Galaxies are huge spinning areas in space which contain all types of cosmic things like dust, planets, stars, black holes (at the center), and etc.
We live in the Milky Way Galaxy. It’s shaped like a big spiral with arms that stretch out. Our solar system is located in one of those arms, far from the center. If you’ve ever seen a band of light across the night sky, that’s part of the Milky Way.
There are billions of galaxies in the universe. Some are small, some are huge. They come in different shapes:
- Spiral galaxies (like the Milky Way) look like pinwheels
- Elliptical galaxies are round or oval
- Irregular galaxies have no clear shape
Many galaxies, including ours, have a supermassive black hole in the middle. It’s very heavy and pulls stars and gas around it.
Galaxies are huge. The Milky Way is about 100,000 light-years wide. That means light takes 100,000 years to cross from one side to the other!
There are billions of galaxies in the universe. When we look deep into space with powerful telescopes, we see more and more — like looking at grains of sand on a beach.
Some questions
How Do Galaxies Form?
Galaxies started forming billions of years ago, shortly after the universe began. Tiny clumps of gas and dust came together because of gravity. Over time, these clumps grew bigger, forming stars and eventually entire galaxies. Some galaxies formed alone, while others grew by merging with smaller ones — like cosmic building blocks coming together.
What Happens When Galaxies Collide?
Galaxies often move through space and sometimes crash into each other. But because stars are so far apart, they rarely hit. Instead, the galaxies mix and change shape. This can create new stars and even form a bigger galaxy. Our Milky Way is expected to collide with the nearby Andromeda Galaxy in about 4 billion years — and they’ll likely merge into one giant galaxy.
What Is a Galaxy Cluster?
Galaxies don’t float alone. They gather in groups called clusters. Some clusters have just a few galaxies, while others have thousands. These clusters are held together by gravity and can stretch across millions of light-years.
What Is a Light-Year?
A light-year is the distance light travels in one year — about 9.5 trillion kilometers. When we say a galaxy is “millions of light-years away,” it means the light we see from it today actually left that galaxy millions of years ago. So looking at galaxies is like looking back in time.
>What Is Dark Matter?
Galaxies seem to have more gravity than their visible stars and gas can explain. Scientists believe there’s something invisible called dark matter that adds extra pull. We can’t see it, but we know it’s there because of how galaxies move and behave.
*Some of the parts of the website is inspired by NASA's official website*
Designing ideas credit goes to NASA (Respect!)