seem to be all that remain from a supernova
07:35that was recorded by the astronomer Johannes Kepler in 1604.
07:44The brightest areas mark the crest of a powerful shock wave that's moving outward from the site of the explosion.
07:53But now Hubble's view is combined with data from the Chandra X-ray Observatory
07:59and the infrared-sensitive Spitzer Space Telescope.
08:04It's clear that there is much more to the explosion's aftermath than meets the eye.
08:13The X-rays show the hot gas in the wake of the shock wave,
08:18while the infrared shows a warm glow from dust particles that were heated by the supernova.
08:28This kind of composite view is incredibly useful for astronomers because it contains multiple layers of information.
08:36Here it helps us to understand how new atoms are forged in the fiery furnace of a supernova explosion,
08:43atoms that could someday become part of future solar systems and even new forms of life.
08:52On a much larger scale, Hubble can also team up with other instruments
08:57to discern powerful forces at work in remote corners of the universe.
09:04The light from this cluster of galaxies takes more than two and a half billion years to reach Earth.
09:12As seen by the Hubble alone, these galaxies look timeless and serene.
09:19When Chandra looks at the same cluster,
09:22it finds that the galaxies are embedded in a cloud of high-temperature gas that's emitting X-rays.
09:30And there is a further mystery.
09:33The gas cloud contains two hollow cavities on either side of the cluster's bright center.
09:42Finally, a third view, created with ground-based radio telescopes, reveals the answer.
09:49It shows two jets of high-speed particles
09:53that have been ejected from the cluster's largest and brightest galaxy.
09:58The particles are moving at nearly the speed of light,
10:01pushing aside the hot gas and carving out the two cavities.
10:07The energies involved here are unimaginable
10:11and could only have been unleashed by a giant black hole.
10:17This lurking beast is too far away for even Hubble to observe directly.
10:23But the power of Hubble, combined with other instruments,
10:27has allowed us to understand the awesome forces at work in this far-away cluster of galaxies.
10:36It's not just the universe.
10:39It's not just the universe's most extreme and violent places
10:42that are best explored with a combination of telescopes spanning the full spectrum of light.
10:49This is one of the crown jewels of the night sky.
10:58Nicknamed the Sombrero Galaxy, it is too near and too far away to be seen.
11:04Nicknamed the Sombrero Galaxy, it is too near and too large to fit into one Hubble telescope image.
11:13Instead, this portrait is a mosaic made of six separate Hubble images.
11:22The Sombrero gets its name from the dark brim of dust
11:26that hides the regions where new stars are being born.
11:32But by adding infrared data from the Spitzer Space Telescope,
11:37the dark dust is transformed into a glowing red ring.
11:45This incredible view drastically improves the clarity
11:49with which we can see into the interior of the galaxy.
12:02Everywhere that Hubble sees color,
12:05it has the potential to reveal new information about the universe.
12:17In this sweeping view, Hubble clearly finds that some galaxies are more red than others.
12:24This has nothing to do with temperature or with chemical composition.
12:32Instead, it's the expansion of the universe itself
12:36that makes the light from extremely distant objects in space appear red.
12:42Astronomers call it the redshift.
12:50Discovered nearly a century ago,
12:53the redshift is our key to measuring how far away galaxies are
12:58and how fast the universe is expanding.
13:06With Hubble, astronomers have made these measurements with unprecedented accuracy.
13:15In space, as in art, color tells a story.
13:22With the Hubble, astronomers have a storyteller like no other.
13:28Hubblecast is produced by ESA, the European Southern Observatory.
13:31The Hubble mission is a project of international cooperation
13:34between NASA and the European Space Agency.
13:37The Hubble mission is a project of international cooperation
13:40between NASA and the European Space Agency.
13:44Hubblecast is produced by ESA, the European Southern Observatory.
13:48The Hubble mission is a project of international cooperation
13:51between NASA and the European Space Agency.
13:55Like great art, the Hubble Space Telescope can capture the things that touch us most deeply,
14:01from birth to death to epic battles.
14:04The difference, of course, is that with Hubble, the battles play out on a galactic scale,
14:09and the result is always a feast for the eyes.
14:13Hubblecast is produced by ESA, the European Southern Observatory.
14:16The Hubble mission is a project of international cooperation
14:19between NASA and the European Space Agency.
14:23Two nearby galaxies adrift against the endless void of space,
14:28each one a sprawling city of stars.
14:33Like ships in the night, they seem to be passing by one another,
14:38but such encounters are not without consequence.
14:43The larger of the two galaxies is a majestic spiral,
14:47similar in size and appearance to our own galaxy, the Milky Way.
14:53It contains hundreds of billions of stars,
14:57and enough matter to wreak havoc on its smaller neighbor.
15:01That neighbor is just a short hop away by cosmic standards,
15:06but it's curiously different from the first galaxy.
15:11A ground-based telescope can show both galaxies in the same field of view,
15:17but it takes Hubble to zoom in on the smaller object,
15:21revealing an incredible sight.
15:24For here is a galaxy that seems to be exploding before our very eyes.
15:33Triggered by the gravitational pull of the larger galaxy next door,
15:38the dormant clouds of hydrogen gas in the smaller galaxy
15:42are collapsing to produce new stars at an astounding rate.
15:48In its central regions, the entire galaxy seems to be on fire
15:53with the energy of thousands of newborn suns.
16:03With a clearer view than any other telescope,
16:06Hubble reveals the streamers of hydrogen gas
16:09flowing outward from the galaxy's center
16:12as they are carried on winds of high-energy particles.
16:24To complete the picture of this exotic galaxy,
16:28astronomers take the Hubble image and add information
16:32that Hubble alone cannot see,
16:35including infrared and X-ray emissions.
16:41When viewed collectively, we are witness to a scene of power and violence
16:46far beyond all human experience,
16:49a cosmic inferno that staggers the imagination.
17:05We do not have to look far to find energy and chaos in the universe.
17:11We can even find it in the spiral arms of our own Milky Way galaxy
17:16by peering into places like the Eta Carinae Nebula,
17:20a colorful jewel of the southern sky.
17:26Seen through Hubble's penetrating eye,
17:29this magnificent formation appears as a great expanse of turbulent gas
17:34where new stars have been under construction
17:37for the past three million years.
17:41The brightest of these stars illuminate the nebula with their intense radiation
17:47and push at the gas and dust to create a cloudscape
17:51that gives the impression of a storm-tossed sea.
17:59Wherever Hubble looks in the Carinae Nebula,
18:02the interaction between matter and energy creates vivid forms
18:06that speak to us about the genesis of stars.
18:13In some places, radiation eats away
18:16at the dustier portions of the star-forming cloud,
18:20creating long peninsulas of dense material that resist the erosion.
18:26In some cases, the peninsulas have turned into free-floating islands
18:31that are the cocoons of new stars and new solar systems.
18:47But amid these new beginnings are the hints
18:50that violent endings will soon follow.
18:56With so much material available for star formation,
19:00some of the stars that are created in the Eta Carinae Nebula
19:04quickly become overgrown beasts
19:06containing 50 to 100 times the mass of our own Sun.
19:12About a dozen such monsters exist today inside the nebula,
19:17none larger than Eta Carinae itself.
19:22In the 1840s, astronomers saw this star flare up
19:27to become one of the brightest stars in the night sky.
19:31Now, over a century and a half later,
19:34Hubble has become the first telescope to show us exactly why.
19:39Although Eta Carinae is a brand-new star in celestial terms,
19:44a few million years old at the most,
19:47it is already starting to blow itself apart.
19:52Zooming in for a closer look,
19:55Hubble detects two giant lobes of material
19:58exploding outward like twin mushroom clouds.
20:05It was the ejection of these clouds
20:08that caused the most recent brightening of Eta Carinae,
20:11and it is likely just the prelude to a far more spectacular death
20:16when Eta Carinae ends its life by going supernova.
20:32A supernova is among the rarest
20:35and most spectacular sights in the universe,
20:39and one upon which our very existence depends.
20:46When a massive star tears itself apart,
20:49it can unleash the energy required to create new atoms.
20:55Here on Earth, every ounce of gold in a pharaoh's tomb,
20:59every speck of uranium in a nuclear reactor,
21:02every inch of copper in every electrical wire on the planet
21:07came into being in the furnace of some long-forgotten supernova.
21:13In the aftermath of this cataclysmic finale,
21:17these precious atoms are scattered far and wide,
21:21eventually to become the building blocks of new stars and planets.
21:34By observing the nearest examples of past supernova explosions,
21:39Hubble is helping to probe the nature and distribution of matter in space
21:45and track the way atoms forged in the death of one star
21:49are eventually cast out into the galaxy
21:52to become the seeds of new solar systems.
22:00Less than 400 years ago,
22:03the last supernova to rattle our corner of the Milky Way
22:07erupted in the direction of the constellation Cassiopeia.
22:14Because the supernova was hidden behind dense clouds of dust,
22:18the event was not noticed by astronomers of the time.
22:26Centuries later, Hubble provides our best view ever
22:30of the expanding shell of debris from this explosive grand finale.
22:36It is an enormous structure,
22:39more than 15,000 times the diameter of our solar system,
22:43and still growing.
23:06For sheer beauty,
23:09nothing can match this dazzling Hubble close-up of the Crab Nebula,
23:13the beautiful remnant of a supernova that exploded nearly 1,000 years ago.
23:21Delicate tendrils of matter from the explosion
23:24reach outward into the surrounding space.
23:30These are the visible layers of matter
23:34These are the visible signs of the rich cosmic chemistry
23:38at work inside the nebula,
23:40which is full of atoms that are key to creating new worlds and new life.
23:48Looking deeper, Hubble also allows us to glimpse
23:52a much more exotic form of matter.
23:58Here, at the center of the Crab Nebula,
24:01we find evidence of the collapsed core of the star
24:04that went supernova long ago.
24:10More massive than our Sun,
24:12this bizarre object is now much smaller than Earth.
24:17Astronomers call it a neutron star,
24:20an object so dense,
24:22its very atoms have been crushed out of existence.
24:27This time-lapse view reveals the concentric rings of material
24:32swirling around the neutron star,
24:35which itself is spinning at the frantic rate of 38 times per second.
24:47This is what happens to matter
24:49when the laws of physics are pushed to their limits.
24:54Thanks to Hubble, the Crab Nebula and other spectacular explosions
24:58that mark the deaths of the brightest stars
25:01can be captured and studied like great works of art.
25:04These violent endings are our chance to see nature at its most extreme,
25:09and they lead us into unknown territory
25:12where scientific theories of matter, energy, space and time are challenged.
25:19This is ultimately why Hubble is so important
25:23and so much like an artist loose among the stars.
25:29It doesn't just change the way we see the universe,
25:32it changes the way we think about it.
25:48Hubblecast is produced by ESA and the European Space Agency
25:51Transcription by ESO, translated by —
26:18www.spacetelescope.org

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