Quasars: The Horrifying Monsters of Heat.

Image Credit: NASA. Quasar.

What Are Quasars?

Quasar is the short form for '' quasi-stellar radio sources'' which are the brightest and most energetic objects in the Universe which are powered by supermassive black holes at the center of galaxies. It is an active galactic nucleus (AGN), where supermassive black holes with millions and billions of masses are rapidly accreting matter and releasing intense radiation across the electromagnetic spectrum which are radio waves, gamma rays, UV, X-rays and visible light.

Characteristics of a Quasar:

Brightness: Are They Bright or Dark? 

Image Credit: NASA. Milky Way Galaxy.

Quasars can outshine an entire galaxy, and they are 1000 times brighter than the Milky Way galaxy. 

Power Source: What Is Giving It This Much Power?

Image Credit: NASA. Supermassive Blackhole.

The accretion of gas, dust and matter by a supermassive black hole is the source of a quasar's power.

Emission of Energy:

A quasar can lonelily emit energy of 100 galaxies' energy combined.

Lifeline:

A quasar is active for 10-1000 million years before dimming.

Working: How Do Quasars Work?

A galaxy is formed with a supermassive black hole in the center of it. The gas, dust and stars start falling in the accretion disk of the supermassive blackhole. The material starts to heat up to millions of degrees. This creates an extremely luminous radiation jet. These jets of energy sometimes shoot out from the poles at the speed of light. This jet is known as quasar. 

Structure of a Quasar:

The structure of a quasar consists of a supermassive black hole in its center and accretion disk which is a glowing and bright disk of hot matter. The broad line region (BLR) are hot gas clouds which emit wide spectral lines. Torus is donut shaped gas or dust which obscure some wave lengths. Jets are twin beams of high-energy particles shot at near light speed. Host galaxy is often a large elliptical galaxy undergoing intense change.

Discovery of Quasars:

The first quasar was discovered in 1960s as strange radio sources with a star like appearance. The first quasar identified was 3C 273, 2.4 billion light-years away.

Why Are Quasars Important?

Cosmic History:

Quasars are the fossils of the early Universe.

Galaxy Evolution:

Quasars affect how galaxies grow via feedback which means that they can suppress or trigger star formation.

Measuring Distance:

Quasar's redshift helps measure cosmic expansion and dark energy.

Black Hole's Studies:

Quasars help us understand how black holes grow and behave.

Map Structure:

Quasars are used to detect intergalactic matter and dark space structures.

Types of Quasars:

there are several types of quasars which are mentioned below:

• Radio loud quasars emit strong radio waves via jets.
• Radio quiet quasars emit luminous energy but no strong radio waves.
• Blazars are quasars which directly points its jets towards Earth. these jets are extremely bright.
• Optical quasars are visible in light.
• X-ray quasars are those quasars which are detected by its high X-ray emissions.
• Obscured quasars are the quasars hidden behind dust. These quasars are found by infrared and X-rays.

Fun and Rare Facts About Quasars:

• Quasars were brighter than anything in the early Universe.
• The light from the farthest quasar we can see took over 13 billion years to reach us.
• Quasar SDSS J0100+2802 has a black hole over 12 billion solar masses.
• Some quasars are gravitationally lensed which are magnified by foreground galaxies.
• A “quasar storm” can affect its entire galaxy, blowing out star-forming gas.
• They look like stars through a telescope, but they are not stars.
• Quasars existed mostly in the early universe (10–12 billion years ago). We see them now because their light took billions of years to reach us.
• Quasars are like black holes eating matter and converting it into light.
• Quasars are often triggered when galaxies collide.
• Observing quasars is like looking back in time because we see them as they were billions of years ago.
• Quasars are a temporary phase in a galaxy’s life but once the black hole stops feeding, the quasar fades.
• Light from quasars is often bent by massive objects which helps scientists in studying dark matter.

In short, quasars are the brightest monsters from past. Quasars are the brightest objects.