Presentation On

BLACK HOLES

Contents• Introduction

• History

• Parts of Black Hole

• Classification

• Closest Black Hole

• Largest Black Hole

What is Black Hole?

An unimaginably dense region of space where space is curved around it so completely and gravity becomes so strong that nothing, not even light, can escape.Mass is so great in such a small volume that the velocity needed to escape is greater than the speed light travels.

History

The idea of black holes was rediscovered in 1916, after Einstein published his theory of gravity. Karl Schwarzschild then solved Einstein's equations for the case of a black hole, which he envisioned as a spherical volume of warped space surrounding a concentrated mass and completely invisible to the outside world.

Parts of a Black Hole

There are three main parts to a black hole.

Singularity Outer Event Horizon Inner Event Horizon

The Singularity is the very center of a black hole. It is where the gravity is the strongest. Singularity is just a big word that means "squashed up star".

The Outer Event Horizon is the very outer layer. You would still be able to escape from a black hole's gravity because the gravity on this layer is not as strong as the middle or center layer.

The Inner Event Horizon is the middle layer. This layer's gravity is strong. If it captures you, then you can't escape. The gravity on this layer releases anything that it captures. It would push you toward the center of a black hole where the gravity is very strong.

Classification of Black Holes

Three classifications of black holes: Stellar-mass: 3 to 20 times the mass of our Sun Supermassive: Black holes with millions to billions of times the

mass of our Sun Mid-mass: In between stellar-mass and supermassive

Stellar-mass:

Black holes are made when a giant star, many times the mass of our Sun, dies.Most of the star’s atmosphere is blown into space as a supernova explosion.The star’s spent core collapses under its own weight.If the remaining mass is more than the mass of 3 Suns, it will collapse into a black hole

Supermassive:

Extremely massive black holes have been found in the centers of many galaxies - including our own!

Mid-Mass:

Scientists are finding these in the centers of large, dense star clusters.

Like this globular star cluster, called M15, in our Galaxy.

Closest known of Black Hole

The closest black holes yet discovered are several thousand light-years away. They are so far that they have no effect on Earth or its environment. A supermassive black hole appears to inhabit the center of the Milky Way galaxy, about 27,000 light-years away.

Largest Black Hole known till date

The largest of the nearby galaxies, M87, now has the largest known black hole. It contains 6.6 billion times the mass of our sun and could swallow our solar system whole.

Thank You…!