For man is simply impossible to imagine the actual size of the Universe. We not only don't know how big it is, but we can hardly even imagine how much it can stretch. If we start to depart from the Earth, we will understand why this is so. The earth is a small part of the Solar system. The Solar system includes the Sun, planets orbiting the Sun, asteroids, representing small planets, and meteors.
All our Solar system, in turn, is a small part of a large star system, called "galaxy". The galaxy is made up of millions and millions of stars, many of which are significantly larger than our Sun and have their own solar system.
So, all the stars we see in our galaxy and which we call the "milky Way"are "suns". The distance between them is measured in light years, and not in kilometers. One year a ray of light passes over 11 000 000 000 000 km. alpha Centauri is the nearest and brightest star is located at a distance of more than 46 000 000 000 000 km from us. But let's imagine the size of our galaxy. It is believed that its diameter is 100 000 light years. This means 100 000 times on 11 000 000 000 000 km
But our galaxy in turn is a small part of another, larger system. Outside the milky Way, probably there are millions of galaxies. But perhaps all of them together form a more substantial system.
That is why it is hard to imagine the size of the Universe. By the way, scientists believe that the universe is expanding. This means that the distance between the two galaxies in a few billion years will be doubled.
The Milky Way
The light from many stars in our Galaxy merges in
hazy light bar
crosses the sky. It was called the milky Way.