yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Atoms As Big As Mountains — Neutron Stars Explained


3m read
·Nov 2, 2024

Neutron stars are one of the most extreme things in the universe. They’re like giant atom cores. Kilometers in diameter, unbelievably dense and violent. But how can something like this even exist?

The life of a star is dominated by two forces being in balance: its own gravity and the radiation pressure of its fusion reaction. In the core of stars, hydrogen is fused into helium. Eventually, the hydrogen in the core is exhausted. If the star is massive enough, helium is now fused into carbon.

The cores of these massive stars become layered like onions, as heavier and heavier atomic nuclei build up at the center. Carbon is fused into neon, which leads to oxygen, which leads to silicon. Eventually, the fusion reaction hits iron, which cannot fuse into another element. When the fusion stops, the radiation pressure drops rapidly.

The star is no longer in balance, and if its core mass exceeds about 1.4 solar masses, a catastrophic collapse takes place. The outer part of the core reaches velocities of up to 70,000 km/s, as it collapses towards the center of the star. Now, only the fundamental forces inside an atom are left to fight the gravitational collapse.

The quantum-mechanical repulsion of electrons is overcome, and electrons and protons fuse into neutrons packed as densely as an atomic nucleus. The outer layers of the star are catapulted into space in a violent supernova explosion. So, now we have a neutron star!

Its mass is between 1 and 3 Suns, but compressed to an object about 25 kilometers wide! And 500,000 times the mass of Earth, in this tiny ball that’s roughly the diameter of Manhattan. It’s so dense that one cubic centimeter of neutron star contains the same mass as an iron cube 700 meters across.

That’s roughly 1 billion tons, as massive as Mount Everest, in a space the size of a sugar cube. Neutron star gravity is pretty impressive too! If you were to drop an object from 1 meter over the surface, it would hit the star in one microsecond and accelerate up to 7.2 million km/h.

The surface is superflat, with irregularities of 5 millimeters maximum, with a superthin atmosphere of hot plasma. The surface temperature is about 1 million kelvin, compared to 5,800 kelvin for our Sun.

Let’s look inside the neutron star! The crust is extremely hard and is most likely made of an iron atom nuclei lattice with a sea of electrons flowing through them. The closer we get to the core, the more neutrons and the fewer protons we see until there’s just an incredibly dense soup of indistinguishable neutrons.

The cores of neutron stars are very, very weird. We are not sure what their properties are, but our closest guess is superfluid neutron degenerate matter or some kind of ultradense quark matter called quark-gluon plasma. That does not make any sense in the traditional way and can only exist in such an ultraextreme environment.

In many ways, a neutron star is similar to a giant atom core. The most important difference is that atom cores are held together by strong interaction and neutron stars by gravity. As if all this wasn’t extreme enough, let’s take a look at a few other properties.

Neutron stars spin very, very fast, young ones several times per second. And if there’s a poor star nearby to feed the neutron star, it can rotate up to several hundred times per second. Like the object PSRJ1748-2446ad. It spins at approximately 252 million km/h.

This is so fast that the star has a rather strange shape. We call these objects pulsars because they emit a strong radio signal. And the magnetic field of a neutron star is roughly 8 trillion times stronger than the magnetic field of Earth. So strong that atoms get bent when they enter its influence.

Okay, I think we got the point across. Neutron stars are some of the most extreme, but also some of the coolest objects in the universe. Hopefully, we will one day send spaceships to learn more about them and take some neat pictures! But we shouldn’t get too close!

Subtitles by the Amara.org community

More Articles

View All
Desert Monster Tries to Survive in the American Southwest | National Geographic
The Gila monster is the most charismatic reptile we have in Arizona, for sure. We have seen temperatures increasing in the Tucson area. Gila monsters, you know, depend on humidity, and if humidity goes down lower earlier in the season, that could affect t…
Curvature formula, part 2
In the last video, I started to talk about the formula for curvature. Just to remind everyone of where we are, you imagine that you have some kind of curve in, let’s say, two-dimensional space, just for the sake of being simple. Let’s say this curve is pa…
The Dark Side of Everyday Things | Why We Can't Have Nice Things Anymore
to participate in viral challenges popularized by the platform. These incidents underline a disturbing trend: social media platforms, particularly TikTok, have the potential to influence vulnerable users, especially children, into engaging in dangerous b…
Watch: Nearly 10,000 People Ice Fish for Charity | National Geographic
This is the world’s largest party on ice. We are the largest charitable fishing contest in the entire world. We have upwards of 10,000 people out here, and we’re all supporting local charities. The entire thing is volunteer-run. We have approximately 80 v…
Who God is in Different Cultures | The Story of God
Who God is, is almost universally a great unknown. There are different manifestations of God: different statues, different icons, different sounds, smells, looks of God across cultures. God has a sound. To Navajo, God is a light, bright light to many peop…
15 Ways to Get Mentally Stronger
Did you know that mentally tougher athletes consistently outperform their mentally weaker counterparts? A recent study has shown that roughly 80 percent of mentally tough athletes tend to achieve more or perform better. Now, it goes without saying that be…