The skies and space reach farther than we are even able to travel. Of course we can assume that the vastness is above our comprehension. Trying to understand how big the universe is or how far space goes would be like trying to explain the internet to an ant. It just is not feasible to even try.
If you've ever seen a traffic light up close, you know that they are a LOT bigger than you think they are, because you see them from so far away most of the time. The same thing is true in space. We see the moon, but we don't understand how GIANT the moon actually is. Other planets, galaxies, whatever, they are out there and they are so big that we can't really grasp how big.
Yes, things in space are unimaginably huge. Our perception makes stars look like tiny dots in the sky, but they are massive suns lightyears away. Our sun looks like a tiny dot to other planets. It is all about our perception. We need incredible telescopes to truly appreciate their size.
While the dimensions of objects in space might be too large for the average human to comprehend, astrophysicists are able to give us hard numbers and facts for our universe. Neil DeGrass Tyson, American astrophysicist, director of the Hayden Planetarium, hosts a podcast called StarTalk that breaks down the vastness of space in a way that the layperson can understand, while still managing to preserve the beauty and wonder of the universe.