What Would Happen If The Moon Never Existed? | Unveiled

<h4>

What if the Moon Never Existed?</h4>

For 4.5 billion years, the Moon has orbited Earth, watching over us from more than 200,000 miles away. It’s an integral part of Earth’s culture and the mythologies of humankind, as well as providing motivation for early space exploration and affecting our environment in vital ways. But did it always have to be like this? And what would happen if the moon wasn’t there? 

This is Unveiled, and today we’re answering the extraordinary question; what if the Moon never existed?

Even now, we still don’t know for sure how the Moon was formed. The most common and credible theory is the “giant-impact hypothesis”, which says that another planetary body about the size of Mars impacted with the proto-Earth more than 4.5 billion years ago - at a time when the solar system was still forming. It’s then said that debris from that impact eventually reformed into the object we know as the Moon today. Because we don’t yet have time machines we can’t yet see exactly what happened in the ancient past… but most of the evidence to support the Giant Impact Hypothesis is centered on the Moon’s chemical makeup. It’s so seemingly similar to Earth’s, that it just makes sense for it and Earth to have once been cut from the same thing. Although, on the other hand, there’s a counter argument that the Moon and Earth are actually TOO similar to allow for the impact scenario, at all - with some arguing that there’s no (or little) evidence for the accompanying Mars-sized body that’s so key for that particular theory. 

There are, then, some other theories as to the lunar origin, including that perhaps Earth suffered multiple impacts, and the debris coalesced over time into the Moon… or that the material that formed the Moon was actually generated following another, separate planetary collision in the solar system, one which created both the Moon and the Earth, all at once. So, to some degree, the mystery remains, which all contributes to the overall enigma that surrounds our closest, largest satellite. Of course, moons, in general, are very common in space, although they’re not usually so massive relative to the body they’re orbiting. Ganymede - which is the largest moon of Jupiter, and in the whole solar system - still only has twice as much mass as Earth’s Moon does. Earth is seriously tiny compared to Jupiter, but our moon is only half of Ganymede. The size ratio is unusual between us and it.

It’s also reasonably unusual that we should have the moon, at all. While moons are common with the outer planets of our system - Jupiter, Saturn, Uranus and Neptune - they’re much rarer on this side of the asteroid belt. Of all the inner rockies, only Mars has moons to speak of; two of them, Phobos and Deimos, but they’re both very small. Phobos is the biggest with a diameter of just fourteen miles; the Moon, by comparison, is more than 2,100 miles across. Another major point of difference, Mars’ moons are also not in a completely stable orbit. As a result, Phobos is set to crash into the Red Planet in about 50 million years’ time, while Deimos is going in the opposite direction, and will one day leave Mars’s orbit entirely. Again, this is in contrast to Earth’s Moon, which is much more steady and reliable. Although we’ve grown so used to it just being there, it’s actually a truly unusual and uniquely balanced setup that we’re a part of.

With that in mind, perhaps there’s a parallel universe out there, somewhere, where the mechanisms to create the Moon (whatever they were) didn’t come about. Maybe there’s another world where the Giant Impact Hypothesis simply never happened? If Earth somehow had never had a moon in the first place, then how different would our world be?

To start, there would be a new brightest object in the night sky. Currently, this is the moon, reflecting sunlight to keep Earth illuminated even in the middle of the night. In a moonless reality, though, Venus would take that distinction. But unlike the moon, Venus isn’t always visible to us here on Earth. Sometimes it’s on the opposite side of the sun, and it’s always much further away. Even when Venus is visible, it’s clearly never as large or bright, by comparison. So, without the moon, there’d be far, far less natural light during nighttime hours - a change that would not only impact the lives of humans, but of the entire natural world.

Darker nights would still probably be the least of our worries, however, because the Moon is also integral to Earth’s tides. The tides are what move the ocean around our planet, circulating all the water and shaping valuable processes for the lives of sea creatures. Without the Moon exerting force, the tides would be much more stagnant. The motion of Earth and the gravity of the Sun would still create some movement… but tides would be about two-thirds smaller than they are right now, if lacking the Moon as a major influence. We’d feel the effects on land, as well, mostly through changes in weather. In some cases, this could be a good thing - storm swells might be slightly smaller, for example - leading to some previously massive weather events being a little more manageable. However, as we’ve come to rely so heavily on warm and cold fronts driven around the world on the tides, if the moon never existed then we’d never have had those… seasons will’ve developed differently, or never had developed at all… and that would’ve had knock on effects for farming, agriculture, the foods we eat, the lives we lead. 

More specifically, the lack of moon would have an especially huge impact on coastal ecosystems. Because without tides, the conditions for these wouldn’t really exist. There’d be changes everywhere. Perhaps crustaceans, for example, which populate along the coast, would all be much smaller than they are today, and at an earlier stage in their evolution. And without crustaceans (as they are) large parts of the food chain collapse. The fish that eat them go hungry; whatever eats the fish (including large predators like sharks, and us) also go without. Ultimately, without the moon, the oceans would be much less diverse and not as friendly to life. The moon may be miles above us, but it’s still key to what happens down here. More broadly, it’s thought that most animals on Earth right now (period) evolved from fish nearly 400 million years ago. In one model, essentially every living animal with four legs, every tetrapod, can be traced back to one particular four-legged fish. So, if the Moon had never existed, would that have stopped evolution, in general,  in its tracks? It’s arguably possible, although it’s impossible to say for sure. Would modern Earth then hold no life at all, like the rest of the planets in the solar system? Would it only hold simple, microbial organisms, incapable of developing into the complex life we have now? How far do you think the repercussions could spread? Let us know in the comments!

But, finally, let’s say that humans, at least, do still evolve into our current form. The lack of ocean diversity without a moon would certainly have stopped us from developing such rich seafood cultures. We likely wouldn’t have built many of the many coastal communities that exist on Earth today. Harbor towns and port cities might never have emerged as such key locations for the global economy. Beyond the impact on the sea, never having a moon would also affect our culture in other ways, such as in our mythology and folklore. The Moon is a key part in many pagan religions; in Greek mythology; in many ancient and contemporary calendar systems that rely on the lunar month. This Moon-less dimension, then, would mean wholesale changes in the stories and legends we tell ourselves; the religions we follow; even the days of the week that provide us with structure. From our metaphysical beliefs to our day-to-day timekeeping, the moon has a hand to play.

And, of course, in space travel; without the moon, where would we be? Our next-closest even vaguely achievable planetary body would generally be Mars... but it’s so far away that we still haven’t sent humans there. And, according to the more pessimistic outlooks, we may never manage to do so. Obviously the Space Race to reach the Moon, in the latter half of the twentieth century, could never have happened had the Moon not been there. So, would we just have attached our ambition to some other celestial object? Or, without the moon, might humankind’s interest in space never have flourished, at all?

What’s your verdict? Would humanity still have thrived without the Moon watching over it? Or, would the environmental and social impact of a hypothetical world without the Moon just be too much for us to withstand? In truth, take the moon out of history and there perhaps aren’t any overly explosive apocalypse scenarios that immediately take place. This isn’t quite the end of the world in an instant. But, if it had never been there, then that really could have changed humanity’s very evolution, from a biological, cultural, and even astrophysical point of view. And that’s what would happen if the Moon had never existed.