The nice thing about the size of the observable universe is that it makes everything else, including big problems, feel much smaller in comparison. As science continues to probe deeper into the size and scope of the vast size of everything that surrounds humanity, new information about the Milky Way galaxy is also becoming more clear. For instance,a recent discovery revealed information to support the theory that the Milky Way has likely formed from the inside-out.
Now consider the size of Earth within the Milky Way galaxy and examine the image at the top of this post. By contrast, Earth is much smaller than the size of a marble. In fact, a marble is giving far too much credit when in fact, the planet would be smaller than a spec of dust in that picture. Now imagine an epic universal zoom out that goes back even further. The Milky Way shrinks and shrinks away until it becomes even tinier. By now, the Earth looks smaller than a minuscule little particle. And as for the people who are on it? Well, big problems don’t feel quite as overwhelming anymore.
Now that this concept has been demonstrated visually, how can it be signified numerically?
Consider that the size of the universe – and not just the observable one – is constantly expanding its size. This is standard science, known to humanity by the act of observing distant galaxies moving away from Earth through something called Hubble’s Law. A recent study estimates the Milky Way galaxy alone to have about 200 billion stars with roughly 40-50 billion of them having similar conditions to Earth’s sun. Based on these numbers, it’s further hypothesized that there are about 8.8 billion Earth-like planets with conditions that may be suitable for harboring life. These are commonly referred to as ‘Goldilocks planets’ because similar to the classic tale, they aren’t scalding, full of magma like Mercury or blasting high velocity winds like Neptune. They’re situated in conditions just like Earth.
Now couple this with the estimate that there are estimated to be a whopping 500 billion galaxies in the observable universe. Assume each of these galaxies is roughly similar to the Milky Way and multiply that number by 8.8. In simple terms, this could suggest 4.4 trillion Earth-like planets that could sustain life. For anyone who desperately wants to get off of this planet, that might not be such a stretch of the imagination after all.
Of course, given that technology is currently not in any state to take mere Earthlings to places that are so far, far away at this point in time, there’s a chance that this might still be a slightly unrealistic scenario. Still, with the size of the observable universe being as big as it really is, it does make problems feel much smaller when thought about in this context.
By Jonathan Holowka