Category Science

What are Lagrangian orbits?

A tristar system appears to be clearly an unstable system at first glance, since minor gravity disturbances in the system will cause one of the orbiting stars to advance on the other leading top collision and ultimate merger of the two orbiting stars.

However, there are two points in such an orbit where there is comparative stability and safely from any such catastrophic collisions. These points are called the Lagrangian points. Located 600 ahead or behind the other orbiting body, the Lagrangian points form a perfect equilateral   triangle with the central star. The stars located at Lagrangian points in such an orbital configuration would then be said to be in a Lagrangian orbit. A Lagrangian orbit can apply to planets also e.g. the Lagrangian points of Jupiter containing the ‘Trojan’ asteroids.

What is binary star system?

In a binary star system, there are two stars, both orbiting their common bary centre.

The stars in a binary star system are separated by about 10 to 20 a.u.

Do binary stars actually exist?

It is estimated that fifty percent of all stars in the Universe are continued in binary systems.

Why is the study of binary star systems of importance to astronomers?

Applying Kepler’s laws (linking stellar masses with time and distance) to binary systems, the stellar masses of the component stars can be directly calculated. This is of utmost importance to astronomers.

How do astronomers keep track of the orbits of the individual stars in a binary star system?

While observing binary star systems one star is considered stationary and the orbit of the other companion star around it is plotted. From this information the actual paths of both stars can be computed.

What is a tristar system?

A tristar system is a system in which two companion stars (sharing a common orbit) orbit a central star.

Do tristar systems actually exist?

No tristar systems have been detected so far. However, if such tristar systems do exist, then the orbit would have to be large in relation to the diameters of the stars to avoid serious tidal effects and ensure stability of the system.

What is a galactic Black Hole?

A very compact and energetic microwave source exists at the centre of the Milky Way Galaxy. There is a theory that this is caused by a giant Black Hole or galactic Black Hole having a mass of 100 million stars. There is also another theory that there are such galactic Black Holes at the centre of every galaxy. For example, the galaxy NGC-6240 which is 300 million light years away from earth is suspected to contain a black hole 100 billion times as massive as the Sun.

To what extent will matter in a Black Hole collapse?

Matter in a black Hole will continue to collapse indefinitely until, in principle, it is compressed into appoint of infinite density Known as a singularity (or Schwarzchild singularity).

Continue reading “The Stars”

What is the Stationary Limit for a Black Hole?

The Schwarzchild radius applies to rotating as well as non-rotating Black Holes. However, rotating Black Holes bulge at the equator just like other rotating bodies and this creates a centrifugal effect with the emergence of another boundary outside the Schwarzchild radius called the Stationary Limit. In a non-rotating Black Hole, the Stationary Limit coincides with the Schwarzchild radius.

What is the significance of the Stationary Limit?

An object approaching a Black Hole is in no danger of falling into the Black Hole if it stays outside the Stationary Limit. If the object approaches the Black Hole within the Schwarzchild radius, it is certain to fall into the Black Hole. However, an object approaching within the Stationary Limit but remaining outside the Schwarzchild would be semi trapped, meaning that it may be able to escape but only by moving in the direction of rotation of the Black Hole and using the Black Hole’s rotational energy to hurl the object outside the Stationary Limit. 

What is the maximum possible size of a Black Hole?

There is really no maximum limit to the size of a Black Hole as it can grow bigger and bigger by sucking in more mass from its surroundings.

How does a black Hole get the enormous energy to sustain itself?

All matter falling into a Black Hole will have about 30% of its mass converted into radiation immediately. This is far more than in any fusion reaction. The remaining matter is further converted into energy to sustain the intense gravitation field of the Black Hole. All the matter entering a Black Hole would end up as energy in the above two stages.

What is the event horizon?

Since no light can escape from a Black Hole beyond the Schwarchild radius, the Schwarzchild radius represents the limit up to which we can observe the events happening inside a Black Hole. Any event occurring within the Schwarzchild radius cannot be seen by an observer situated outside the Black Hole. Hence the boundary of the Black Hole denoted by the Schwarzchild radius is also called the event horizon of the Black Hole.

What is a mini Black Hole?

A mini Black Hole is one that has Shrink to a small size. The matter in it continues to be intensity dense as in normal black Hole.

What would happen if a mini Black Hole hits the Earth?

A mini Black Hole hitting the Earth would instantaneously punch a hole through the Earth and continue on its journey through space. The hole punched in the Earth by the mini Black Hole would close up immediately and any affected areas on the surface would be limited to the points of entry and exit of the mini black Hole. However, the mini Black Hole would pick up some matter from the Earth.

What would happen if a slowly moving mini Black Hole enters a very large body?

There is a possibility that a slowly moving mini Black Hole further slow down and even get trapped while passing through a very large body. In such a case, the mini Black Hole will continue to consume matter from its host body and grow, completely consuming the host body eventually.

Do Black Holes rotate on their axis like other heavenly bodies?

Yes.