Neutron stars are extremely dense remnants of dead stars approximately 4-8 times the mass of the Sun that have collapsed into a city-sized object composed almost entirely of neutrons. They form when a massive star runs out of fuel and collapses under its own gravity, compressing its core into neutrons. Neutron stars can spin hundreds of times per second and have immense gravitational pulls billions of times stronger than Earth. They emit radiation known as pulsars and have some of the strongest magnetic fields in the universe. Neutron stars can survive for billions of years as they slowly cool.

1. Neutron stars
How they work

2. Introduction
Neutron stars are the remains of dead stars approximately four to eight times the
mass of the sun. They are extremely dense objects about the size of a city,
compromising almost entirely of neutrons. These stars have an immense
gravitational pull and can spin hundreds of times every second.

3. Forming of neutron stars
A neutron star is born when a star is capable of producing a mass high enough to
overcome electron degeneracy pressure when it dies.
As the core collapses, temperatures rise higher and higher, eventually becoming
extreme enough to melt protons and electrons together, creating a large mass of
neutrons. The process continues until neutron degeneracy pressure finally
overcomes the increasing mass, and the remaining particles are thrown into space
in a supernova, leaving the neutron star behind.

4. Lifespan
Over time, the spinning speed of a neutron star steadily decreases. This is an
extremely slow process, occurring over thousands of years. Neutron stars cool
down through a number of complex processes, such as URCA and modified
URCA processes, photon cooling, and bremsstrahlung processes. These each
occur over different parts of the star’s life. Neutron stars can live longer than most
other stars in the universe.

5. Properties of a neutron star
Gravity
It’s huge, dense mass means a neutron star has a very strong gravitational pull
about 2,000,000,000,00 times stronger than earth. An object must accelerate up
to nearly half the speed of light to escape it’s pull.
Radiation
Neutron stars produce radiation known as pulsars, which are caused by particles
moving at close to the speed of light. Radiation is one of the primary ways
currently used to detect neutron stars from earth.

6. Properties of a neutron star
Magnetic field
A neutron star has one of the strongest magnetic fields out of most objects in the
universe. It is capable of causing unique particle interactions, such as the merging and
splitting of photons. It is millions of times stronger than magnetic fields on earth.
Structure
A neutron star is composed predominantly of neutrons, with different properties and
molecular structures deeper into the neutron star. Closer to the core, at extreme
pressure, quark-gluon plasmas and other unusual particles are able to form.

7. Properties of a neutron star
Density
Neutron stars have very high densities, with a single teaspoon worth of material roughly
equal to a billion tons. An average neutron star is about one and a half solar masses,
forced inside the space of a small city.
Temperature
The temperature of a neutron star begins extremely high, at about
10,000,000,000,000 degrees kelvin, cooling in a few seconds to
10,000,000,000,00, and then in a few years to 10,000,000 degrees kelvin. Over a
very, very long time, the temperature will eventually cool down.

8. Composition
A neutron star is predominantly composed of neutrons, with a few electrons and
protons within some of the layers of the star. A range of particles such as pion
condensates, delta isobars, and quark-gluon plasmas can be found within the
inner layers of the star where temperatures are high enough.
A neutron star emits neutrinos and other particles through pulsars, which can be
detected from earth. A neutron star can also have material orbiting it in the form of
stellar wind.

9. Examples
- PSR J0108-1431, aged 166 million years
- PSR B1257+12, aged 1-3 billion years
- PSR JO348+0432, aged 26,000,000,000 years
- PSR B1919+21, aged 16 million years

10. Discovery of neutron stars
- Walter Baade and Fritz Zwicky first proposed the existence of neutron stars,
in december 1933, at a meeting with physicists.
- 1965, Antony Hewish and Samuel Okoye found a strange source of radio
brightness in space.
- In 1967, Franco Pacini suggested the search for neutron stars should focus
on discovering the electromagnetic waves caused by the rapid spinning of the
star. Antony and Jocelyn Bell discovered the radio emissions of a pulsar from
a neutron star.
- In 1974, Joseph Taylor and Russell Hulse discovered the first two orbiting
neutron stars.

11. Appearance
A neutron star is completely black, but pulsars can be seen from earth. These
stars are approximately the size of cities. It would appear completely smooth and
circular, thanks to the extreme gravity of the star.

12. Some facts about neutron stars
- Gravity is so great that any material impacting with a neutron star will
essentially become part of the neutron star, it’s material becoming identical.
- A neutron star can spin at up to nearly a quarter of the speed of light.
- Neutron stars are one of the most long lasting objects in the universe.
- These stars can, and have been found to have, exoplanets orbiting around
them.
- Neutron stars no longer generate their own heat, but last up to billions of
years.

13. Conclusion
Neutron stars are very strange and very interesting interstellar objects we are still
learning new things about. They function and operate very differently from most
other objects in the universe, and are still fairly mysterious.

14. References I used
https://en.wikipedia.org|
https://www.astro.umd.edu
https://www.nasa.gov
http://astronomy.swin.edu.au
https://imagine.gsfc.nasa.gov
https://www.space.com
https://www.britannica.com
https://study.com
https://answers.yahoo.com
https://www.quora.com
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