What is space?

Is an imaginary measurement helpful?

You can think of it like this. Space is actually nothing. But this idea has started to change. We see why space is called imaginary.

Suppose there is nothing in space. Emptiness throughout. There you are standing in a spacesuit. Where there is no effect of gravitational force, there are no planets-satellites around, there is no problem for you to stand in that space.

But what space is there?
What do we really mean by space?

Let's take a box. The volume of that box is 1 cubic meter. If the box is with you in space, then you can say, there is a space of 1 cubic meter. You can then say that your favorite cat is within that 1 cubic meter space.

We think of the whole universe as a huge cosmic space. And within that space are all galaxies, planets, satellites, black holes, stars, etc. But that place doesn't have six walls like a box. Maybe there is an edge to the universe. But whether that end is made of anything special—it is hard to imagine.

The point is, space is an imaginary object, which cannot be seen, but is helpful in measuring the length, width, height of the object. Even specifying the location of objects requires space. As such, the mantle of space is spread throughout the universe.

Each part of which is seen as a small space. For example, somewhere in the universe there is a galaxy called the Milky Way. And in a special place in that galaxy, the star named Surya is staying with its huge family. Of course, it's not fixed, it's always running around.

Source: New Scientist