Have you ever thought or heard of an
object that contains the mass of sun? And the size of such an object is nearly
a size of a city? Yes, such objects occur in the universe. They are called as
neutron stars. There are nearly 10 types of neutron stars they are neutron stars, black dwarfs, white
dwarfs, brown dwarfs, red dwarfs, yellow dwarfs, blue giants, red giants, blue
supergiants and red supergiants. And an interesting fact about
neutron star is that a single teaspoon
of it weighs a billion tons, indicating that they are so dense. Neutron
stars can spin as fast as 43,000 times per minute. Neutron stars pack
their mass inside a 20-kilometer (12.4 miles) diameter.
Neutron stars are formed when giant
stars die in supernovas. Generally Supernovas
are of two types, one occurs at the binary star system and the other occurs at
the end of the single stars lifetime. As the star runs out of fuel some of the
mass of the star starts to move towards the centre (towards the core). At this
time the core becomes too heavy and the star cannot withstand its own
gravitational force. So the star starts to collapse with electrons and protons
which melt to form neutrons and they are called neutron stars. Gravity in
neutron star is 2 billion times stronger than the gravity on the earth. They
transfer material in the form of stellar winds, they move along the magnetic
poles causing X-Ray pulsations as it is heated. Sometimes the materials move
with the speed of light.
of neutron stars:
Low-mass X-ray binaries (LMXB).
Intermediate-mass X-ray binaries (IMXB). High-mass X-ray binaries (HMXB).
Common known types are pulsars and magnetars.
are spinning neutron stars which emit a
narrow beam of radiation. The beam may sometimes sweep across the earth making
the astronomers to think it as the flashing object. All pulsars are neutron
stars but not all neutron stars are pulsars.
are the type of neutron stars that have high magnetic field. One of the known
magnetar is SGR 0525-66. SGR 0525-66, in
the Large Magellanic Cloud, located about 163,000 light-years from Earth,
the first found (in 1979).
Black holes Vs neutron stars:
Both black holes and neutron holes are the same; they
are the product of dying stars. The difference lies in the mass of the parent
star. If a star with a mass 1.4 to 3 times than that of sun dies a neutron star
is formed. If a star with a mass greater than thrice the sun’s mass dies a
black hole is formed.
If two neutron stars collide there is
a possibility that a black hole may be formed. In a neutron star, electrons and protons
combine to form neutrons, and neutrons have no space left to move around.
According to the Pauli exclusion principle no two electrons can occupy the same
space, and so, neutrons prevent further collapse
In a black hole, gravity dominates
and so there is nothing left to halt further collapse. A black hole is thought
to be a point source, as all the mass resides within a space of zero curvature.
The size of a black hole is thus defined by the Schwarzschild radius i.e., the
radius beyond which the escape velocity exceeds the speed of light, called the.
Our universe, still have many interesting
things that are discovered and which are yet to be discovered.