Just as there are different types of stars in the course of the evolution of stars, there is another one on the basis of which stars can be divided into several classes and that is the kinematics (Kinematics :The branch of mechanics concerned with the motion of objects without reference to the forces which cause the motion.) of stars.
We all know that our Sun
and all the other stars continue to revolve around the centre of our galaxy
with cosmic dust while maintaining normal speed. This same phenomenon is also
happening in our neighboring galaxies and billions of other galaxies. It is a
normal occurrence in every cosmic object. In this normal course of rotation,
the existence of some stars has been found to revolve independently and
spontaneously without being bound by the gravitational force of the galaxy.
Let's talk about them briefly today.
A.
Runaway Star: This type of star travels with some unusual
speed compared to other cosmic objects around it. This type of star is said to
be due to this unusual cause -
1. An abnormality in the
interaction of gravitational forces between two or more stars within a
constellation causes one or more stars to come out of the constellation and
move forward at very high speeds.
2. When multiple stellar systems or
galaxies move closer or collide with each other, it has an effect on both
systems, and as a result, some stars gain higher speeds, come out of them and
move faster.
3. If a star faces a supernova
explodes in a constellation, it turns into neutron star or black hole. The
other stars in that constellation including the resultant state of supernova explosion
could become Runaway Stars.
However, in addition to
this, multiple factors can also be used to create Runaway Stars. The speed of
this type of star can be up to five times faster than the actual speed of other
normal stars. As per examples we can mention the names of AE Aurigae or MU
Calumbae etc.
B.
Hypervelocity Star: This type of star has a higher velocity
than the Runaway Star. Their speed is about fifty times faster than the normal
speed of stars in space. Some stars have been found to have speeds greater than
the escape velocity (Escape Velocity: The
lowest velocity which a body must have in order to escape the gravitational
attraction of a particular planet, satellite, star or other object.) of
galaxy. They are usually found in large numbers in the center of the galaxy. In
1988, scientist Dr. Jack Hills first suggested the possibility of such a star,
and within a few years, his statement was accepted by scientists.
It is thought that there
may be as many as 1,000 Hypervelocity Stars in our galaxy. More than 20 such
stars have been found in our galaxy and in distant galaxies. The S5-HVSI star
is the fastest moving star ever found. The speed of this star is eighty-eight
times the normal stellar motion of the universe and it is located 29,000
light-years (Light-year: In a year the light goes as far as the distance)
away from the Sun in the Grus constellation. One surprising fact about this
star is that, it was a member of our galaxy in the past. In addition, some very
fast moving stars have been found which were born in a small galaxy called
Large Magellanic Cloud but they have been discovered in our galaxy. All the
Hypervelocity Stars, found in our galaxy so far, have come from our neighboring
Large Magellanic Cloud.
The reason for the origin
of such a star is said to be that when the Binary Star (Association of two
stars) and the large black hole face each other, the black hole actually pulls
one of the two stars towards itself by intense gravitational force and the
other star accelerates and moves away from its old position. Sometimes neutron
stars also become Hypervelocity Star. As an example we can mention the name of
RXJ-0822-4300, the neutron star.
C.
Inter-Galactic Star: This type of star is also called
Inter-Cluster Star or Rogue Star. They are a type of star that is not bound by
the gravitational force of any galaxy. Although the source of all these stars
would be a galaxy but later they have come out from there. The search for inter-galactic
stars was first discovered by the Hubble Space Telescope in 1997 in Virgo
Constellation.
How the Inter-Galactic Star
originated is shrouded in mystery today. However, attempts are being made to
solve that mystery through some scientific explanations. The most common
hypothesis in this regard is that when two or more galaxies collide, there is
some effect on the equilibrium state of gravitational forces between the two
galaxies, and the smaller galaxies have the greatest effect. In this state,
stars come out of small galaxies and move forward at a tremendous speed in the
vast emptiness of space.
The second concept has a
lot in common with the origin of Hypervelocity Stars. The main difference,
however, is that in the first case Binary stars take part but in the second
case the sum of more than two stars is involved. It is estimated that our
galaxy produces one intergalactic star every 1 million years.
D.
Halo Stars: This type of star is one of the earliest
stars in space. Hello stars are mostly found in spiral galaxies. Although their
age cannot be determined, it is assumed that the age of some of the Hello stars
is the same age as our universe, that is, they came into existence at the time
of the creation of the universe. That's why they have very little fuel. These
stars continue to orbit the galaxy in elliptical orbits. However, their orbits
are not always in the same plane as the galaxy, sometimes they rise quite a bit
above the galaxy plane and sometimes they go down a lot. It is thought that,
they may gain high momentum as they orbit the galaxy in different plane.
An example of such a star
is the Kapteyn's Star which is located 12.8 light years away from our Sun. In
the same way that all the stars in the galaxy revolve around the center of the
galaxy, this star revolves around the center of the galaxy along its precise
orbit in the exact opposite direction. About 45 Halo stars have been found in
our galaxy so far.
All of these stars are
discussed here because they have gained greater momentum than the other stars
around them, but it is true that they, like other stars, are at a certain stage
in their evolutionary path. Apart from this, there are many other types of
stars scattered in mysterious parts of this endless universe which we have not
seen today. But the relentless inquisitiveness of the people will find them
right now or in the distant future. In this way, the unknown things of this
infinite space, its thrilling history will come to light little by little
across the various interconnected connections. It is this belief that keeps
people engaged in the relentless quest to know the unknown.
DECLARATION:
All The Images Have Been Sourced From Google.
