What If the Moon Disappeared Tomorrow_done What If the Moon Disappeared Tomorrow?
Earth's moon plays a significant role in our culture, language and thoughts.
But does it … you know … matter? If it disappeared in the blink of an eye tomorrow, would we even notice? Would we even care?Well, it depends .
Do you like tides?
Gravity — at least the Newtonian kind — is pretty straightforward: The closer you are to something, the stronger its pull of gravity. So stuff that's closer tothe moon gets a stronger gravitational tug, and stuff that's farther away gets a weaker one.
When looking at the effects of the moon on the Earth, you can essentially boil it down to three parts: The Earth itself, the ocean-close-to-the-moon and the ocean-far-from-the-moon.On any given day, the ocean closest to the moon gets a bonus gravitational pull, so it rises up slightly, reaching out in watery embrace to what it can never reach.
And since the ocean is so big, all the water from one horizon pushes up against water from the other, resulting in a fantastic tidal bulge.Tide on one side of our planet, done. But what about the other? The solid rocky bits of the Earth are closer to the moon than the ocean on the far side, so the Earth too gets a little more snuggly with the moon, leaving the far-side ocean behind. Result? Tides on the far side. From the perspective of someone standing on Earth, it looks like that ocean is rising up, but really it just doesn't get to join the party. And there you have it: two tides on opposite sides of the Earth.If the moon disappeared, we wouldn't be totally out of tidal luck; the sun also stretches and squeezes the Earth, so our surfing opportunities wouldn't be completely eliminated.
Do you like 24 hours in a day?
The Earth used to spin on its axis faster than it does today.
After the hypothetical giant impact that led to the formation of the moon, the Earth's day was as short as 6 hours. How did it get to a leisurely 24?
It was the moon! The moon makes some pretty nice tides, but the Earth is also spinning on its axis. That spinning physically drags the tidal bulges around the planet. So instead of the tides appearing directly beneath the moon, they're slightly ahead of it, orbitally speaking.
So you've got a big lump of extra ocean water in a place where it's not supposed to be. Since gravity is a two-way street, that lump pulls on the moon. Like tugging a reluctant dog on a leash, that
tidal bulge yanks on the moon bit by bit, accelerating it into ever-higher orbits.
By the way, the moon is slowly getting farther away from Earth. And that energy to accelerate the moon has to come from somewhere, and that somewhere is the Earth itself: Day by day, millennium by millennium, the Earth slows down, converting its rotational energy into the moon's orbital energy.
If you took away the moon, itꞌs not like this process would reverse, but it wouldn't keep going. That might or might not be a good thing, depending on how much you like the length of your workday.
Do you like seasons?
The Earth's axis is tilted, and that tilt can change with time and it changes rapidly. What would happen if Antarctica pointed straight at the sun for 24 hours a day, plunging North America and Europe into permanent darkness?
And then a few hundred thousand years later it flipped over? We take thelong-term regularity of our seasons for granted, and we might have the moon to thank for it.
What might stabilize this is the moon: it's really, really big (at least compared with the Earth), and orbits us pretty fast. All that angular
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