By Chris Apps
Do you remember playing the “why” game with the grown- ups of your life? Why is the sky blue? Why can’t I have a purple kitty? Why is uncle putting a “rug” on his head? Odds are, you are no longer this child-like inquisitor. But, in having assumed your new “all-knowing” role, you have likely learned an important lesson: sometimes you just don’t know, and sometimes the best answer is simply “Because that’s the way it is.”
This is especially true of space, which has recently been in the news quite a bit: astronaut Chris Hadfield is now aboard the International Space Station (ISS), and will soon be the first Canadian to assume command; the first Canadian in space, former astronaut Marc Garneau, is running for leadership of the Liberals; feasibility studies for asteroid mining are popping up with greater frequency; and just last week, SpaceX ’s privately operated Dragon Spacecraft completed its fifth payload delivery to ISS. As a space enthusiast, I’m losing my shit. But a big part of my appreciation for all this doesn’t come from our interactions with space, but rather space itself. What follows is my attempt to explain a few of the cooler mysteries and some bits of physics that make everything out of this world so incredible.
The Beginning: The Big Thing?
While scientists have been smart enough to avoid esoteric philosophical questions concerning why we and everything we know exists, nothing has stopped them from seeking out how. Unless you’ve been living under a rock, or confined to some weird religious compound, you’ve heard of the dominant theory: the Big Bang.
Prior to this cataclysmic event — about 15 billion years ago — there was not a whole lot going on in our universe. As far as we know, literally nothing existed. No chemicals, no minerals, no gas clouds, nada. Suddenly, the energy of a fiery explosion became the first thing to come into being. From this heat, space erupted, and from the explosion, everything was created.
The conditions for energy, matter, and even time itself had become tangible from a state of nothingness. If it’s difficult to wrap your mind around the notion that the forces and dimensions governing physics at one time were not there, you are not alone. In fact, if you can wrap your mind around that shit, you might be one of a kind. The creation of these forces, particularly gravity, led to the accumulation of atoms, which formed very dense clouds of gas called nebulae. These gave birth to stars, stars to planets, and so on.
Descriptions of this supposed explosion are vague, mainly because it’s all an assumption: we don’t know for sure there was nothing before the big bang, and it’s pretty hard to explain what exactly it was that became hot and dense enough to explode in the first place.
This has lead to a great deal of argument and a bunch of other theories including the possibility of another universe existing prior to ours. But I could argue that our existence can be chalked up to a unicorn fart, and no one could really prove otherwise.
There actually is some pretty solid evidence supporting the big bang theory. Through observing the light emitted from distant galaxies and quasars, Edwin Hubble found that their wavelengths were shifting to the red end of the light spectrum — “redshifting” — indicating they are receding from the Earth.
This would suggest the universe is continually expanding. A good analogy then, is to think of the universe as an ever-inflating balloon, with us inside. This would suggest a point of origin, and thus a theoretical location for a big bang to have occurred. Light and microwave emissions as well as the distribution of galaxies have also been found to provide corroborating evidence.
Even if you don’t want to dwell on the past, you might question the future. How far can it all expand, and how long will we be able to enjoy the ride? A more ridiculous and equally legitimate question is whether there is a threshold to our existence, and whether or not there is going to be anything beyond it. Maybe there are a thousand more universes with a thousand more yous and mes wondering the same questions.
Going the Distance: Space Time
I’m not brazen enough to assume I can explain or even understand all the intricacies of space-time, but I can certainly attempt to paint the picture. One may recall how Douglas Adams’ Hitchhikers Guide to the Galaxy describes the cosmos: “Space . . . is big. Really big. You just won’t believe how vastly, hugely, mind-bogglingly big it is.” With space being so big, how do we measure it? Mere kilometres are not enough; rather, we use the light year — the distance traveled by light in one year.
Alpha Centauri, one of Earth’s closest stars, is super far away. Like, over 40 trillion kilometres far away. So, traveling at a con- stant speed of 1079 million km/h, it takes that light 4.37 years to hit our eyeballs from when it is originally emitted. That’s the closest one! Even using the most advanced technology available, it would still take us five million years to get there.
Space is big, to the point that there is no real frame of reference. If you can fit four earths into the storm on Jupiter, there is no point in using planetary units to describe size on this scale. Light takes up to 100,000 years to travel across our galaxy; this is a spectacularly huge neighbourhood, and what’s more incredible is that there are billions and billions of galaxies.
I am not pretending to be some sort of expert here. I’m just a dude who is really stoked on space. It’s pretty damned cool, after all. I have often heard from people that thinking about this stuff makes them feel depressed or even a little scared.
While this might stem from the realization that we are less than fly shit on a star map, I have personally found deep comfort in this insignificance. When the universe is that big, the difference between your B+ and your A- seems pretty petty.
The next time you look up at night, think about how many years that bright blue dot has been traveling to reach you. Then consider this: since that light is a constant and was emitted sometime a hundred thousand years ago, you are effectively looking back through fucking time.
Our Home: The Planets
Sure, space is neat-o, but one could just as easily write about how simply awesome humanity is. We have grown up here, we have evolved here, and our recourse has been to spread about in hopes of finding enough room for all of us. But — and this is a pretty sizable “but” — this development didn’t start with some monkey, or even some ugly-ass fish that crawled out of a bubbling swamp. It started with our very platform, our growth medium: the planet.
Ever wondered how planets form? So have scientists, and those crazy bastards have come up with something called the nebular hypothesis. The process starts with a star being born. This happens in a nebulous cloud, which is pretty much a huge clump of hydrogen and carbon monoxide gases.
The matter in the cloud slowly combines into clumps, getting heavier and heavier. It gets so heavy that it begins to collapse, heating the hydrogen through the increase in pressure, and igniting the star. There is a boom, and the new star is left with a “proto-planetary disc” around it, which are essentially super-hot bands of water and hydrogen compounds. Up to this point, the process has taken
100 million years.
As they spin around the star, elements and minerals start to glob together, forming grains of dust that get bigger and bigger. Eventually, they become moon or mars-sized proto-planets. It is actually quite quick to reach this stage, only 100,000 to 300,000 years.
As the collisions continue, the velocities of the remaining objects become more equal. This equality ensures that further collisions are far less destructive, so when they get close to one another, they stick rather than smash together. This accretion process continues, and as their mass increases, their gravity forces them to be roughly spherical.
So when you get a surface, what happens next? How does life grow upon this platform? You think I have all day? Go watch Planet Earth. I’ll say this much, though: if you factor in the sheer size of space, the possible chemical concoctions that can occur in planetary formation, the distance from their parent star, and the fact that there is a nebulous cloud of gas way back in humanity’s family tree, you’ll find that we are not a virus.
While I hesitate to use the word at the risk of a religious connotation, there is no word more apt for describing what our planet and the development of humanity actually is: a miracle.
The Third Kind: Aliens
Sometimes facing up to the truth is just too much. The thing is, when it’s all on the line it’s easiest to block out our least favourite portions of reality in the hopes of creating some parochial hallucination we would like to think is a few steps from utopia.
But to be honest, before I started reading and learning about our universe, it was all too much to think about, and far easier to
scoff at those who tilted their heads towards the skies and chose to question everything.
You think you’ve got the argu- ments for ET on lockdown. I mean, Area 51 right? They have all those UFO sightings and crazy-intricate crop circles. Some German broad lived in the Peruvian desert studying the fuckin’ Nazca lines for over 30 years, thinking aliens had something to do with it; the Mayans had pyramids, the Egyptians had pyramids. Coincidence? Had to be aliens! What about all the
abductees?
There are mountains of details associated with those and other arguments, and many of them have enormous followings. But let’s not get too far ahead of ourselves; these arguments are not the cause for my change of heart — the odds are.
Modern telescopes can see 50 billion galaxies or so, but the uni- verse is way bigger than that so we’ll call it a moderate 100 billion. Each of those galaxies has at least 100 billion stars. So there at the very least are 10,000,000,000,000,000,000,000 stars kickin’ about. Even if we say that the chances of one planet or biting one of these stars is one in a million — and in fact, the odds are better than that — we can assume there are 10,000,000,000,000,000 planets in the universe. Call it a one in a million chance that those planets can support life: 10 billion planets with life.
The Drake equation was created with legitimate math and science to estimate the number of intelligent, communicating species in the galaxy, and the best values come in at around 10,000!
I doubt alien life will be in the form of a little green man. Right now my money is on bacteria, which isn’t so impressive. All those arguments about contact — the abductions, crop circles, and Mayan stuff — I just don’t see it as possible. The universe is simply too big.
So while I know that there are intelligent beings on some far off planet, I lament the fact that our planet will probably fizzle out and die before we get to meet them. Maybe we are more advanced than they are. Maybe they are viscous pulsating orbs of goo and humanity ended up being the best tail to be pinned on the cosmic donkey. We don’t know, but there is certainly life beyond Earth.
The Galactic Mystery Spot: Black Holes
Everyone has heard of black holes, whether as part of a sexual innuendo, or more appropriately as a bottomless pit that takes you somewhere else in space. But what are they, really? The fact is that we can only postulate. No one really knows, and it is fundamentally impossible to ascertain the truth. Astrophysicists can now, at least, agree that they’re real, but observable evidence has been harder to come by than the last cupcake at a fat-kid convention.
So, here’s the theoretical deal:
Think of space-time as a sheet being stretched out by you and three friends, a la the parachute game in elementary school, flat and tight like Jane Fonda’s abs in the 80s.
Now, toss a baseball on there and think of it as a planet. It sits in space-time, only slightly distorting the fabric. If you threw a golf ball on the blanket just so, it would roll around the conical indent created by the heavier mass. If you remove friction from the equation, it can basically revolve around the base- ball forever. This is what’s happen- ing with the Earth and its moon.
Throughout this scenario, light — our steady and unwavering pal – passes by with no problem. Paltry planets don’t exert a strong enough gravitational pull to distort its path. But now imagine placing a sewing needle in the sheet with an aircraft carrier tied to it underneath; imagine all that mass and ability to distort the fabric, concentrated on such a tiny point. That’s a black hole and it’s a big enough deal to keep even light from escaping.
There are a few ways black holes come to be, but for brevity’s sake I’ll give a shout out to gravitational collapse alone. As it goes in Hollywood, so it goes in space: all stars eventually burn out and die. They start out young, dimly flickering in the distance, barely noticeable to us. After they do their thing for a while, the explosive nuclear heat they generate keeps them burning. But all good things must come to an end, and like Courtney Cox, eventually there just isn’t enough fuel left to keep the fires burning bright.
The temperature drops and the star collapses under its own weight. When this happens to an enormous star a Courtney Cox- sized mega-giant — the collapse is particularly devastating; it cannot find equilibrium between the force supporting it and the gravity it creates, and it implodes. It falls inward, and all that is left behind is a singularity; the center of a black hole, where the regular laws of physics seem not to apply and Cougar Town is renewed for a second season.
A black hole then is an area in space that is so heavy and dense, that it can eventually pull everything into it. Since even light could not escape their grasp, they were dubbed black holes. They are iden- tified not by their emissions, but by the absence of light.
Don’t worry, though. Earth isn’t destined to be sucked into obliv- ion. We are outside the SZ, the Spaghettification Zone, scientifically known as the Schwarzschild Radius. So we’re good. The edge of that radius is the point of no return, named after an awesome Laurence Fishburne movie: it’s called the event horizon, and it has some cool properties.
There is a lot more to this that still needs explanation. If I’ve done my job right, you’ve been left with more questions than answers.
