What is the outside of the space?
The outer boundary of geospace is the magnetopause, which forms an interface between the Earth's magnetosphere and the solar wind. The inner boundary is the ionosphere.
First, some simple answers: space is everything in the universe beyond the top of the Earth's atmosphere – the Moon, where the GPS satellites orbit, Mars, other stars, the Milky Way, black holes, and distant quasars.
The trite answer is that both space and time were created at the big bang about 14 billion years ago, so there is nothing beyond the universe. However, much of the universe exists beyond the observable universe, which is maybe about 90 billion light years across.
The Universe is thought to consist of three types of substance: normal matter, 'dark matter' and 'dark energy'. Normal matter consists of the atoms that make up stars, planets, human beings and every other visible object in the Universe.
Scientists now consider it unlikely the universe has an end – a region where the galaxies stop or where there would be a barrier of some kind marking the end of space. But nobody knows for sure.
If space ends, what's on the other side? A. If space is infinite, there is nothing on the other side. If space is finite because it has been bent around upon itself because of gravity, then again there is nothing on the other side of it because there is no seam.
Astronomers have determined that our universe is 13.7 billion years old. How exactly did they come to this precise conclusion?
No, they don't believe there's an end to space. However, we can only see a certain volume of all that's out there. Since the universe is 13.8 billion years old, light from a galaxy more than 13.8 billion light-years away hasn't had time to reach us yet, so we have no way of knowing such a galaxy exists.
As far as we can tell, there is no edge to the universe. Space spreads out infinitely in all directions. Furthermore, galaxies fill all of the space through-out the entire infinite universe. This conclusion is reached by logically combining two observations.
What does out of space look like?
What does Space really look like? - YouTube
Unfortunately, since universe is technically expanding faster than the speed of light (due to the expansion of space between matter), it is theoretically impossible to ever reach the “edge” of the universe, since it will always be moving away faster than we could ever move towards it!