Why observing the universe is difficult?

Why observing the universe is difficult? The reason for that is that we are living inside the universe. That thing denies us getting information outside the universe.  And because of the same reasons getting observations of the Milky Way is difficult. 

We can think that the situation is the same as we are living in the house. But ever visit outside. In that case, we can see and observe things, what is happening outside that house. We see other houses. But we never see the shape of the house where we are living. We might think that the other houses are similar to our house. 

The most difficult object in the sky for research is the center of the Milky Way, which is our galaxy. The supermassive black hole, Sagittarius A is in the middle of cosmic dust and other particles. So we can see the Sagittarius A only because it sends the gamma-ray impulses. Normally Sagittarius A is mentioned as a radio source. But also X- and Gamma-ray observations are needed to confirm that there is a black hole. But in some theories, the Sagittarius A is a group of black holes rather than one supermassive object. 

And the fact is that we are never seen Milky Way itself because we are in the middle of the spiral structure of that galaxy. For making observations of the Milky Way itself we must go outside the spiral structure of that giant galaxy.

Or if we are sharp all galaxies are giant. Even the smallest elliptic galaxies are the size of ten percent of the Milky Way. I don't know are those people who published that information mentioned the center bubble of our galaxy? But the size of those galaxies is light-years. And we have not traveled even light-year from the Earth. So every galactic structure is a little bit too big for the technology, that humans are using. 

When we are seeing images, that are portraying the Milky Way, we must realize that those images are portraying other galaxies. Or they are made by using computers by using data. That is collected from the gravitational effect of the particles. But getting real images of the Milky Way requires traveling outside the galaxy.  

And the same way we must travel outside the universe if we want to observe it as the entirety.  We think that the universe is the ball because if its origin is in the Big Bang. That means the shockwave travels in the form of the ball around that point. During the Big Bang visible material is released to the universe from one point. 

And some people have thought. That the Universe itself could be like a giant spiral galaxy. So the geometric form of the universe could be the ball and layer at the same time. 

The situation that we are observing in our galaxy or universe can compare with the next situation. We are sitting in the room in the house, that we have ever seen from outside. We are seeing other houses, we can push the walls of the room, and make conclusions about the house, where we are staying. 

We are seeing other houses, and because they are all looking at the same, we might think that the house, where we are is similar to others. We can see the roof of the gate corridor canopy, but that thing is a minimum part of the building itself. We cannot be sure if the building is similar to others if we are not seen it outside. 

There is the possibility that the house where we are living is looking different than others. So we must go out for making sure is the house we are living different looking than others. But even in that case, we can see things, that are visible from outside. We cannot see things like materials or tubes or other things from outside. 

()https://www.space.com/22395-elliptical-galaxies.html

()https://en.wikipedia.org/wiki/Milky_Way

()https://en.wikipedia.org/wiki/Shape_of_the_universe