Placeholder Image

字幕列表 影片播放

  • so in an astronomical beauty contest, they might not be as popular as black holes, but it doesn't make them any less enigmatic and extreme.

  • I'm talking about neutron stars.

  • Little is known about these super dense remains of ancient stars, but one recent event may shed light on at least some of their mysteries.

  • Good old regular stars keep their spherical shape because they're gigantic.

  • Mass creates a powerful gravitational field that pulls gas toward the center.

  • Well, that's happening.

  • Their cores produce enough energy to prevent gas from gathering too close to the center.

  • But once a star becomes too old and massive about 4 to 8 times bigger than our sun, it doesn't have any more fuel left.

  • That's why all the reactions in its core stop the star's outer layers instantly try to collapse inward, but they bounce off the core, which remains incredibly dense.

  • That's when everything but the star's core explodes in a fiery supernova.

  • But that's not the end of the star.

  • Even without the outer layers, its core keeps collapsing.

  • At one moment, the pressure inside become so high that electrons and protons virtually melt into each other, resulting in a mass that consists of 90% neutrons.

  • It means that the thing just can't be squashed any tighter.

  • It be like stuffing all 2700 feet of the Burj Khalifa into an aspirin.

  • Then energy starts to leave the fading object, finishing off the transformation into a neutron star.

  • The amount of this energy is so great that it can be compared with the combined light emitted by all the stars in the observable universe.

  • Energy is leaving the star in the form of neutrinos particles that are created when positively charged protons turn into neutrons during a supernova explosion.

  • The star emits almost 10 times more neutrinos than the number of protons, electrons and neutrons in the sun.

  • No wonder such conditions give birth to something truly scary.

  • A neutron star, which is basically a giant nucleus.

  • The central part of an atom is relatively small, even though scientists don't know for sure how big neutron stars are.

  • They suppose that thes space bodies shouldn't be bigger than 20 miles across roughly the size of Manhattan.

  • But even with such a modest size for a celestial body, any neutron star will be at least two and 1/2 times heavier than the sun and mind you, our son is nearly 865,000 miles in diameter, which is 109.

  • Earth's put side to side.

  • Think of it like this.

  • If you scoop just a teaspoon of a neutron, stars insides.

  • This stuff would wait no less than a 1,000,000,000 times.

  • That's very dense, so dense that the next step is a black hole itself and nearly as dances.

  • I was in middle school now about that event I mentioned earlier.

  • Scientists have recently observed a collision of two neutron stars.

  • They were able to see this phenomenon thanks to the gravitational waves.

  • That crash created two small neutron stars, collided with immense force and merged into one larger star.

  • The thing collapsed almost immediately after being born, but not before it provided astronomers with several much needed answers like their consistency.

  • As you can probably understand, it's impossible to create anything like a neutron star on our planet.

  • That's why astronomers could only make guesses about these things composition.

  • There were two main theories.

  • Some scientists claim that neutron stars were soft and pliable, while others were sure that they were extremely hard and could withstand immense pressure.

  • If neutron stars were soft, it would take them almost no time to collapse.

  • But the picture astronomers saw in a short period of time between the collision and the collapse was different.

  • The new star was spinning so fast that the speed of its rotation was holding it together as why the poor thing manage to exist for a few milliseconds before it turned into a gaping black hole.

  • It was all the evidence supporters of the hard neutron star theory needed.

  • They even not only gave scientists a better idea of the neutron stars makeup.

  • It also help them figure out its size.

  • The star had to be about 13 miles across with a mass about 60% bigger than that of our sun.

  • The thing is, larger neutron stars can survive longer before collapsing with especially huge stars.

  • Process can take hours or maybe even days.

  • But the star I just told you about cease to exist in a fraction of a second, which made astronomers conclude that it was a baby size neutron star.

  • However unfortunate the crash was for the two stars that collided that day, it shed some more light on the mysterious nature of neutron stars.

  • And even though scientists kept searching the skies for more information about these extreme objects, today we know much more about them than we did a few years ago.

  • Which makes me wonder if scientists could find the answers toe on Lee.

  • One space mystery.

  • What would you want to be?

  • Black holes?

  • Dark matter.

  • The origin of our universe?

  • Let me know down to the comments.

  • But you know, one of the coolest things about neutron stars.

  • If there was life on one of them, it be two dimensional.

  • Like a comic book.

  • Their gravity is powerful enough to literally flatten anything on their surface.

  • And if they had an atmosphere, it wouldn't stretch up any further than a foot or so above the surface of the star.

  • A neutron stars magnetic field can be hundreds of billions of times stronger than what we have on Earth.

  • I told you, these guys are extreme.

  • Neutron stars also rotate, and they do it so fast your head would spin just a cz much the fastest spinning neutron star scientists know off makes more than 700 turns per second, and here our entire planet takes a full 24 hours to complete just one rotation.

  • Another extreme feature of neutron stars is their temperature surface can get heated upto a toasty 107,000 degrees Fahrenheit.

  • Um, s'mores.

  • Anyone for comparison The temperature on the surface of our son rarely rises above 10,000 degrees.

  • In other words, a tiny neutron star can be 10 times hotter than our massive son.

  • The fact that astronomers don't know much about neutron stars doesn't mean these space objects are hard to come by.

  • Throughout the history of our Milky Way galaxy, there might have existed around 100 million of them.

  • But astronomers have problems locating neutron stars because most of them are cold and rotate very slowly, which makes them almost undetectable.

  • At the same time, the famous Hubble Space Telescope managed to find several that were emitting thermal radiation.

  • Now I've already mentioned that neutron stars have incredibly powerful gravitational fields.

  • This is why the light coming from one often doesn't manage to escape and get stuck in an orbit around the star.

  • And in this case, you can see the entire star surfaced on Lee when you observe it from one particular point.

  • Now imagine putting a sponge in a small puddle of water.

  • The water will fill the Hollows in the sponge and disappear in no time.

  • Neutron stars work sort of the same way.

  • As soon as they get hold of some stray matter, they immediately suck it up like a sponge, and this can increase the speed of their rotation by up to 100 spins a second.

  • When neutron stars begin to rotate even faster than usual, they take on a more oval shape.

  • But once a star gets older and slows down, it returns to its original spirit.

  • KAL form.

  • Neutron stars aren't always lonely wanderers.

  • Astronomers know off at least two that have planets orbiting around them.

  • The origin of these satellites isn't clear.

  • They might have been with the stars from the very beginning and survived their transformation into neutron stars.

  • Or they could have been captured by the enormous gravitational pull of the super dense space objects draw augur Ah, planet orbiting one of the neutron stars is the tiniest exo planet astronomers have located.

  • So far, its mass is only two times bigger than our own moon.

  • Hey, if you learn something new today.

  • Then give the video a line, can share it with a friend and here some other videos I think you'll enjoy.

  • Just click to the left or right, and remember, stay on the bright side of life.

so in an astronomical beauty contest, they might not be as popular as black holes, but it doesn't make them any less enigmatic and extreme.

字幕與單字

單字即點即查 點擊單字可以查詢單字解釋

B1 中級

是什麼讓中子星成為宇宙中最極端的東西? (What Makes Neutron Stars the Most Extreme Things in the Universe)

  • 1 0
    林宜悉 發佈於 2021 年 01 月 14 日
影片單字