If the moon creates the tides, why don’t any other objects get lifted by its gravitational pull?
In: Planetary Science
I got the actual answer right here!!
Tides are based on the difference of gravitational pull on opposite sides of the planet. The moon pulls water on the side of the earth closer to the moon MORE than the farside, which creates a bulges on opposite sides of the earth (high tide) with squeezed sections in between (low tide).
Why doesn’t the Sun create bigger tides than the moon, it’s gravity is bigger right? It’s because the key is not the strength of the pull, but in the change of that pull across the earth. This effect is more pronounced for closer objects (goes by R^3 rather than R^2 for those that care), so the moon dominates over the sun.
None of these forces are strong enough to overcome Earth’s pull and ‘lift’ things, but it can squeeze them.
Tides are not created because the moon’s gravity directly lifts the water. Instead, they are caused by the Earth’s rotation within the bulges of water created by the moon’s gravity. The combined gravitational effects of the moon and the sun create a bulge of water on the side of the Earth closest to the moon.
As the Earth rotates, it moves through these bulges, resulting in high and low tides in different regions as it spins on its axis.
So, tides are the result of the Earth’s rotation interacting with the bulges of water created by the moon’s and sun’s gravitational forces.
The moon pulls all objects equally. Just most things are not big enough or fluid enough to see it. The two we can “see” are atmospheric and oceanic tides.
The earth has 326 quintillion gallons of water on its surface. The moon is pulling on it all at the same time, and across all that water it only gets a few feet of movement towards the moon
All the other answers here are either missing a major component or are just flat out wrong. Most of the forces doing the actually raising of the tides aren’t lifting the tides directly away from the Earth. Draw a circle, that’s the Earth. Now draw the Moon off to the right (and remember that the moon is *very* far away. Draw lines from various points on the right side of the surface of the Earth to the moon. That represents the direction that the Moon is pulling the oceans towards. Now draw lines from those same points on the Earth, to the center of the Earth. That represents the direction that gravity is pulling the oceans. What you’ll notice is that for most of those points, the lines that you drew to the Moon don’t line up to form a straight line with the lines you drew to the center of the Earth. There is a bend. Imagine you are standing on one of those points. If there was no gravity, which direction would those lines to the Moon pull you relative to the surface of the Earth? Yes, away from the Earth, but also sideways along the surface of the Earth. Now these forces are very tiny. So the part of the force that is pulling away from the Earth doesn’t matter, but the part of the force that is pulling the oceans sideways along the surface of the Earth, doesn’t have anything (gravity) acting against it. Because the oceans are made of water, they flow in that direction, or towards the right side of the Earth.
https://science.nasa.gov/moon/tides/
Some interesting stuff. I knew about tidal lag between the moon, but I assumed the moon came before the high tide but the tide actually leads the moon <Head scratch>
In basic terms, the moon pulls fluids because they’re “easier” to pull.
In slightly more technical terms, the apparent influence of the moon’s gravity on oceans is because 1) oceans are literally massive, gravitational pull is based on mass and 2) oceans are fluid, so it’s easier to make them move around. It’s worth noting that this also happens with our atmosphere, just to a lesser extent cause our atmosphere isn’t quite as massive as our oceans. The moon still pulls on solids, it’s just less noticeable cause they aren’t fluid.
Because tides are caused by water being squeezed to the point under the moon (or on the other side of the Earth as the moon) not by the moon pulling up on the water.
Basically all the water all over the earth is being given a slight tug by the moon’s gravity, and the net effects of all these slight tugs, across the huge surface of the earth, is a movement up or down by a few feet.
Other objects would need to be planet sized, and fluid like water, to experience the same type of thing.
It’s actually quite complicated, and has a lot to do with momentum as the earth turns. It isn’t exactly caused the moons gravity as much as it is caused by spinning objects responding to changes at a right angle. Confused? Just know that it is way more complicated than just being lifted by the moons gravity.
There are a lot of inaccuracies in here.
Simple answer is; the Moon does not have the gravitational power to create tides, or more accurately if it was the only thing acting on the earth the tides would be very much smaller.
The sun is the main influence that causes tides, the moon just creates variations in the regulatory of those tides, making them higher or lower than normal.
Have none of you seen Moonfall? All this is explained in an entertaining and highly accurate movie. I especially like the bit where the car jumps a really big ravine because of the moon. Or when the protagonists try to run away from the moon (this was. 2022 $150m film from the director of Independence Day and The Day after Tomorrow).
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