Zero Horizon - Episode 1

By Stella Evenstar

We believe that we know a lot about space and the universe, yet nobody is foolish enough (I hope not at least) to say that we know it all. It’s a strange thing that we debatably know more about space than we do about the oceans of our own planet Earth. It really depends on how you approach that statement. We’ll delve into the depths in another article, but we are here to talk about the universe that lies beyond our mother planet, Gaia, Terra, Mother Earth, Pachamama, Hou Tu, or whoever else you might name this great planet that gives us life, along with her family, such as the Moon, Luna, and the Sun, Sol. The observable universe can be perceived to a radius of about 46.5 billion light-years away, and it is estimated to be around 13.8 billion years old! While there is a lot of great science to support this, what do we really know? It seems like we’re discovering something new everyday. The Greek philosopher Socrates once stated, most aptly and humbly, “all I know is that I know nothing.”

To get started, we’re not going to get into detailed math and physics. Rather, We’d like to talk about some really cool and interesting things out there in the vast and endless black, shrouded in silence, and carpeted by unimaginable eons of cosmic brush strokes and points of brilliant diamond light . Now, read this and remember that you are on a sphere of rock, magma, water, and gas that is traveling around the Sun at 30km/s, and our galaxy (The Milky Way) is traveling through the universe at 2.1 million km/h. Note that galactic speed is very complex because the universe is always expanding and it matters what frame of refence you are using to determine that speed. Perhaps the best way to judge the “speed” of The Milky Way moving through the galaxy is by comparing it to the surrounding Cosmic Microwave Background. Don’t worry about that right now. We’re only getting started. We are literally living on a gigantic spaceship that is speeding through space at unimaginable speeds! But you don’t even feel that, do you?

I researched some of the most web-searched topics about astrophysics, and came up with a lot of good ones. But that’s no surprise. The universe has an endless array of interesting topics. We’ve got black holes, supernovae, dark matter, worm holes (research in progress), galactic collisions (Andromeda and The Milky Way will collide some day), gravitational waves, etc. ad nauseum. So, the trouble is, where to start?

I’m going to start with a more general look at all of this and get into more detail in future articles. Let’s start with some cool facts, or at least as close to the facts as we believe right now and seem to hold up under scrutiny. What is space?

What is space? Well, space and time are actually very interconnected. Sure, you look up at night and you see the moon and the stars, the galaxies, and that is space. It is also the void between all of that. But even the void is not truly a void. There is actually a very tiny, almost imperceivable, amount of matter, energy, and forces that we may not fully understand or maybe aren’t even aware of out there in the black vacuum. You have the matter we can perceive directly, the dark matter, which we cannot see directly and observe it through its gravitational influence instead, the energy and forces that we understand through rigorous scientific studies and observation, and the enigmatic energy and forces that we are still trying to understand. There is actually stuff there, just so little of it that you might as well imagine yourself in a canoe, in the middle of the Pacific ocean, with no land in sight, and not a single thing floating on the surface. Nothing around you. Alone. When you are out there in the black, you are alone. But not us back here on Earth! Because we are sharing this really amazing spaceship called Earth together! Can we please pick up our trash, by the way, and stop farting so much, because the ecosystem doesn’t seem to appreciate it?

Oh yes, I mentioned that space and time are connected. Well, I don’t think that I need to define time for anybody who is reading this article. However, time is a perception, sort of. It actually changes depending on certain characteristics of space and the perceiver! Space and time are intimately connected. Time is real, but it might be considered a perception if that helps you understand the rest of this article better. Whatever works.

This may be weird at first, if you’ve never heard it, but gravity and acceleration have a lot in common, and they both affect time. Einstein stated that "The effects of gravity are locally indistinguishable from the effects of an accelerating frame of reference." What the heck does that mean and what does it have to do with time?

There is a time difference that occurs in something commonly called The Twin Paradox. If there are 2 twins and one of them goes into space while the other stays on Earth, the twin in space will actually age less, comparatively. Both of them experience time in the same way, and their watches will keep count, but when the space twin gets home, their watch will be behind. What?

Time and space are interconnected. The astronaut twin was traveling at a high rate of acceleration. The faster you accelerate, the slower your time is compared to people or objects that are not accelerating. I get it, this is weird. In essence, the faster you travel, the more the world around you speeds up, or, more accurately, time passes more slowly for the twin experiencing greater acceleration or gravity. Even stranger, gravity is basically a form of acceleration. It isn’t really acceleration in the same sense, but it acts similarly, and it also affects time. Gravity is not really acceleration in the Newtonian sense (Important physics pioneer. Look into him.), but it is more or less equivalent to acceleration in terms of its local effects on spacetime.

If we change up the scenario and the space twin gets up there and then just stops moving, not orbiting the planet, just out there far enough that gravity is of no concern, and they cut the engines, then the “time dilation”, as it is called” will be different. If that spaceship and the Earth are both orbiting the Sun (Sol) at the same speed, then the effect would be reversed. This is because both the spaceship and Earth (Gaia) are orbiting (a form of acceleration) around the Sun at the same speed. Why wouldn’t the clocks match up then?

They wouldn’t match because of Earth’s gravity. Gravity is also a form of acceleration. I know that I might be spilling out too much at once, but this is really exciting, and it will lead to many more questions and many more articles. Anyway, since the spaceship and Earth are traveling at the same speed around the Sun, the addition of Earth’s gravity will now reverse the game, making the time for the Earth twin move slower in comparison to the space twin.

OK. That’s a lot to take in for 1 article. I also used a lot of colloquialisms interspersed with scientific words, so, take this as an intro and please do your own research into anything that sparked your curiosity. Afterall, that’s our job here, to ignite curiosity. We’ll pick this up again soon. I hope that you enjoyed it and that your mind was blown, metaphorically, not like a supernova.