*Know why stars twinkle and Why do they come out only at Night?

Aakrity Chapagai
3 min readAug 18, 2020

Actually stars don’t twinkle at all. They only appear to twinkle. This is why it happens. The light of the stars reaches us by passing through the atmosphere of the Earth, which is made up of many layers of gases.

These gases have different temperatures , pressures and several pockets of hot and cold air. When light passes through these gases, it gets slightly affects by these factors and bends a little this way and that. When we view this wavering light from the ground, it appears that the starts are twinkling.

2.Why do stars only comes out at night ?

The stars are there in the sky both during the day and at night. During the day, the sun shines so bright that we cannot see the other stars present in the sky.

At night , when the sun goes down and sky is dark, the light of the stars can be seen. Have you noticed how stars start to appear as the Sun starts to set ? Do you know that the Sun is also a star ? It shines brighter than the other stars as it is very close to the Earth while the other stars are far a away.

3. What is a star ?Why does it shine ?

A star is a huge ball made of hot gases. The main gas in a star is hydrogen. The hydrogen atoms are constantly bumping into each other with so much force that it makes the hydrogen burn. This reaction produces lots of heat and light , Which makes that star shine.

When hydrogen atoms collide with each other to give out this light, another gas called helium is also produced in the process. So, a star is basically made up of two main gases; hydrogen and helium.

4.How far are the stars from Earth?

Stars are billions of kilometres away from each other. Yes, that sounds like as awesome distance. Isn’t it ? Since the stars are so far away, it takes huge amount of time for the light of the star to reach us. Depending on the distance of the star from the Earth, the light of the star can take seconds, minutes and sometimes even years to reach us !




5. What is a light year ?

Light year is the distance that the light travels in one year. So, if we read somewhere that star is 4 light years away, we know what it means right ? It means that it will take 4 years for the light of that star to reach us.

6.Sun is a star , what about Moon ? Is Moon also a star ?

Moon is not a star. Moon is not as big as a star should be. It is a natural satellite of the Planet Earth. A satellite is a small, round ball that resolves around a planet. As we now know, a star is a massive ball made of gases that react with each other to give out heat and light.

But there is no such chemicals reaction taking place on the moon. Since it doesn’t burn any hydrogen, there is no light of its own as well. So, the moon doesn’t qualify to be a star!