Reasons Why Space is Simultaneously Awesome and Terrifying

Why Space is Simultaneously Awesome and Terrifying
Go outside tonight and look up. Imagine you could go out there and look around. The reason you can't yet is because the coolest things about space are the same ones that make it so deadly.
Our entire existence takes place on one rather small planet, a pretty blue orb spinning and rotating around one rather small, not-very-impressive star. It's easy to forget that we are only a tiny, infinitesimal fraction of what's going on in the universe - partly a product of the universal human trait of bloated self-importance, but mostly because we just don't do much anywhere but here.

We have explored the area of space immediately surrounding our planet, we've sent probes ahead with no promise of a human-staffed follow-up mission in the near future, and we have some cool telescopes that can "see" really far away, but only in a non-particular kind of way. No, space is mostly a mystery to us. Which is a shame, because it's an incredibly awesome place. Unfortunately, it's also a very dangerous place to go hurtling into, because of what makes it awesome is also what makes it downright terrifying.
Our Minds Can't Comprehend the Size
You know space is big, but it's likely you haven't quite comprehended how big. Understandable, because the human mind simply is not equipped to deal with such vast distances - nothing in our collective history has given us anything we could compare it to. When someone tells you something is far away, you might think of a cross-country road trip or a transatlantic flight. But you're not even close.
Imagine you could drive space in your car. Cruising along at 65 mph, it would take you over five months to reach the moon - and the moon is our closest neighbor. We've actually been there. It would take you over 85 years to reach Mars, and over 6200 years to reach Pluto. If you felt like driving over to Alpha Centauri, our neighboring star, it would take 44 million years. The center of our galaxy? 309 billion years. The Earth itself is only a little over 4 billion years old. If you were to drive to the furthest reaches of the universe (that we know of), it would take you 142 million or billion years. Get comfortable.
The Laws of Physics Don't Always Apply
Astronaut In Space
On Earth, there are a few basic things you can count on, always, no matter what. Gravity. The laws of physics. But in space, gravity is what forms planetary systems and regulates orbits and such. It won't do squat for you as a space traveler.
If you lose your tether during a space walk, you can expect to continue moving in a straight line until you run into something. And given the distances we just discussed, it would be awhile. Right there, the laws of physics would help illustrate the concept of eternity/infinity.
The laws of physics govern most things in space about as predictably as they govern life on Earth, with one notable exception - black holes. The gravitational pull of a black hole is strong enough that even light can't escape (that's why they're black) - right there, physics is working. But when you come to the event horizon of a black hole, physics begins to break down.
In fact, if you were to mathematically calculate the existence and mechanics of a black hole using the laws of physics as we understand them, your answer would tell you that black holes can't possibly exist. But they clearly do. The problem is that they are so super-dense, they actually bend time and space. When you start bending time and space, the laws of physics throw their hands up and walk away in a huff. The fact that matter cannot be created or destroyed is a big deal in physics, and is the basic assumption of physics calculations - but when stuff gets sucked into a black hole, where does the matter go? We don't know. Wormhole? Maybe. Again, we don't know.
For a big brain-spinner, how about this: leading theoretical physicist Leonard Susskind has a theory about event horizons. He thinks that if you were to watch someone get pulled into a black hole, what you see and what that person experience would be two different things. You would forever see that person hover on the edge of the event horizon, even though that person was sucked inside years ago. Because both time and space are bent, you see. And this isn't a crackpot theory off the top of his head - Susskind can back all this up with Math.
You Can't See Most of It
Planets and stars in Space
Space is absolutely full of stuff, as far apart as it may be. Just look up at night and you can see stars, a couple of planets, and the galaxy itself if it's dark enough. If you go to NASA's website and look at some deep space telescope images, you can see thousands of planetary systems, asteroids, stars, nebula, and all the various dust and debris that make up our universe. But wait - you can't really see most of it.
Telescope scientist
Those beautiful images you see, taken from Hubble or another major 'scope are not what you would see in space, they're "enhanced" photos. See, most of what goes on in space involves invisible forces like radiation, gravity, magnetism, gasses, etc. So the telescope scientists assign colors to each invisible force they encounter out there, and sort of color-code the images. This allows them to see what's happening in each picture without having to refer to endless data readings every time. It also creates gorgeous desktop wallpaper, but it's not what you would see if you were actually there. You could be driving in your space car and pass right through a deadly radiation cloud without even knowing it.
But there's more. All the stuff we just talked about only makes up about 4% of the universe. The rest of the matter in the universe - about 23% of what's out there - is invisible to the human eye and to instruments. How do we know it's there? The Math says it is. But danged if we know what it is. We call it "dark matter". And there's a force called "dark energy" that comprises about 73% of the universe. We don't know what that is either, but we think it will ultimately destroy all matter everywhere.
So now you have something to think about next time you're stargazing.