We covered these questions in my Astronomy course so let me explain some of them.
For example what is Dark Matter, why does it make up 90% of our universe and seemingly not exist?
You're confusing dark matter with dark energy. This graphic should explain it.
Dark matter makes up around 20% of the stuff in the observable universe, and about 84% of the matter in the observable universe.
We know this because we can measure the dark matter in the universe. It's not that it "seemingly doesn't exist," it definitely does exist and we can measure it.
As an example of the original way that this dark matter was discovered, let's take a look at the orbits of stars around the centre of a galaxy.
As newton and einstein would predict, the orbiting speed of stars would go down the further you get from the centre of the galaxy.
But...
What we see is that the orbital speed is approximately the same, no matter how far away you are from the centre of the galaxy, and it holds true in every single galaxy that we can see!
And you might be inclined to say "Well maybe there's a reason that isn't extra matter floating around somewhere" and that might be a valid point if it weren't for the fact that even if you go
outside of the visible galaxy, your orbital speed continues to stay the same, or even
increase a bit as you get further out. Remember, gravity goes down with the square of the distance, so your orbiting speed should go down dramatically when you exit the galaxy, but that's not what happens.
You can see how the actual orbital speed goes as distance increases (solid line) and what we would predict it would be based on the visible mass. (dotted line)
So clearly, there's some sort of mass that is affecting this that we just can't see. That's what the dark matter is.
How can our universe keep expanding?
The best explanation for this to date is that space has an inherit energy to it, an energy that exists even in a total vacuum that is causing space to expand. As space expands more and more, this energy stays constant to an observer like a human because it's an inherit property of space itself. And because now there's "more" space, that means that there's "more" energy, causing it to expand even faster and accelerate. It doesn't expand
into anything else by the way, it expands into itself. Space can do that, it isn't required to have an edge in the classical sense.
This diagram should explain it:
Since energy can technically be considered "stuff," it's included in the count of the first diagram, which is why it has such a large percentage. It's
everywhere after all.
How does the universe just suddenly appear from nothing?
The question "What was before the universe" doesn't make any sense in this context. Because in this question you asked you've implicitly answered it, you said there was "nothing." But not only is "nothing" not well defined (We only have an in-universe idea of what "nothing" is) but it's not possible to know what was before the universe. Anyone who claims otherwise is just lying to themselves. For all we know, the universe is all there ever was, and it just is. There's no problem with that.
Why is it that every time we try exploring space to discover the truth the universe keeps getting bigger.
What do you mean by this? The universe is always getting bigger. If your implication is that space expanding is keeping us from finding "the truth" then you're incorrect, it's done no such thing.
What's up with the giant space roar?
Quite similar to the Wow! signal. Instrumental errors increased the intensity of what was detected, but we haven't figured out the exact cause of the transmission. No, it's not aliens.
What the forget is pulling our entire milky way galaxy, something is dragging our galaxy in like a tractor beam.
Nothing is pulling our galaxy.
It's basically like one big giant skybox in a videogame that doesn't get bigger nor smaller whenever you move closer and closer to it. Space just seems artificial, not real. Like it's being auto generated the more and more we look into it.
You're jumping to conclusions here. The reason the observable universe changes when you move closer to the edge is because the space was there the entire time, we just couldn't see it because the light hadn't had time to reach us yet. The universe is only 14 billion or so years old, so we can only see light that has traveled a maximum of 14 billion years to reach us. Any more than that hasn't reached us yet. If we "teleported" to the edge of the observable universe, we would see out another 14 billion light years because then the light
has had time to reach up to there. It's your own observable universe with the exact same radius as our own.
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