Here's What Would Happen If There Was No Gravity

Admit it: At some point, you've wondered about what the world would be like if humans weren't naturally grounded. Unlike many birds and insects, man wasn't born with the biological ability to defy gravity, the force that literally keeps our feet on the ground.

According to Live Science, gravity completes the quartet of the universe's four fundamental forces, together with strong nuclear forces, weak nuclear forces, and electromagnetism. Gravity is the force of attraction between two given objects. Everything in the universe that has mass — whether it's a coral reef, a spider, or a popular parody singer – attracts every other object with mass (via Universe Today). The strength of that attraction depends on how massive the objects are and how close or distant they are from each other. When people hear about gravity, planets usually come to mind, which is why it can be difficult to picture how it works on a smaller scale. That's probably also why this critical requirement for existence tends to get ignored.

But what if gravity stopped working one day? What if it disappeared, even for just ten seconds? Take note that based on physics, a scenario that suddenly eliminates gravity from Earth is impossible — which is extremely fortunate, because if that were to happen, these terrible, terrible things would certainly follow.

Fun fact: Humans have more than five senses. One of the most important ones — and one that we tend to take for granted — is our vestibular sense, which is what helps us tell up from down and prevents us from falling over. This internal sense of balance is what allows people to ride bikes, walk along a straight line, stand on one foot, or move their heads and limbs without getting disoriented.

Nature explains that all of this is made possible by the intricate system in every person's inner ear that keeps track of the body's movement, the different directions and how they relate to the person's current position, and other aspects that play a role in making sure the person doesn't become a disoriented, headache-plagued heap on the ground. And as you've probably guessed by now, gravity has a lot to do with it.

Admittedly, the balance-setting organs in the ear (the otoliths and semicircular canals) technically aren't necessary for a human being to survive. However, taking them away would bring tremendous suffering. Or, as Wired succinctly puts it: "Imagine a gently oscillating, nausea-inducing scene from which there is no escape. That's what it feels like when the organs of the inner ear malfunction."

Despite the endless hours scientists have devoted to studying it, there's still no conclusive answer as to exactly why humans need sleep to survive. What experts do know, however, is that gravity has a strong connection to sleep patterns and the quality of sleep a person gets — and without it, both of those would be greatly impaired.

As The Conversation reports, astronauts rarely get some decent shuteye when they're off-world. This is especially the case during long-term spaceflight, in which the astronauts are subjected to a long period of low gravity. Even the seemingly simple act of lying down becomes a Herculean feat for them because, well, how exactly do you lie down in a setting where there is no "up" or "down?" Their internal clocks, which affect their sleeping patterns, are thrown into disarray. Plus, because there's no gravity to hold them down while they try to sleep, tightly secured sleeping bags are a must. 

Additionally, even if you manage to fall asleep, it's unlikely that you'll get enough. A 2018 study concluded that since gravity affects the human body during a person's waking hours, it is partly responsible for sleep. The study also affirmed that gravity conditions Rapid Eye Movement (REM) sleep, aka the part when you dream. According to Biology Online, this is only achievable when a body is lying down properly. (Interestingly, this is true not just for humans but for horses and elephants, too.)

Of course, once everything starts rolling around after gravity gets turned off, they won't stay on Earth for very long. As the planet rotates, every rolling object you can imagine will start to float into space, no matter how large they are (via HowStuffWorks).

Think being inside a big building (such as your office or the mall) would save you from this fate? Think again. As this chaotic mess plays out, you'll find yourself rolling and then floating towards the ceiling. If you somehow manage to survive this (not to mention the deluge of heavy equipment, appliances, and furniture unceremoniously flying your way), you'll notice that the entire structure will be drifting away much faster over time. As Cornell Astronomy details, it (as well as everything else outside) would be floating away in a straight line at an accelerated pace, as it deviates from the planet's spinning path.

Oh, and if you think that only the things that are on Earth would be affected by all of this, you'd be incredibly wrong. It's the pull of their respective planets that keep satellites in orbit. In other words, when Earth's gravity says bye-bye, so will the Moon (via Futurism). With nothing to keep the planet's sole satellite spinning around it, the Moon will drift off into parts unknown.

Now, you might not consider the Earth's atmosphere as an object that would be affected by gravity's loss. For the purpose of this discussion, however, it absolutely counts, which is important, because this is where things go from worse to truly horrific.

Just like the Earth's many bodies of water, gravity is the only thing that's keeping the atmosphere, well, the atmosphere. In fact, the Moon's comparatively weak gravitational pull is why its extremely thin atmosphere is quite different from Earth's (via Forbes). According to the What If Show, as every object on the planet starts to tumble around, the molecules in the atmosphere would immediately begin to drift off into outer space. This, of course, includes oxygen, which not only keeps most living organisms alive.

If that doesn't already sound horrifying enough to you, Science ABC adds that with Earth's atmosphere disappearing, the air pressure would change quickly and significantly. If you've ever been on an airplane, you've probably experienced the ear-popping sensation that happens as your plane ascends. Now take that, but make it about a couple hundred times worse.

According to NASA, the Sun is so huge that more than a million Earths could fit in it. Due to its sheer size and massive gravitational force, this star, which sits at the center of the solar system, manages to keep Earth and other planets following specific orbits. And like our home planet, gravity is what keeps the Sun's burning-hot gases in its ball-like form. This is also the case for other stars. As for black holes, they're unbelievably massive, so much that even light is no match for their gravitational pull (via NASA).

If you were to expand this thought experiment and remove gravity not just from Earth but from the Sun and other celestial bodies, the results certainly wouldn't be pretty. As the BBC puts it: "Without the force of gravity to hold [the Sun] together, the intense pressures at its core would cause it to burst open in a titanic explosion. The same thing would happen to all the other stars in the Universe." Take note, though, that due to how distant the other stars are from Earth, it's unlikely that any Earthlings would be around to witness the celestial light show.

To get a proper grasp of how bad things could get if there were no gravity, each of its effects have to be discussed separately. However, if this unlikely situation ever came to pass on Earth, everything awful that would happen would occur simultaneously: Your body would malfunction, various objects would start tumbling and flying into outer space, the oceans and atmosphere would float away from the planet, and the planet itself would crumble like a cookie smashed with a hammer, all at the same time. Plus, the Moon's departure would likely cause some serious seismic activity while all of these things are happening, according to Seeker. It would be a miracle if anyone could survive these horrors for five minutes, especially since no one would be able to run, much less move. Oh, and you'd probably die sopping wet and drenched in your own sweat, because those beads of perspiration would pool all over your skin (via the What If Show).

There's still a lot that scientists don't completely understand about gravity, even though it's already clear that this force is critical for life on Earth to continue. Plants seem to be especially dependent on it, New Scientist states, based on experiments conducted both on Earth and in space. It's entertaining to ask, "What if there were no gravity on Earth?" — but it's truly fortunate that no one will ever know the answer through firsthand experience.