The Universe

What do you really need to know about our Universe?
I came up with this idea to write my knowledge about this particular topic. The universe.

In the beginning..
If the universe really did begin with a Big Bang, then the galaxies in space should still be moving away from each other. Like debris thrown out in all directions from an explosion. But, What Is the Big Bang Theory? The phrase "Big Bang Theory" has been popular among astrophysicists for decades. It is the Explanation about how the universe began. A big bang theory is the ball expanded which said as a tiny , very hot ball about 15,000 million years ago. The ball expanded or grow rapidly, like a balloon being blown up.

When we look up at the sky on a clear night, We are looking out into the universe which we think is the heaven. Like seriously? Most of the universe is just a vast ocean of empty space, But did we know that there are islands in the ocean? and It is called galaxies. A galaxy is a huge group of stars,millions of millions of kilometres accross. Each star that we can see from earth is in our galaxy ,which is called as Milky way.

What is the shape of our galaxy ?

Maybe someday, One of us here, humans Will travel out to the galaxy. Isn't amazing? If they do, They will see a huge,slowly spinning white spiral-shaped disc.
Most of the galaxies are spiral but others are egg-shaped or also known as Elliptical. A third type of galaxy, Irregular, has no regular shapre at all.
Elliptical galaxy , Spiral Galaxy and Barred spiral galaxy.