A world beyond life

Once upon a time there was darkness everywhere. In this darkness, there was only a small spot containing a lot of power and energy. One day it burst and formed a universe.

Universe

The universe is everything like: stars, galaxies, planets, black holes, you, me, energy, matter and even time.

Are you ready to know the details of these objects!

Stars

When gas and dust combine together due to gravity, they form stars. It takes about millions of years to make a star.

Planets

After the star formation, there is always some matter left around the stars. This matter keeps on combining and forming planets. That’s the reason why earth is revolving around the sun(a star).

Galaxy

The galaxy is a group of stars, planets, dust, gasses and black holes. And these all objects stay in a group due to gravitational pull–the force of attraction between all masses in the universe.

Black holes

These are holes in the space where gravity is so strong that even light can’t escape from them. Black hole is formed when a star collapses in itself.

If black hole is black then how do scientists know it’s present?

They know this because its gravity keeps on pulling dust and gasses in itself till it fills enough and bursts. And one more thing is: when a black hole and a star are revolving near each other, black holes consume energy of stars that produces a lot of light.

Will the universe be of the same size as it is today?

Once there was a scientist named Edwin Hubble, he used the world’s largest telescope and observed that galaxies are expanding and it will keep on expanding due to a mysterious force called dark force. This force works oppositely as gravity means that gravity pulls everyone and dark force pushes everything away.

How did scientists know that the universe came from a tiny spot?

Belgian astronomer Georges Lemaître used Hubble‘s amazing discoveries to suggest an answer to this astronomy question. He said that if the universe is expanding then billions of years ago, it might be so small.

The space is really big! How do scientists measure distance there?

There are different ways of measuring distance there such as:

• Trigonometry
• Parallax
• Standard candles
• Supernova brightness
• Galactic red shift

Wait! We are going to understand them one by one.

Trigonometry

It’s like the trigonometry that you use in school. But it is only used for small distances.

Parallax

It’s the real size and distance of objects to one another and the distance of the size of objects from the observer’s eye.

Standard candles

We can measure the magnitude of a star by its mass. And by comparing this magnitude( how bright it looks to us) we can calculate distance.

Supernova brightness

It’s a two star system. In this one star dies and other lives. Dead star take energy from the living one. When it’s taking energy, it releases a lot of light. So scientists measure this brightness and calculate the distance of galaxies.

Galactic red shift

When light is moving away from us it looks red and when it’s coming towards us it looks blue. This is called red shift. By plotting different red shifts and known distances, it’s possible to know the distance of far galaxies.

Why are some planets large and some are small?

Some planets are small due to heat. In high temperatures, atoms and molecules of the planets escape that’s the reason why mercury is small.

What’s the reason for the difference in gravity?

Some planets have more gravity than others because of their masses. More mass means more gravity. That is the reason why the moon has less gravity than earth.

Why do some planets have an atmosphere and some Don’t?

It’s also due to the heat. When there is more heat, atoms move with very high speed so they can’t form an atmosphere.

Does life exist somewhere else?

Well, yet no planet has been discovered that can have life but it’s possible that some planets may have life. Who knows!

Just imagine yourself as an ant. You are in a building and you are looking for a new life. You couldn’t find any life in that building and you are saying “we have searched dozens of floor tiles, we haven’t found any life”. We are just ants in front of the entire universe and we have just researched a bit but it’s not enough. So we can’t conclude that life exists somewhere or not.

Last day of this universe

There are many hypotheses regarding the last day but a hypothesis named ” Big Freeze”is gaining the ground. It says: the universe will keep on expanding and one day the energy needed for the star formation will reduce to zero and then black holes will dominate and as time passes, they will also vanish by emitting Hawking radiation– it’s a radiation that reduces energy and mass of black holes. Because of this radiation, black holes will not have any energy left so they will shrink and ultimately vanish.