Moon the one and only natural satellite of Earth is much more than just a heavenly body to gaze at, in the night sky. It helps direct our ocean currents and tides, the movement of Earth’s atmosphere and climate, and even the tilt of our planet’s axis.
So what would happen to Earth, and us, if it promptly disappeared without notice? Would we survive it? Sadly, probably not.
Life without Moon
The most noticeable change right away would be that night-time would be significantly darker. So travelling during night where there are no road lights would be quite dangerous. Also camping at night time without Moonlight would be no fun.
The moon’s sudden absence would also confuse animals. In a 2013 review in the Journal of Animal Ecology, researchers found animals that use vision as their primary mode of interacting with the world benefit (survival-wise) from the moon’s presence. That’s no big surprise, but it does have interesting implications for the question at hand. Many predators, like owls and lions, rely on the cover of darkness with just a bit of moonlight to hunt effectively. With no moon, they would have trouble finding food. Rodents, on the other hand, tend to hide more when the moonlight is strong. It’s easier for their predators to detect them. With no moon, they would thrive. “I think you’d see some shifts in which species are common and which species are rare in a system,” says the study’s lead author Laura Prugh, a wildlife ecologist at the University of Washington.
No more surfing
The next immediate difference would be the tides. Because the moon is so close to us, the pull of its gravity impacts our planet. It’s not as strong as the gravity that the Earth exerts upon the moon to hold it in orbit, but it’s enough to pull our oceans back and forth, a force we call “the tides.” Without the moon, tides would rise and fall at a much slower rate, about one third of their current fluctuation, says Matt Siegler, a research scientist at the NASA Jet Propulsion Laboratory, who works on the Lunar Reconnaissance Orbiter. The tides wouldn’t completely stop moving as the sun also has some gravitational pull on the oceans, too, but not nearly as much as the moon.
A missing moon could cause even more disruptive changes, although on a much longer time scale. Without the moon’s gravity holding the Earth in place, the tilt of our home planet’s axis would probably shift drastically over time. Earth could go from no tilt with virtually no seasons, to a drastic tilt with extreme seasonal weather changes and ice ages in just a few hundred thousand years, Siegler adds. He points to Mars as an example, with its extreme climate variations as the tilt of its axis changes dramatically. It has no large, stabilizing moon to stop it.
In future we can build a lunar base for launching rockets, but with no Moon this won’t be possible anymore. But thankfully there’s no information of an Asteroid colliding in to the Moon anytime soon. So just relax and appreciate the beauty of Moon.
Also don’t forget to check out our post on what would happen if the Sun disappeared.