Universe
The entire world, visible and invisible to us, is called the cosmos. Earth, moon, sun, planets, star circles – all are part of this cosmos. The space between these planets and stars is also a part of the cosmos. Distances in the universe are extreme. The average distance between the Earth and the Moon, the closest celestial body to the Earth, is 3 lakh 85 thousand kilometers. The distance between the earth and the sun is 149 crore 80 lakh kilometers. Sun is also a star.
How big is the universe
About 6 thousand billion years ago, all the matter in this cosmos was a single mass, the matter was very dense and thick and occupied the same space as the present solar family. When the heat in this cosmos reached its maximum due to extreme heat, it burst into flames and there was a great explosion. Due to that expansion, the heat of the matter decreased and atoms, molecules, then hydrogen, helium, and oxygen were formed. In this way, the disintegrated cosmic matter was reintegrated due to the force of gravity, and stars and galaxies were formed. Those galaxies are still moving away at the same speed that they initially acquired. A small cosmos that moves away expands further.
What is a light year?
To measure these distances in the cosmos, scientists invented a new standard called the light year. A light year is a distance traveled by a light year. Light travels 3 lakh kilometers per second. In this way, it travels 180 lakh kilometers per minute, 108 crore kilometers per hour, 2592 kilometers per day, and 9 lakh 50 thousand crore kilometers per year. This distance is called a light year.
What is the Milky Way?
On the night of Amavasya, a bright white cloud is seen dividing the clear sky into two parts. It is known as the Milky Way or the Milky Way or Milky Way. In this nakshatra mandala, there is a star called our sun. The diameter of the Milky Way is one hundred thousand light years. The Sun is 30,000 light years away from the center of the Milky Way. Scientists have said that there are more than 10 thousand crore stars in this Milky Way. There are billions of galaxies like our Milky Way in the universe.