The video provides a detailed explanation of the life cycle of a neutron star, starting from the formation of a star through a supernova explosion to its final state as a neutron star.
Stars exist due to a delicate balance of gravity and nuclear fusion. When the hydrogen in a star is exhausted, it undergoes a supernova explosion, which results in the formation of a neutron star. This process involves the fusion of heavier elements, such as carbon, neon, oxygen, and silicon, into iron. The core of the star is then crushed by the enormous weight of the star above it, leading to the formation of a neutron star.
Neutron stars are extremely dense, with a mass around a million times that of the Earth but compressed to an object about 25 kilometers wide. They have the strongest gravity outside black holes, and their surfaces reach 1,000,000 degrees Celsius. The outermost layers of a neutron star are made of iron left over from the supernova, squeezed together in a crystal lattice, with a sea of electrons flowing through them.
When neutron stars first collapse, they begin to spin very fast, creating pulses because their magnetic field creates a beam of radio waves. These radio pulsars are the best-known type of neutron star, with about 2,000 known in the Milky Way. These magnetic fields are the strongest in the universe.
Neutron stars can also interact with other neutron stars, leading to a kilonova explosion that spews out a lot of their guts. When they do, the conditions become so extreme that heavy nuclei are made again. This is probably the origin of most of the heavy elements in the universe, like gold, uranium, and platinum.
The video concludes by emphasizing the importance of understanding the life cycle of neutron stars, as they are the origin of most of the heavy elements in the universe. The video also includes a call to action for viewers to support the channel by purchasing items from their shop.
1. Neutron stars are one of the most extreme and violent things in the universe.
2. They are giant atomic nuclei, only a few kilometers in diameter, but as massive as stars.
3. Neutron stars owe their existence to the death of something majestic, specifically a star.
4. Stars exist because of a fragile balance, where the mass of hot plasma is being pulled inwards by gravity.
5. This balance allows stars to be stable until the hydrogen is exhausted.
6. Medium stars, like our Sun, go through a giant phase, where they burn helium into carbon and oxygen, before they eventually turn into white dwarfs.
7. In stars many times the mass of our Sun, things get interesting when the helium is exhausted.
8. For a moment, the balance of pressure and radiation tips, and gravity wins, squeezing the star tighter than before.
9. The core burns hotter and faster, while the outer layers of the star swell by hundreds of times, fusing heavier and heavier elements.
10. Carbon burns to neon in centuries, neon to oxygen in a year, oxygen to silicon in months, and silicon to iron in a day.
11. After this, the fusion suddenly stops, and the balance ends.
12. Without the outward pressure from fusion, the core is crushed by the enormous weight of the star above it.
13. This implosion bounces off the iron core, producing a shock wave that explodes outwards and catapults the rest of the star into space.
14. This is what we call a supernova explosion, and it will outshine entire galaxies.
15. What remains of the star is now a neutron star.
16. Its mass is around a million times the mass of the Earth but compressed to an object about 25 kilometers wide.
17. It’s so dense that the mass of all living humans would fit into one cubic centimeter of neutron star matter.
18. From the outside, a neutron star is unbelievably extreme. Its gravity is the strongest, outside black holes.
19. Light is bent around it, meaning you can see the front and parts of the back.
20. Their surfaces reach 1,000,000 degrees Celsius, compared to a measly 6,000 degrees for our Sun.
21. Neutron stars are celestial ballerinas, spinning many times per second. This creates pulses because their magnetic field creates a beam of radio waves, which passes every time they spin.
22. These radio pulsars are the best-known type of neutron star. About 2,000 are known of in the Milky Way.
23. These magnetic fields are the strongest in the universe, a quadrillion times stronger than Earth’s after they’re born.
24. They’re called magnetars until they calm down a little.
25. The best kind of neutron stars are friends with other neutron stars. By radiating away energy as gravitational waves, ripples in spacetime, their orbits can decay, and they can crash into and kill each other in a kilonova explosion that spews out a lot of their guts.
26. When they do, the conditions become so extreme that, for a moment, heavy nuclei are made again. It’s not fusion putting nuclei together this time, but heavy neutron-rich matter falling apart and reassembling.
27. Only very recently, we’ve learned that this is probably the origin of most of the heavy elements in the universe, like gold, uranium, and platinum, and dozens more.
28. Not only do stars have to die to create elements, they have to die twice. Over millions of years, these atoms will mix back into the galaxy, but some of them end up in a cloud, which gravity pulls together to form stars and planets, repeating the cycle.
29. Our solar system is one example, and the remains of those neutron stars that came before us are all around us.
30. Our entire technological modern world was built out of the elements neutron stars made in eons past, sending these atoms on a thirteen-billion-year journey to come together and make us and our world.