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SUB BY : DENI AUROR@
https://aurorarental.blogspot.com/
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Neutron stars.
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Super heavy, super dense.
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Extreme.
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Gravitational, magnetic, hot.
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Scary.
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They destroy planets.
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They can even destroy stars.
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A cosmic conundrum.
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They're very, very massive,
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but they're also really, really small.
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Tiny cosmic super powers
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long overshadowed by black holes ...
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until now.
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Neutron stars have been thrust very much
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to the forefront of modern astrophysics.
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The world's astronomers know that something is happening.
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Something's up, it's new, and it's different.
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Neutron stars are the most interesting
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astrophysical object in the universe.
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Now firmly in the limelight,
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neutron stars, creators of our most precious elements
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and life itself.
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captions paid for by discovery communications
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130 million light years form earth,
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a galaxy called "ngc-4993."
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Two dead stars trapped in a rapidly diminishing spiral.
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It's like listening to the ringing of the cosmos itself.
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The sound of that collision, if you will,
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imprinted on the fabric of space and time itself.
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Livingston, Louisiana, the advanced ligo observatory.
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Its mission ... to detect gravitational waves
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generated in space.
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A gravitational wave is a distortion of space time
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that's caused by, usually,
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some kind of very traumatic gravitational event.
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Events such as a supernova,
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or the collision of black holes, or massive stars.
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2015 ... ligo makes history by detecting gravitational waves
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for the first time,
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100 years after Einstein's prediction.
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It's the signature of the crash of black holes.
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It's almost like listening to the sound
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of a distant car crash that you didn't witness.
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But you're so clever,
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and the sound of this car crash is such a unique signature,
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that you are able to use your computers to model
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exactly the type of cars that must have collided together.
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In 2017, ligo picks up a different
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kind of signal.
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The unfolding of the August 2017 event
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was nothing short of extraordinary.
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So, the signal comes in, and the signal is strange.
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It has a long-lasting signal.
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It's over 100 seconds.
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Less than two seconds later, a gamma-ray telescope
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detected a flash of gamma rays
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from that same part of the sky.
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And very quickly, the world's astronomers
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know that something is happening.
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Something's up, it's new, and it's different.
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This combination of a long gravitational wave signal
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and a Blaze of gamma rays...
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Acts as a beacon for astronomers.
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When they saw this event,
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they sent out a worldwide alert
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to astronomers across the globe, saying,
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"hey, we saw something interesting,
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and it came from a particular patch of sky.
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Then, all the chatter started
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amongst the astronomical community,
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and everyone starting pointing their telescopes
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at this one part of the sky.
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Within hours, thousands of astronomers
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and physicists across the globe are frantically
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collecting data on this mysterious event.
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There is not just the gravitational waves,
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there is not just the gamma rays.
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There's a visible light, there's infrared light,
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there's ultraviolet light.
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And all these signals together tell us a story.
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And this was the very first time
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we've seen these two multiple messengers at once ...
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gravitational waves and regular light.
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So, that was a groundbreaking moment for astronomy.
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Scientists realize
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this isn't another black-hole collision.
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This is something different.
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When you see an explosion in the universe,
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there aren't exactly a lot of candidates.
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There's not a lot of things in the universe that blow up.
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But the length of the signal is the smoking gun.
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The collision of two black holes was quick.
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This one was the longer, slower, death end-spiral
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of two neutron stars.
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Spiraling in, closer and closer, speeding up.
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And then, when they finally collide,
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when they finally touch, releasing a tremendous
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amount of energy into the surrounding system.
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The collision throws up huge clouds of matter,
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which may have slowed down the light very slightly.
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The light and gravitational waves
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travel for 130 million years,
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arriving at earth almost simultaneously.
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It's the first time astronomers see neutron stars collide.
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They call it a "kilonova."
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And this spectacular cosmic event
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doesn't just release energy.
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The aftermath of this neutron-star collision,
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this kilonova, created a tremendous amount of debris,
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which blasted out into space.
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And this may finally have provided us
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the evidence of where some very special
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heavy elements are created.
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Through the destruction of a neutron star comes the seeds
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for the essential ingredients of life itself.
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We breathe oxygen molecules ... O2.
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Water is hydrogen and oxygen.
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Most of our body is made up of carbon compounds
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that include nitrogen, phosphorus.
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One of the big questions in science
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over the history of humanity has been,
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"what are the origins of these elements?"
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And it turns out that neutron stars play a critical role
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in creating many of the heavy elements.
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Most of the elements on earth are made in stars.
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But how the heaviest elements are made
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has been one of science's longest-running mysteries.
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For a long time, we knew there was a problem
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with making these heavier atoms ...
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things like gold and platinum, all the way out towards uranium.
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And really, the most energetic thing we had
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in the universe was supernova explosions.
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So, they had to be created somehow in supernovas.
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But when scientists ran computer simulations,
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virtual supernovas failed to forge these oversized atoms.
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In 2016, astronomer edo berger explained
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a potential solution to the mystery.
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Berger: If you open any one of these books,
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and flip to the page that tells you where gold came from,
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it will tell you that gold came from supernova explosions.
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But it was becoming clear that the textbooks were out of date.
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berger: To form heavy elements requires a lot of neutrons,
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and so, another possible theory was that
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the heaviest elements were produced in the mergers
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of two neutron stars in a binary system.
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But at the time, no one had actually seen
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a neutron-star collision.
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It was difficult to convince the community
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that this was a potential channel
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for the production of heavy elements.
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The proof is to actually see this process
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happening in the universe.
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The 2017 kilonova
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provides the perfect opportunity.
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It generates thousands of hours of data.
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Scientists notice a pattern ...
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subtle changes in the color of the kilonova remnants.
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In space, when you have an event that is very bright,
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it emits a certain amount of light,
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and it emits it at certain wavelengths ...
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what we think of as colors.
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Different colors in a pyrotechnics display
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indicate the use of different chemicals in fireworks.
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In the same way, scientists can uncover the elements
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in the kilonova by the colors in the explosion.
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As the kilonova turns red, they realize it's the result
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of newly-created heavy elements
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starting to absorb blue light.
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As we watched this remnant change ...
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the explosion change in color, expand and cool ...
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we could estimate what sort of elements were being produced.
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The light from the debris shifts
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from blue and Violet to red and infrared.
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The color change provides clues
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about the presence of certain heavy metals.
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well, this neutron-star collision, this kilonova,
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produced brightness and a color spectrum
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that are consistent with models of predictions
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that produce gold and platinum.
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This model is called "the r-process,"
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short for "rapid neutron capture."
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That is a bit of a complicated term
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that describes how we make atoms heavier than iron.
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You need a really neutron-rich environment.
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And as you might imagine, a neutron-star collision
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is a very neutron-rich environment.
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If these models are correct ...
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and this blows me away ...
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this collision, this kilonova,
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produced several dozen times the mass of the earth
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in just gold.
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The 2017 kilonova not only reveals
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the origin of key elements,
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it sheds light on the neutron star's interior ...
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the strongest material in the universe
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creating a magnetic field
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a trillion times greater than that of earth.
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Two neutron stars caught in a death spiral.
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This massive kilonova explosion not only sheds light
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on the creation of heavy elements,
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such as gold and platinum,
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it also provides scientists with a unique insight
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into one of the most mysterious objects in the universe.
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Trying to imagine what a neutron star is really like
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really challenges our imagination.
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It also challenges our theoretical physics.
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We have to go to our computer models, our mathematics,
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to have some estimate of what this might be like.
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Now, scientists don't have to rely
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on their imaginations.
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They can use hard data from the kilonova
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to work out what makes neutron stars tick.
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There's so much information we got from observing
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that one single event, that one colliding neutron star pair.
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Now, for the first time, we have an accurate estimate
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of the mass of a neutron star, and the diameter.
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We can finally begin to piece together
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how neutron stars really work.
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They calculate the diameter is just 12.4 miles,
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1 mile less than the length of Manhattan.
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Nailing down any physical characteristic
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is really important.
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And if there's gonna be one,
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the radius is a big one, because from there,
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if you know the mass, you can get the density.
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And if you know the overall density,
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you can start to figure out what the layering
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inside of a neutron star is like.
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For physicists, the interior of a neutron star
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is one of the most intriguing places in the universe.
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Bullock: You have to realize that the conditions
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inside a neutron star are very, very different
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than the conditions that exist here on earth.
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We're talking about material that's so dense
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that even the nuclei of atoms can't hold together.
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With a neutron star, you're taking something
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that weighs more than the sun,
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and compressing it down to be smaller than a city.
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It's so dense that, if you tried to put it on the ground,
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it would fall right through the earth.
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High density means high gravity ...
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gravity 200 billion times greater than on earth.
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Imagine climbing up on a table on the surface
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of a neutron star and jumping off.
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You're gonna just get flattened instantly,
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and just spread out on that surface.
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So, don't even think about trying to do push-ups.
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Added to the intense gravity
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are hugely powerful magnetic fields,
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awesome X-ray radiation,
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electric fields 30 million times more powerful
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than lightning bolts,
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and blizzards of high-energy particles.
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This isn't a good neighborhood for a space traveler.
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Sutter: If you were to find yourself in the vicinity
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of a neutron star, it's gonna be bad news.
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First, you would be torn apart
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by the incredibly strong magnetic fields.
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Then, the X-ray radiation would blast you to a crisp.
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And as it pulled you closer,
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its intense gravity would stretch out
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your atoms and molecules into a long, thin stream.
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You would build your speed faster and faster,
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and then, you would finally impact the surface,
265
00:14:45,952 --> 00:14:47,686
splatter across it.
266
00:14:47,688 --> 00:14:50,755
And that process would release as much energy
267
00:14:50,757 --> 00:14:51,822
as a nuclear bomb.
268
00:14:54,894 --> 00:14:58,095
If I had the choice between falling into a neutron star
269
00:14:58,097 --> 00:15:01,298
versus a black hole, I think I'd pick the black hole.
270
00:15:01,300 --> 00:15:03,501
'Cause I don't really feel like being torn apart
271
00:15:03,503 --> 00:15:06,036
by a magnetic field and blasted with x-rays.
272
00:15:10,509 --> 00:15:15,045
On a cosmic scale, neutron stars may be pint-sized,
273
00:15:15,047 --> 00:15:17,715
but they sure pack a serious punch.
274
00:15:17,717 --> 00:15:20,317
The secret to all this pent-up power
275
00:15:20,319 --> 00:15:24,855
is what's going on below the surface.
276
00:15:24,857 --> 00:15:27,391
Armed with the new kilonova data,
277
00:15:27,393 --> 00:15:29,126
we can now take a virtual journey
278
00:15:29,128 --> 00:15:31,795
into the heart of a neutron star.
279
00:15:31,797 --> 00:15:36,133
First, we must pass through its atmosphere.
280
00:15:36,135 --> 00:15:37,467
Now, it's not like the earth's atmosphere,
281
00:15:37,469 --> 00:15:39,269
which goes up, like, a 100 miles.
282
00:15:39,271 --> 00:15:42,673
On a neutron star, the atmosphere is about this deep,
283
00:15:42,675 --> 00:15:47,945
and it's extremely dense compared to the air around us.
284
00:15:47,947 --> 00:15:52,549
Below the compressed atmosphere is a crust of ionized iron,
285
00:15:52,551 --> 00:15:54,951
a mixture of crystal iron nuclei,
286
00:15:54,953 --> 00:15:58,289
and free-flowing iron electrons.
287
00:15:58,291 --> 00:16:00,357
Now, the gravity's so strong
288
00:16:00,359 --> 00:16:02,560
that it's almost perfectly smooth.
289
00:16:02,562 --> 00:16:04,028
The biggest mountains on the surface
290
00:16:04,030 --> 00:16:06,431
are gonna be less than a quarter of an inch high.
291
00:16:06,433 --> 00:16:11,902
A quarter-inch mountain range may sound odd...
292
00:16:11,904 --> 00:16:16,207
But things get even stranger as we go below the surface.
293
00:16:18,311 --> 00:16:22,279
This is home to the strongest material in the universe.
294
00:16:25,451 --> 00:16:31,522
It's so weird, scientists liken it to nuclear pasta.
295
00:16:31,524 --> 00:16:34,525
Sutter: As we dive beneath the crust of a neutron star,
296
00:16:34,527 --> 00:16:37,861
the neutrons themselves start to glue themselves together
297
00:16:37,863 --> 00:16:39,730
into exotic shapes.
298
00:16:39,732 --> 00:16:45,002
First, they form clumps that look something like gnocchi,
299
00:16:45,004 --> 00:16:48,072
then, deeper, the gnocchi glue themselves together
300
00:16:48,074 --> 00:16:52,142
to form long strands that look like spaghetti.
301
00:16:52,144 --> 00:16:54,678
Even deeper, the spaghetti fuse together
302
00:16:54,680 --> 00:16:58,148
to form sheets of lasagna.
303
00:16:58,150 --> 00:17:01,151
And then, finally, the lasagna fuse together
304
00:17:01,153 --> 00:17:05,689
to become a uniform mass, but with holes in it.
305
00:17:05,691 --> 00:17:08,159
So, it looks like penne.
306
00:17:08,161 --> 00:17:11,629
This is pasta, nuclear style,
307
00:17:11,631 --> 00:17:12,829
simmering at a temperature
308
00:17:12,831 --> 00:17:15,632
of over one million degrees fahrenheit.
309
00:17:15,634 --> 00:17:19,436
Extreme gravity bends, squeezes, stretches,
310
00:17:19,438 --> 00:17:22,372
and buckles neutrons, creating a material
311
00:17:22,374 --> 00:17:26,710
100,000 billion times denser than iron.
312
00:17:26,712 --> 00:17:30,447
But the journey gets even more extreme.
313
00:17:30,449 --> 00:17:34,251
Even deeper is more mysterious and harder to understand.
314
00:17:34,253 --> 00:17:36,320
The core of a neutron star ...
315
00:17:36,322 --> 00:17:39,123
which is very far away from these layers,
316
00:17:39,125 --> 00:17:41,191
which we call the "nuclear pasta" ...
317
00:17:41,193 --> 00:17:44,395
is perhaps the most exotic form of matter.
318
00:17:44,397 --> 00:17:48,665
So exotic it might be the last bastion of matter
319
00:17:48,667 --> 00:17:52,937
before complete gravitational collapse into a black hole.
320
00:17:54,941 --> 00:17:57,274
Data from NASA's chandra observatory
321
00:17:57,276 --> 00:18:00,678
suggests the core is made up of a super fluid ...
322
00:18:00,680 --> 00:18:04,414
a bizarre friction-free state of matter.
323
00:18:04,416 --> 00:18:07,151
Similar super fluids produced in the lab
324
00:18:07,153 --> 00:18:09,086
exhibit strange properties,
325
00:18:09,088 --> 00:18:11,822
such as the ability to flow upwards
326
00:18:11,824 --> 00:18:15,693
and escape airtight containers.
327
00:18:15,695 --> 00:18:18,028
Although our knowledge of the star's interior
328
00:18:18,030 --> 00:18:20,230
is still hazy, there's not mystery
329
00:18:20,232 --> 00:18:22,432
about its dazzling birth.
330
00:18:22,434 --> 00:18:26,503
Forged into life during the most spectacular event
331
00:18:26,505 --> 00:18:28,505
the universe has to offer ...
332
00:18:28,507 --> 00:18:31,910
the explosive death of a massive star.
333
00:18:48,127 --> 00:18:50,127
Neutron stars ...
334
00:18:50,129 --> 00:18:56,800
Manhattan-sized, but with a mass twice that of our sun.
335
00:18:56,802 --> 00:19:02,806
So dense a teaspoon of their matter weighs a billion tons.
336
00:19:02,808 --> 00:19:07,077
Mind-blowing objects that arrive with a bang.
337
00:19:07,079 --> 00:19:09,013
Neutron stars spark into life
338
00:19:09,015 --> 00:19:11,081
amid the death of their parent star.
339
00:19:11,083 --> 00:19:13,684
They're the ultimate story of resurrection,
340
00:19:13,686 --> 00:19:16,353
or of life from death.
341
00:19:16,355 --> 00:19:20,490
It's all part of a cosmic cycle.
342
00:19:20,492 --> 00:19:24,762
Stars are born from giant clouds of very cold gas.
343
00:19:24,764 --> 00:19:27,866
Those clouds collapse under their own gravity,
344
00:19:27,868 --> 00:19:31,034
and the density of the core at the center of the collapse
345
00:19:31,036 --> 00:19:32,169
starts to increase.
346
00:19:37,309 --> 00:19:41,178
A star is a huge nuclear fusion reactor.
347
00:19:41,180 --> 00:19:43,780
The force of its gravity is so powerful
348
00:19:43,782 --> 00:19:45,582
that it fuses atoms together
349
00:19:45,584 --> 00:19:50,454
to make progressively heavier and heavier elements.
350
00:19:50,456 --> 00:19:53,657
The star fuses hydrogen into helium.
351
00:19:53,659 --> 00:19:56,860
Once it exhausts its hydrogen, then, if it's massive enough,
352
00:19:56,862 --> 00:19:59,196
it can start fusing helium at its core.
353
00:20:01,734 --> 00:20:04,401
Fusion continues, forming carbon,
354
00:20:04,403 --> 00:20:10,474
oxygen, nitrogen, all the way up to iron.
355
00:20:10,476 --> 00:20:12,743
Once a star has iron in the core,
356
00:20:12,745 --> 00:20:14,678
it's almost like you've poisoned it,
357
00:20:14,680 --> 00:20:18,414
because this extinguishes the nuclear reactions
358
00:20:18,416 --> 00:20:19,749
in the core of the star.
359
00:20:19,751 --> 00:20:23,954
You fuse something into iron, and you get no energy.
360
00:20:23,956 --> 00:20:25,756
All of a sudden, there's nothing to support
361
00:20:25,758 --> 00:20:27,091
the crush of gravity.
362
00:20:27,093 --> 00:20:28,759
No radiation pressure pushing out
363
00:20:28,761 --> 00:20:32,697
means no pressure keeping the outer regions from falling in,
364
00:20:32,699 --> 00:20:34,565
and that's what they do.
365
00:20:34,567 --> 00:20:37,767
As the star collapses in its death throes,
366
00:20:37,769 --> 00:20:41,171
its core becomes the wildest, craziest,
367
00:20:41,173 --> 00:20:45,375
and freakiest pressure cooker in the whole universe.
368
00:20:47,513 --> 00:20:50,046
The ingredients are all in place.
369
00:20:50,048 --> 00:20:54,853
It's time to start cooking up a neutron star.
370
00:20:54,855 --> 00:20:57,654
If we were to scale up an atomic nucleus
371
00:20:57,656 --> 00:20:59,522
to be the size of a baseball,
372
00:20:59,524 --> 00:21:03,594
in a normal atom, the nearest electron would be
373
00:21:03,596 --> 00:21:05,530
way over in those trees,
374
00:21:05,532 --> 00:21:07,664
but in the extreme conditions that lead to
375
00:21:07,666 --> 00:21:09,867
the formation of a neutron star,
376
00:21:09,869 --> 00:21:13,937
those electrons can be pushed closer to the nucleus.
377
00:21:13,939 --> 00:21:17,073
They can come zipping in from any direction.
378
00:21:17,075 --> 00:21:19,943
And if the temperatures and pressures are high enough,
379
00:21:19,945 --> 00:21:22,012
they can even strike the nucleus
380
00:21:22,014 --> 00:21:24,881
and enter it, and they can hit a proton.
381
00:21:24,883 --> 00:21:29,419
And when they do, they become converted into more neutrons.
382
00:21:29,421 --> 00:21:32,023
So, in the formation of one of these objects,
383
00:21:32,025 --> 00:21:34,424
the protons and electrons disappear,
384
00:21:34,426 --> 00:21:37,360
and you're left with almost entirely pure neutrons,
385
00:21:37,362 --> 00:21:40,430
with nothing to stop them from cramming together
386
00:21:40,432 --> 00:21:43,300
and filling up this entire baseball
387
00:21:43,302 --> 00:21:48,905
with neutrons leading to incredibly high densities.
388
00:21:48,907 --> 00:21:50,307
With the sea of electrons
389
00:21:50,309 --> 00:21:52,776
now absorbed in the atomic nuclei,
390
00:21:52,778 --> 00:21:57,714
the matter in the stars can now press together a lot tighter.
391
00:21:57,716 --> 00:22:00,917
It's like squeezing 300 million tons of mass
392
00:22:00,919 --> 00:22:04,254
into a single sugar cube.
393
00:22:04,256 --> 00:22:06,056
As the star collapses,
394
00:22:06,058 --> 00:22:09,126
enormous amounts of gas fall towards the core.
395
00:22:11,863 --> 00:22:16,399
The core is small in size, but huge in mass.
396
00:22:16,401 --> 00:22:19,203
Billions of tons of gas bounce off of it,
397
00:22:19,205 --> 00:22:22,672
then erupt into the biggest fireworks display
398
00:22:22,674 --> 00:22:25,542
in the cosmos...
399
00:22:25,544 --> 00:22:28,145
A supernova.
400
00:22:28,147 --> 00:22:29,412
It's massive.
401
00:22:29,414 --> 00:22:30,546
It's bright.
402
00:22:30,548 --> 00:22:31,815
It's imposing.
403
00:22:31,817 --> 00:22:34,951
Supernova are among the most dramatic events
404
00:22:34,953 --> 00:22:36,419
to happen in the universe.
405
00:22:36,421 --> 00:22:38,088
A single star dying ...
406
00:22:38,090 --> 00:22:43,061
one star dying ... can outshine an entire galaxy.
407
00:22:46,965 --> 00:22:49,432
And arising out of this cataclysm,
408
00:22:49,434 --> 00:22:52,836
a new and very strange cosmic entity.
409
00:22:55,841 --> 00:22:58,775
When the smoke finally clears from the supernova explosion,
410
00:22:58,777 --> 00:23:01,445
you're left with one of the most real, fascinating,
411
00:23:01,447 --> 00:23:04,580
unbelievable monsters of the entire universe.
412
00:23:04,582 --> 00:23:06,183
Humans have been witnessing supernovas
413
00:23:06,185 --> 00:23:07,851
for thousands of years,
414
00:23:07,853 --> 00:23:10,654
but we're only now just starting to understand
415
00:23:10,656 --> 00:23:13,457
what we've truly been witnessing ...
416
00:23:13,459 --> 00:23:17,327
the births of neutron stars.
417
00:23:17,329 --> 00:23:20,463
But while supernovas are big and bright,
418
00:23:20,465 --> 00:23:23,066
neutron stars are small,
419
00:23:23,068 --> 00:23:26,202
and many don't even give off light.
420
00:23:26,204 --> 00:23:30,141
So, how many neutron stars are out there?
421
00:23:30,143 --> 00:23:33,677
We know of about 2,000 neutron stars in our galaxy,
422
00:23:33,679 --> 00:23:35,279
but there probably are many, many, more.
423
00:23:35,281 --> 00:23:38,148
I'm talking about tens of millions in the milky way alone,
424
00:23:38,150 --> 00:23:42,419
and certainly billions throughout the universe.
425
00:23:42,421 --> 00:23:48,291
Neutron stars may be small, but some give themselves away,
426
00:23:48,293 --> 00:23:51,762
shooting beams across the universe ...
427
00:23:51,764 --> 00:23:56,967
unmistakable, pulsing strobes of a cosmic lighthouse.
428
00:24:16,054 --> 00:24:20,524
Our knowledge of neutron stars is expanding fast.
429
00:24:23,128 --> 00:24:25,263
But we didn't even know they existed
430
00:24:25,265 --> 00:24:28,765
until a lucky discovery just over 50 years ago.
431
00:24:30,803 --> 00:24:34,003
Sutter: Cambridge, the mullard radio observatory,
432
00:24:34,005 --> 00:24:35,939
Jocelyn bell, grad student,
433
00:24:35,941 --> 00:24:39,475
operating the new radio telescope.
434
00:24:39,477 --> 00:24:42,612
Scanning the sky, doing all sorts of cool astronomy stuff,
435
00:24:42,614 --> 00:24:48,017
and sees what she calls "a bit of scruff" in the data.
436
00:24:48,019 --> 00:24:49,419
This scruff is a short
437
00:24:49,421 --> 00:24:52,756
but constantly repeating burst of radiation
438
00:24:52,758 --> 00:24:57,027
originating 1,000 light years from earth.
439
00:24:57,029 --> 00:25:00,296
It's so stable and regular that bell is convinced
440
00:25:00,298 --> 00:25:02,900
there's a fault with her telescope.
441
00:25:02,902 --> 00:25:04,901
She returns to that spot,
442
00:25:04,903 --> 00:25:09,106
and finds a repeating, regular signal ...
443
00:25:09,108 --> 00:25:14,710
a single point in the sky that is flashing at us continually,
444
00:25:14,712 --> 00:25:17,514
saying "hi. Hi. Hi."
445
00:25:17,516 --> 00:25:19,182
Blip, blip, blip.
446
00:25:19,184 --> 00:25:21,518
Boom, boom, boom.
447
00:25:21,520 --> 00:25:23,453
Pulse, pulse, pulse.
448
00:25:23,455 --> 00:25:25,455
Nothing that we know of in the universe,
449
00:25:25,457 --> 00:25:30,059
has such a steady, perfectly-spaced in time, pulse.
450
00:25:30,061 --> 00:25:34,265
It seemed so perfect that it must have been artificial.
451
00:25:34,267 --> 00:25:37,734
It looks like someone is making that,
452
00:25:37,736 --> 00:25:41,671
but it turns out, it's not a person, but a thing.
453
00:25:41,673 --> 00:25:44,475
What she discovered was called a "pulsar."
454
00:25:47,346 --> 00:25:50,013
A pulsar is a type of rapidly spinning
455
00:25:50,015 --> 00:25:51,281
neutron star.
456
00:25:54,086 --> 00:25:57,954
Neutron stars had been theorized in the 1930s,
457
00:25:57,956 --> 00:26:01,892
but were thought to be too faint to be detected.
458
00:26:01,894 --> 00:26:06,429
Neutron stars were hypothesized to exist,
459
00:26:06,431 --> 00:26:09,365
but not really taken seriously.
460
00:26:09,367 --> 00:26:11,902
It was just a, "oh, that's cute.
461
00:26:11,904 --> 00:26:14,404
Maybe they're out there, but probably not."
462
00:26:15,641 --> 00:26:17,440
The signal bell detected
463
00:26:17,442 --> 00:26:21,445
seemed like something from science fiction.
464
00:26:21,447 --> 00:26:24,180
No one had ever seen this in astronomy before,
465
00:26:24,182 --> 00:26:28,319
and some people even speculated that it was an alien signal.
466
00:26:28,321 --> 00:26:30,720
She even called them "lgm objects" ...
467
00:26:30,722 --> 00:26:33,590
"little green men."
468
00:26:33,592 --> 00:26:36,093
But then, bell found a second signal.
469
00:26:38,931 --> 00:26:42,132
Little green men went back to being fiction,
470
00:26:42,134 --> 00:26:45,868
and pulsars became science fact.
471
00:26:45,870 --> 00:26:48,137
The discovery of pulsars came out of the blue.
472
00:26:48,139 --> 00:26:49,739
Nobody was expecting this.
473
00:26:49,741 --> 00:26:51,876
So, it was an amazing breakthrough ...
474
00:26:51,878 --> 00:26:53,076
really important.
475
00:26:56,348 --> 00:27:00,750
Pulsars pulse because they are born to spin.
476
00:27:00,752 --> 00:27:04,821
They burst into life as their parent star collapses
477
00:27:04,823 --> 00:27:06,356
during a supernova.
478
00:27:08,627 --> 00:27:10,961
Any object at all that is undergoing
479
00:27:10,963 --> 00:27:13,095
any sort of compression event,
480
00:27:13,097 --> 00:27:16,299
if it has any initial angular momentum at all,
481
00:27:16,301 --> 00:27:20,503
it will eventually end up spinning.
482
00:27:20,505 --> 00:27:24,508
As the star shrinks, it spins faster and faster.
483
00:27:26,511 --> 00:27:30,647
They spin so quickly because the earth-sized core
484
00:27:30,649 --> 00:27:32,048
of a massive star
485
00:27:32,050 --> 00:27:35,252
collapsed to something as small as a city.
486
00:27:35,254 --> 00:27:39,456
So, because the size of the object became so much smaller,
487
00:27:39,458 --> 00:27:44,127
the rate of spin had to increase by a tremendous amount.
488
00:27:44,129 --> 00:27:47,464
Neutron stars can spin really, really, fast.
489
00:27:47,466 --> 00:27:49,932
Their surface is moving so fast.
490
00:27:49,934 --> 00:27:53,670
It's moving at about 20% the speed of light, in some cases.
491
00:27:53,672 --> 00:27:57,006
Sutter: So, if you were to get on the neutron star ride ...
492
00:27:57,008 --> 00:28:01,077
no pregnant women, no bad backs, no heart issues,
493
00:28:01,079 --> 00:28:03,680
keep your arms and legs inside the ride at all times,
494
00:28:03,682 --> 00:28:05,950
because they are about to be obliterated.
495
00:28:07,886 --> 00:28:13,223
And as they spin, they generate flashing beams of energy.
496
00:28:13,225 --> 00:28:15,625
This beam is like a lighthouse beam.
497
00:28:15,627 --> 00:28:18,962
You see these periodic flashes many times per second.
498
00:28:18,964 --> 00:28:20,563
So, every time you see it ...
499
00:28:20,565 --> 00:28:23,834
beam, beam, beam.
500
00:28:23,836 --> 00:28:26,903
These beams are the pulsar's calling card.
501
00:28:26,905 --> 00:28:29,639
They're generated by the elemental chaos
502
00:28:29,641 --> 00:28:32,241
raging inside a neutron star.
503
00:28:32,243 --> 00:28:34,110
Although the star is predominantly
504
00:28:34,112 --> 00:28:35,978
a ball of neutrons,
505
00:28:35,980 --> 00:28:39,716
the crust is sprinkled with protons and electrons,
506
00:28:39,718 --> 00:28:41,918
spinning hundreds of times a second,
507
00:28:41,920 --> 00:28:44,621
generating an incredible magnetic field.
508
00:28:46,391 --> 00:28:48,191
And with this strong magnetic field,
509
00:28:48,193 --> 00:28:50,260
you can create strong electric fields.
510
00:28:50,262 --> 00:28:51,994
And the electric and magnetic fields
511
00:28:51,996 --> 00:28:55,665
can work off of each other and become radiation.
512
00:28:55,667 --> 00:29:01,337
These neutron stars send jets ... beams of radiation ...
513
00:29:01,339 --> 00:29:03,406
out of their spinning poles.
514
00:29:03,408 --> 00:29:05,942
And if their spinning pole is misaligned,
515
00:29:05,944 --> 00:29:07,545
if they're a little bit tilted,
516
00:29:07,547 --> 00:29:11,815
this beam will make circles, across the universe.
517
00:29:11,817 --> 00:29:14,550
And if we're in the path of one of these circles,
518
00:29:14,552 --> 00:29:17,086
we'll see a flash...
519
00:29:17,088 --> 00:29:18,287
A flash.
520
00:29:18,289 --> 00:29:19,889
Just like if you're on a ship,
521
00:29:19,891 --> 00:29:22,559
and you observe a distant lighthouse in a foggy night,
522
00:29:22,561 --> 00:29:26,630
you can see pulsars across the vast expanse of space
523
00:29:26,632 --> 00:29:30,166
because they are immensely powerful beams of light.
524
00:29:30,168 --> 00:29:33,570
But sometimes, pulsars get an extra push
525
00:29:33,572 --> 00:29:37,240
that accelerates the spin even more.
526
00:29:37,242 --> 00:29:39,376
The way you make it spin even faster
527
00:29:39,378 --> 00:29:42,578
is by subsequently dumping more material onto it.
528
00:29:42,580 --> 00:29:45,114
That's called "accretion," and you end up spinning it up
529
00:29:45,116 --> 00:29:47,183
even faster than it was already spinning.
530
00:29:47,185 --> 00:29:49,252
Like stellar vampires,
531
00:29:49,254 --> 00:29:51,589
pulsars are ready to suck the life
532
00:29:51,591 --> 00:29:54,958
out of any objects that stray too close.
533
00:29:54,960 --> 00:29:57,393
Gravity is bringing that material in,
534
00:29:57,395 --> 00:30:00,129
which means that any spin it has is accelerated.
535
00:30:00,131 --> 00:30:01,998
It spins faster and faster.
536
00:30:02,000 --> 00:30:04,200
These millisecond pulsars
537
00:30:04,202 --> 00:30:08,471
spin at around 700 revolutions per second.
538
00:30:08,473 --> 00:30:10,541
They are the ultimate kitchen blender ...
539
00:30:10,543 --> 00:30:14,844
they will chop, they will slice, they will even julienne fry.
540
00:30:17,549 --> 00:30:19,616
So, what stops neutron stars
541
00:30:19,618 --> 00:30:22,752
from simply tearing themselves apart?
542
00:30:22,754 --> 00:30:26,156
Neutron stars are incredibly exotic objects
543
00:30:26,158 --> 00:30:30,093
with immense, immense forces that bind them together,
544
00:30:30,095 --> 00:30:32,361
and so, they can be held rigid even against
545
00:30:32,363 --> 00:30:34,631
these incredibly fast rotation speeds.
546
00:30:38,369 --> 00:30:40,236
Bullock: They have incredibly strong gravity,
547
00:30:40,238 --> 00:30:42,172
and this is what allows them to hold together
548
00:30:42,174 --> 00:30:44,241
even though they're spinning around so fast.
549
00:30:47,312 --> 00:30:52,715
The speed of the spin is hard to imagine.
550
00:30:52,717 --> 00:30:54,917
On earth, a day is 24 hours long.
551
00:30:54,919 --> 00:30:59,922
On a neutron star, it's a 700th of a second long.
552
00:30:59,924 --> 00:31:01,591
Super-speeding pulsars
553
00:31:01,593 --> 00:31:03,859
are not the only weird stars
554
00:31:03,861 --> 00:31:06,395
that scientists are coming to grips with.
555
00:31:06,397 --> 00:31:08,798
There is one other type of neutron star,
556
00:31:08,800 --> 00:31:12,735
that has the most powerful magnetic field in the universe.
557
00:31:12,737 --> 00:31:17,040
This magnetic monster is called a "magnetar."
558
00:31:32,490 --> 00:31:35,692
Astronomers monitoring pulsing neutron stars
559
00:31:35,694 --> 00:31:38,561
have noticed something very odd.
560
00:31:38,563 --> 00:31:44,233
On very rare occasions, they can suddenly speed up.
561
00:31:44,235 --> 00:31:45,435
That's amazing.
562
00:31:45,437 --> 00:31:47,437
I mean, you've got this incredibly dense object,
563
00:31:47,439 --> 00:31:48,839
and suddenly, it's spinning faster.
564
00:31:48,841 --> 00:31:50,973
It happens...Instantly.
565
00:31:50,975 --> 00:31:52,775
They'll suddenly change frequency.
566
00:31:52,777 --> 00:31:56,112
It would take an amazing amount of power to do that.
567
00:31:56,114 --> 00:31:57,714
What's doing it?
568
00:31:57,716 --> 00:32:02,318
These sudden changes in speed are called "glitches."
569
00:32:02,320 --> 00:32:04,654
One leading idea for what causes these glitches
570
00:32:04,656 --> 00:32:07,257
is that the core material latches onto the crust,
571
00:32:07,259 --> 00:32:10,460
and this affects the way it can spin around.
572
00:32:10,462 --> 00:32:14,397
Excess material beneath the crust cracks it open,
573
00:32:14,399 --> 00:32:16,399
causing the glitch.
574
00:32:16,401 --> 00:32:20,336
This process releases a tremendous amount of radiation,
575
00:32:20,338 --> 00:32:24,874
a blast of x-rays, causes the face of the neutron star
576
00:32:24,876 --> 00:32:29,212
to rearrange itself, and for the rotation speed to change.
577
00:32:29,214 --> 00:32:31,881
But there's another possible explanation.
578
00:32:31,883 --> 00:32:36,152
Glitches could also be caused by starquakes.
579
00:32:36,154 --> 00:32:38,688
Sometimes, the crust gets ruptured.
580
00:32:38,690 --> 00:32:42,825
Anything that basically changes the geometry of the pulsar
581
00:32:42,827 --> 00:32:45,695
can change the rate at which it spins.
582
00:32:45,697 --> 00:32:47,230
So, what could be powerful enough
583
00:32:47,232 --> 00:32:50,633
to cause these starquakes?
584
00:32:50,635 --> 00:32:51,634
It's hard to believe
585
00:32:51,636 --> 00:32:54,037
that there's any force in the universe
586
00:32:54,039 --> 00:32:57,106
that could deform the matter inside of a neutron star,
587
00:32:57,108 --> 00:32:59,842
which is undergoing tremendous gravity.
588
00:32:59,844 --> 00:33:01,444
But when it comes to a neutron star,
589
00:33:01,446 --> 00:33:04,647
if there's one thing that can do it, it's magnetism.
590
00:33:04,649 --> 00:33:06,382
Extreme magnetic fields
591
00:33:06,384 --> 00:33:09,185
within the star can get so twisted
592
00:33:09,187 --> 00:33:11,921
they can rip the crust wide open.
593
00:33:11,923 --> 00:33:14,591
And so, the surface can restructure itself,
594
00:33:14,593 --> 00:33:16,125
and constantly reshape.
595
00:33:16,127 --> 00:33:18,794
And just a tiny reconfiguration
596
00:33:18,796 --> 00:33:20,564
of the surface of a neutron star,
597
00:33:20,566 --> 00:33:22,198
on the order of a few millimeters,
598
00:33:22,200 --> 00:33:26,736
would be associated with an enormous release of energy.
599
00:33:26,738 --> 00:33:28,805
The neutron star's immense gravity
600
00:33:28,807 --> 00:33:34,009
smooths over the star's surface almost instantaneously.
601
00:33:34,011 --> 00:33:36,480
It's like the glitch never happened.
602
00:33:40,017 --> 00:33:42,084
When it comes to neutron stars,
603
00:33:42,086 --> 00:33:46,756
there is no end to magnetic mayhem.
604
00:33:46,758 --> 00:33:48,691
Meet the reigning champion
605
00:33:48,693 --> 00:33:53,228
in the universal "strongest magnetic field" competition ...
606
00:33:53,230 --> 00:33:55,764
the magnetar.
607
00:33:55,766 --> 00:33:59,302
1 in 10 neutron stars formed during a supernova
608
00:33:59,304 --> 00:34:01,771
becomes a magnetar.
609
00:34:01,773 --> 00:34:06,376
The thing about magnetars, as is implied in their name ...
610
00:34:06,378 --> 00:34:08,578
the magnetic field on them is so strong,
611
00:34:08,580 --> 00:34:11,114
that even somebody who is used to using big numbers ...
612
00:34:11,116 --> 00:34:12,915
like, say, an astronomer ...
613
00:34:12,917 --> 00:34:15,985
is still kind of in awe of these things.
614
00:34:15,987 --> 00:34:18,321
Magnetars have a magnetic field
615
00:34:18,323 --> 00:34:22,525
one thousand trillion times stronger than that of earth's.
616
00:34:22,527 --> 00:34:24,460
This amount of magnetism
617
00:34:24,462 --> 00:34:29,332
will seriously mess up anything that comes close.
618
00:34:29,334 --> 00:34:31,800
Bullock: Any normal object that we are familiar with,
619
00:34:31,802 --> 00:34:35,471
if it got close to a magnetar, it would just be shredded.
620
00:34:35,473 --> 00:34:37,674
Any charged particle with any movement at all,
621
00:34:37,676 --> 00:34:39,609
would just be torn from its atom.
622
00:34:39,611 --> 00:34:42,945
It would be just an insane situation.
623
00:34:42,947 --> 00:34:47,350
Magnetars burn brightly, but their lives are brief.
624
00:34:47,352 --> 00:34:48,685
We think magnetars ...
625
00:34:48,687 --> 00:34:51,287
these intensely magnetized neutron stars ...
626
00:34:51,289 --> 00:34:53,156
can only be really short-lived.
627
00:34:53,158 --> 00:34:55,425
Their magnetic field is so powerful
628
00:34:55,427 --> 00:34:57,961
that it should decay over very rapid time scales,
629
00:34:57,963 --> 00:35:00,630
only on the order of a few ten thousand years.
630
00:35:00,632 --> 00:35:04,967
It seems their very strength leads to their downfall.
631
00:35:04,969 --> 00:35:06,970
That magnetic field is so strong
632
00:35:06,972 --> 00:35:09,972
that it's picking up material around it, and accelerating it.
633
00:35:09,974 --> 00:35:12,041
Well, that acts like a drag, slowing it down.
634
00:35:12,043 --> 00:35:15,177
So, over time, the spin of the neutron star slows,
635
00:35:15,179 --> 00:35:16,946
and the magnetic field dies away.
636
00:35:19,250 --> 00:35:20,583
During their lives,
637
00:35:20,585 --> 00:35:24,186
magnetars operate very differently than pulsars.
638
00:35:24,188 --> 00:35:25,854
They don't have beams.
639
00:35:25,856 --> 00:35:28,858
Their magnetic fields shoot out gigantic bursts
640
00:35:28,860 --> 00:35:32,261
of high-intensity radiation.
641
00:35:32,263 --> 00:35:35,932
But recently, astronomers have spotted one neutron star
642
00:35:35,934 --> 00:35:38,468
that's hard to classify.
643
00:35:38,470 --> 00:35:42,639
It behaves like a stellar Jekyll and Hyde.
644
00:35:44,743 --> 00:35:48,544
So, this particular neutron star is a really weird example.
645
00:35:48,546 --> 00:35:51,013
It behaves both like a radio pulsar,
646
00:35:51,015 --> 00:35:53,950
and also a highly-magnetized magnetar.
647
00:35:53,952 --> 00:35:56,219
It has the extreme magnetic fields,
648
00:35:56,221 --> 00:35:59,021
it can have these magnetic outbursts,
649
00:35:59,023 --> 00:36:01,691
but it also has this strong jet of radiation
650
00:36:01,693 --> 00:36:02,892
coming out of its poles.
651
00:36:02,894 --> 00:36:07,029
It's almost like it has a split personality.
652
00:36:07,031 --> 00:36:09,298
When first sighted in 2000,
653
00:36:09,300 --> 00:36:11,767
this star was emitting radio waves ...
654
00:36:11,769 --> 00:36:14,703
typical pulsar behavior.
655
00:36:14,705 --> 00:36:18,707
Then, 16 years later, it stopped pulsing,
656
00:36:18,709 --> 00:36:23,179
and suddenly started sending out massive X-ray bursts ...
657
00:36:23,181 --> 00:36:26,115
the actions of a magnetar.
658
00:36:26,117 --> 00:36:29,118
Scientists were baffled.
659
00:36:29,120 --> 00:36:32,321
We don't know if this thing is a pulsar turning into a magnetar,
660
00:36:32,323 --> 00:36:34,924
or a magnetar turning into a pulsar.
661
00:36:34,926 --> 00:36:37,860
One theory is that these X-ray bursts happened
662
00:36:37,862 --> 00:36:41,930
because the star's magnetic field suddenly twisted.
663
00:36:41,932 --> 00:36:46,402
The stress became so great, the star cracked wide open,
664
00:36:46,404 --> 00:36:50,406
releasing the x-rays from the fractured crust.
665
00:36:50,408 --> 00:36:52,675
A neutron star is the densest material
666
00:36:52,677 --> 00:36:54,543
that we know of in the universe.
667
00:36:54,545 --> 00:36:55,811
And yet, we've seen things
668
00:36:55,813 --> 00:36:58,281
that actually make it shift and pull apart.
669
00:36:58,283 --> 00:37:00,883
This neutron star is actually ripping itself apart
670
00:37:00,885 --> 00:37:02,885
under the forces of the magnetic field.
671
00:37:02,887 --> 00:37:04,420
If this is the case,
672
00:37:04,422 --> 00:37:08,891
placid neutron stars turn into raging magnetars,
673
00:37:08,893 --> 00:37:12,428
growing old disgracefully.
674
00:37:12,430 --> 00:37:14,364
When you think about the life cycle of a human being,
675
00:37:14,366 --> 00:37:16,299
we seem to kind of slow down over age,
676
00:37:16,301 --> 00:37:17,767
become a little more calmer.
677
00:37:17,769 --> 00:37:19,368
Neutron stars do the opposite.
678
00:37:19,370 --> 00:37:21,237
They can be spinning faster than they were
679
00:37:21,239 --> 00:37:22,504
when they were formed,
680
00:37:22,506 --> 00:37:24,774
and the magnetic field can get stronger over time.
681
00:37:24,776 --> 00:37:28,045
It's sort of a reverse aging process.
682
00:37:28,047 --> 00:37:31,248
But these strange changes are extremely rare.
683
00:37:31,250 --> 00:37:36,319
Most pulsars are as regular as clockwork.
684
00:37:36,321 --> 00:37:38,254
Pulsars are normally incredibly regular.
685
00:37:38,256 --> 00:37:41,524
You can literally set your watch to the timing of their pulse.
686
00:37:41,526 --> 00:37:43,993
And it's this stability that we may use
687
00:37:43,995 --> 00:37:47,797
in our future exploration of the universe.
688
00:37:47,799 --> 00:37:49,598
You know, if you're a starship Captain,
689
00:37:49,600 --> 00:37:52,735
what you need is a galactic GPS system.
690
00:37:52,737 --> 00:37:55,838
Well it turns out, neutron stars may be the answer.
691
00:38:11,189 --> 00:38:12,989
Astronomers often compare
692
00:38:12,991 --> 00:38:17,260
the steady flash of spinning neutron stars, called "pulsars,"
693
00:38:17,262 --> 00:38:19,394
to cosmic lighthouses.
694
00:38:19,396 --> 00:38:23,132
These flashes are not only remarkably reliable,
695
00:38:23,134 --> 00:38:28,737
each pulsar has its very own distinct flickering beam.
696
00:38:28,739 --> 00:38:31,208
Each one has a slightly different frequency.
697
00:38:31,210 --> 00:38:33,943
Each one has a slightly different rate.
698
00:38:33,945 --> 00:38:37,346
Anyone in the galaxy, no matter where you are,
699
00:38:37,348 --> 00:38:43,553
can all agree on the positions of these pulsars.
700
00:38:43,555 --> 00:38:45,954
The unique signature of pulsars
701
00:38:45,956 --> 00:38:48,557
opens up intriguing possibilities
702
00:38:48,559 --> 00:38:50,160
for the future of space travel.
703
00:38:55,633 --> 00:38:58,033
straughn: We would basically be using pulsars
704
00:38:58,035 --> 00:39:01,036
to be able to sort of triangulate where we're at.
705
00:39:01,038 --> 00:39:03,239
And because those pulses are so precise,
706
00:39:03,241 --> 00:39:06,442
we can use that in a similar way that we use GPS satellites
707
00:39:06,444 --> 00:39:07,944
that are stationed above the earth.
708
00:39:10,982 --> 00:39:13,782
Using pulsars as navigational aids
709
00:39:13,784 --> 00:39:15,585
is not a new idea.
710
00:39:15,587 --> 00:39:18,988
It was recognized by the NASA voyager mission
711
00:39:18,990 --> 00:39:22,058
in the 1970's.
712
00:39:22,060 --> 00:39:24,393
Affixed to the surface of those spacecraft
713
00:39:24,395 --> 00:39:25,595
is a golden record.
714
00:39:25,597 --> 00:39:27,729
And on the plate that covers that record
715
00:39:27,731 --> 00:39:31,067
is a pulsar map, which in principle could tell
716
00:39:31,069 --> 00:39:34,536
an advanced alien civilization how to find earth,
717
00:39:34,538 --> 00:39:37,006
because it uses the position of earth
718
00:39:37,008 --> 00:39:39,207
relative to 14 known pulsars,
719
00:39:39,209 --> 00:39:41,410
as, effectively, a way to triangulate
720
00:39:41,412 --> 00:39:42,878
the position of our planet
721
00:39:42,880 --> 00:39:45,815
relative to all of these pulsars.
722
00:39:45,817 --> 00:39:51,820
Aliens haven't made contact, but NASA still uses pulsar maps.
723
00:39:51,822 --> 00:39:53,755
NASA recently launched a satellite
724
00:39:53,757 --> 00:39:55,424
called "nicer sextant"
725
00:39:55,426 --> 00:39:57,961
that exists on the international space station,
726
00:39:57,963 --> 00:40:00,763
that is being used to test these types of theories.
727
00:40:09,506 --> 00:40:11,908
they've used pulsars to figure out the location
728
00:40:11,910 --> 00:40:13,910
of an object orbiting around the earth
729
00:40:13,912 --> 00:40:16,246
at 17,000 miles an hour,
730
00:40:16,248 --> 00:40:18,047
and they were able to pinpoint its location
731
00:40:18,049 --> 00:40:19,581
to within three miles.
732
00:40:19,583 --> 00:40:21,717
That's pretty incredible.
733
00:40:21,719 --> 00:40:26,054
By recognizing their position relative to known pulsars,
734
00:40:26,056 --> 00:40:29,725
future space missions could navigate the universe.
735
00:40:36,333 --> 00:40:39,335
neutron stars are gonna take us on this incredible journey ...
736
00:40:39,337 --> 00:40:40,736
something as necessary
737
00:40:40,738 --> 00:40:42,604
as knowing where you are in the galaxy.
738
00:40:42,606 --> 00:40:44,540
We could be many hundreds of light years away,
739
00:40:44,542 --> 00:40:46,275
but neutron stars can actually show us
740
00:40:46,277 --> 00:40:47,810
where in the milky way we are.
741
00:40:55,686 --> 00:40:56,952
I read a lot of science fiction,
742
00:40:56,954 --> 00:40:59,688
and I love the idea of being able to go
743
00:40:59,690 --> 00:41:02,158
from star to star, planet to planet.
744
00:41:02,160 --> 00:41:05,828
It's kind of weird to think that, in the future,
745
00:41:05,830 --> 00:41:08,364
as a galactic coordinate grid,
746
00:41:08,366 --> 00:41:12,701
we might wind up using these gigantic atomic nuclei,
747
00:41:12,703 --> 00:41:15,739
these rapidly spinning, bizarrely-constructed,
748
00:41:15,741 --> 00:41:20,176
magnetic, fiercely gravitational objects like neutron stars.
749
00:41:23,381 --> 00:41:26,115
Neutron stars have come a long way
750
00:41:26,117 --> 00:41:30,853
since being mistaken for little green men.
751
00:41:30,855 --> 00:41:35,391
Once overlooked as astronomical oddities,
752
00:41:35,393 --> 00:41:42,866
they've now taken center stage as genuine stellar superstars.
753
00:41:42,868 --> 00:41:45,333
What's really exciting about neutron stars is that,
754
00:41:45,335 --> 00:41:47,670
we're at the beginning of studying them.
755
00:41:47,672 --> 00:41:49,938
We're not at the conclusion. We've learned a lot,
756
00:41:49,940 --> 00:41:51,741
but there's a lot more to be learned.
757
00:41:51,743 --> 00:41:56,412
Sutter: From the humble neutron comes the most powerful,
758
00:41:56,414 --> 00:41:59,949
the most rapid, the strongest magnetic field,
759
00:41:59,951 --> 00:42:03,619
the most exotic objects in the cosmos.
760
00:42:03,621 --> 00:42:05,421
I love the idea of a Phoenix,
761
00:42:05,423 --> 00:42:07,957
something actually rising from its own ashes.
762
00:42:07,959 --> 00:42:10,426
You think something dies, and that's the end of the story,
763
00:42:10,428 --> 00:42:12,094
but something even more beautiful,
764
00:42:12,096 --> 00:42:14,563
even more fascinating, comes afterwards.
765
00:42:14,565 --> 00:42:16,699
I told you at the beginning, and you didn't believe me,
766
00:42:16,701 --> 00:42:18,100
but now, I hope you do ...
767
00:42:18,102 --> 00:42:20,769
neutron stars are the most fascinating
768
00:42:20,771 --> 00:42:23,305
astrophysical objects in the universe.
61223
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