What is a galaxy?

A galaxy is a huge collection of stars, their solar systems, dust and gas. It is held together by gravity.

Earth is a part of the solar system, which is a small part of the Milky Way Galaxy. All those stars you see in the sky at night belong to the Milky Way.

When you are far away from city lights, some place really dark, you can even see the dusty bands of the Milky Way stretch across the sky.

How many are there?

There are countless galaxies out there. Once, when the Hubble-Space Telescope looked at a small patch of space for 12 days. It found nearly 10,000 galaxies of all sizes, shapes and colours.

Some scientists believe there could be as many as one billion galaxies in this universe!

How do they look?

Galaxies came in different shapes. But the two most common types, based on ones discovered so far, are Spiral Galaxy and Elliptical Galaxy.

The Milky Way is a spiral-shaped galaxy. This type of galaxy has curved arms that make it look like a pinwheel.

Elliptical galaxies, on the other hand, are smooth, and oval shaped.

Just like ours, other galaxies too get their light from stars that inhabit them.

On collision course

There are times when two or more galaxies can get too close and smash into each other. For example, the Milky Way galaxy will someday bump into the Andromeda galaxy, its closest neighbour.

However, this won’t happen for another five billion years at least, and even if it were to happen anytime soon, you wouldn’t notice and spread out at the ends that even if they do bump into each other, the planets and solar systems often don’t get close to colliding.


Picture Credit : Google