Sagittarius A*

Scientists from the Event Horizon Telescope(EHT) facility, a collaboration of over 300 researchers, revealed the first image of the black hole at the centre of the Milky Way.
This image of the black hole referred to as Sagittarius A* (SgrA*) gave further support to the idea that the compact object at the centre of our galaxy is indeed a black hole. This strengthens Einstein’s general theory of relativity.
The image is the first visual confirmation that a black hole indeed exists at the center of our galaxy.
- In 2019, the Event Horizon Telescope made history by releasing the first ever image of a black hole M87* – the black hole at the centre of a galaxy Messier 87, which is a supergiant elliptic galaxy.
- The EHT project is a massive telescope array made up of a worldwide network of radio telescopes.
- It integrates data from a combined array of multiple very-long-baseline interferometry (VLBI) sites throughout the world.

blackhole

A black hole is a place in space where gravity pulls so much that even light can not get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying.
Because no light can get out, people can’t see black holes.
Stellar black holes are made when the center of a very big star falls in upon itself, or collapses. When this happens, it causes a supernova. A supernova is an exploding star that blasts part of the star into space.
Albert Einstein first predicted the existence of black holes in 1916, with his general theory of relativity. The term “black hole” was coined many years later in 1967 by American astronomer John Wheeler.
Because no light can get out, people can’t see black holes. They are invisible. Space telescopes with special tools can help find black holes.

Black holes form when massive stars die and their cores collapse. The most common way of black hole formation is when a star runs out of fuel and collapses into its gravitational pull.
There are four different types of black holes – stellar, intermediate, supermassive, and miniature.
- Stellar black holes are made when the center of a very big star falls in upon itself, or collapses. When this happens, it causes a supernova. A supernova is an exploding star that blasts part of the star into space.
- All of a black hole’s mass is condensed into a small point of infinite density at its centre. This point os called singularity

A way in which the universe showcases a black hole is when the black hole interacts with its surroundings.
When the dust particles and matter from the surroundings fall onto a supermassive black hole, it engulfs a part of the surroundings but some of the matter is converted into energy and emitted as electromagnetic radiation that makes the black hole appear very luminous.
This luminosity can be detected on earth thus, giving more insights into these occurrences.

A supermassive black hole is the largest type of black hole, with mass on the order of millions to billions of times the mass of the Sun.

event horizon

The ‘event horizon’ is the boundary defining the region of space around a black hole from which nothing (not even light) can escape. In other words, the escape velocity for an object within the event horizon exceeds the speed of light.

Neutron stars are stellar objects with a mass about 1.4 times that of the sun. Neutron stars are formed when a massive star runs out of fuel and collapses.
When stars four to eight times as massive as the sun explode in a violent supernova, their outer layers can blow off in an often-spectacular display, leaving behind a small, dense core that continues to collapse.
Gravity presses the material in on itself so tightly that protons and electrons combine to make neutrons, yielding the name “neutron star.”

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