No matter how hard people try, it will never be possible to see all of outer space in its entirety.
The space is big, very big. It is large enough to fit the Earth, the Sun and all other planets with stars, writes Space.com.
Not so long ago, people thought that when they looked at the night sky, they saw the entire cosmos. That was until the advent of Edwin Hubble. He was an American astronomer, and what he learned was so amazing that NASA named the famous Hubble Space Telescope after him.
Almost 100 years ago, Edwin Hubble observed small, blurry spots of light hidden among all the visible stars. No one was exactly sure what they were, but Hubble discovered that these spots of light were made of stars and, more importantly, they were far away.
With this discovery, scientists’ understanding of the cosmos has changed radically. The stars that we see in the night sky are part of the Milky Way galaxy, a galaxy where all humans live.
The specks of light that Hubble studied were other galaxies, each filled with stars, planets, and a host of other space objects.
As it turns out, the space is much larger than previously thought. The part of space that we can see is called the observable universe. The observable universe can even be measured.
The distance from one side to the other is 93 billion light years. Such a figure is hard to imagine even for astronomers. It’s like making about 300,000 circles in the Milky Way, our sun has only made 20 circles in its entire life.
Furthermore, the observable universe is focused on us, because we are at the center and peering out into space. Aliens on another planet, in a distant galaxy, would have their own observable universe.
But is there an end? Are there an infinite number of galaxies? Or do they eventually run out? Scientists do not yet have clear answers to these questions.
Some scientists suggest that you will most likely simply forever pass galaxies in all directions. In this case, the universe would be infinite.
Others believe that it is entirely possible that the universe will eventually wrap around itself, so that if you went on a space voyage, you would be back where you started from a different point.
To better understand what is at stake, imagine a globe and that you are a creature that can only move on the surface. If you start walking in any direction, like east, and just keep going, you’ll end up back where you started.
If this happened in the universe, it would mean that it is not infinitely large. Anyway, you could never reach the end of space or the universe.
Currently, many scientists believe that it is unlikely that the universe has an end – a region where galaxies stop or where there would be some kind of barrier marking the end of space. But no one knows for sure.