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A Brief Comprehension on the Universe

To answer what the universe is, we can say that the universe is everything that we know of, or we can imagine of, from all the living to the non-living things.


Anything that can be felt by us comes within the universe. To understand it in a simpler form, the universe is composed of galaxies, stars, planets, asteroids, meteorites and all the other components in space. To link all these entities together, we can look at things as the galaxies comprise stars, planets and other dust particles. All such galaxies come within a common universe. 

The universe was formed many years ago. Earlier, it was thought that the most important components in space are the Earth, the Sun and the Moon. But with the advancements in science and broadening the horizon of the human mind, we came to know about the universe. Today, it’s a well-known fact that the Earth is nothing more than a speck when compared to the vastness of the universe. 

How was the universe formed?

When the universe was discovered, several theories were given by different scientists about the formation of the universe. But the most popular and the most accepted among them was the Big Bang theory. 

Big Bang Theory

The name of this theory was derived from the ‘Big bang explosion’ that resulted in the creation of the universe. The Big Bang theory explains that the universe is about 13.7 years old. Originally, the universe consisted of a hot ball. Within this ball, an explosion took place. This explosion was termed the big bang explosion. 

After the explosion, the universe began to expand, and it is in the same expanding state even today. Today, everything that we know as a part of the universe was formed as a result of this huge explosion. 

The very step after the explosion happened was the expansion of the released gases. When carbon dioxide and hydrogen are combined, they condense to form oxygen and water. This water fell as rain. After the formation of oxygen, oxidation processes began. Otherwise, only reduction used to take place.

The basic concepts


The stars are chunks of gases held together by gravitational force. They are luminous objects which means that they emit their light. The sun is also a star.

The sun is visible during the day, while the smaller stars are visible during the night. This is because the stars that we see during the night are very far away from the surface of the Earth. Their light reaches our eyes when the sun is no more visible to us than is in the night sky.


Planets are one of the astronomical bodies that have significant mass to have their gravitational force. Planets are non-luminous objects and do not have their light. They are visible due to the reflection of light that is emitted by stars. 

Planets move around the star in fixed orbits. Often, planets have satellites that revolve around the planet in orbits. For example, our Earth has its satellite, the moon. 

Moon is a natural satellite. Planets also have artificial satellites that are man-made. On the other hand, natural satellites are the ones that were made in some of the other processes that took place in the universe itself, that keep orbiting around their particular planet.

What is meant by the Solar system?

What is the universe without the solar system? The solar system has been derived from the word ‘sol’, which means the sun, which is the centre of the solar system. In the solar system, the sun is at the centre and all the other bodies, such as the planets, satellites, etc., in the solar system move around the sun in orbits. All the objects are stable due to the strong gravitational force between them that keeps them bonded together. However, there’s a slight difference between the orbit of the planets and other bodies. The planets orbit the sun directly, unlike the other bodies that orbit the sun indirectly.

Measurement of distance between the sun and the planets

The distance is measured between the sun and the planets in the unit called light-years. It is defined as the time taken by light to travel from the stars to the Earth, and light takes years to travel from the sun to reach our eyes. It implies that when we are looking at a star, we are actually looking back in time. This is because the light the star emitted many years back is visible to us today. 

To be precise, 1 light year = 9.46 × 10^12. Now, you can well imagine how long it takes light to travel from the stars to the Earth.


What is the universe ? has been one of the most mysterious questions for humankind? Although today, after ages, we as humans have come a long way and solved many unique mysteries of the universe, there are still miles to go ahead. There seems to be no end to this path. But, at your level, nothing can be asked beyond what is given in the above article.

Make sure to be thorough with all the facts and information, and you’ll be able to answer every question easily and within less time.


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