The Universe is a very complex place that we hardly come close to understanding. The humbling reality is all of humanity, in it’s importance to us as individuals has insignificant impact on a universal scale. To understand how large the universe truly is we must look at things in terms of the speed of light, and how long it takes light to travel. Looked at in a simple prespective, it takes troughly eight minutes for light to travel from the sun to earth, this distance is one AU (Astronomical Unit).
When we stare into what is called “deep space” or the furthest we can see into space, we can observe at a distance of 15 billion light years. We are literally observing the past, as the light itself took so long to travel to us, the source of the light may not be around anymore. This allows us to determine the age of the Universe must also be 15 billion light years old, at least based on the most modern model for how stars, galexies, and the likes came to be. If the universe were older, we would be seeing light sources from further away.
A quite humbling conclusion to come to. To give an idea of how little we know about the Universe, well to that we can turn to “dark matter”. Dark Matter is basically matter that, when we look at our equations for gravity and compare them to what we are observing in stellar bodies, we find that about 90% of the matter that should be there for these observations, is undetectable.
So yes, the humbling reality is that we live 8 light minutes from a sun, in a universe at least 15 billion light years wide. We also live in a universe in which we cannot account for or detect 90% of the matter that should be there according to our most fundamental laws of physics and gravity.