So when Earth loses its gravity

Assume we reach a time in the future when Earth loses its gravitational pull on all matter on its surface and not tied down. Forget for a moment that life would have been extinguished in phases much before the end game of what is my question.

There will come a time when Earth with its weak gravity will not be able to hold on to it large bodies of water. When the water finally escapes into space, will it move as one big body of water or just a vast cloud of gas. Is there any such thing in space now which could be identified as having its origins bound within a land mass.

Well, this will never happen, so why bother speculating?

How does a planet lose it’s gravity?

The water will turn to vapor in the vacuum of space maybe. Can it survive in the form of ice? II don’t know what would make a cloud of vapor hold together if there’s no gravity. Is there still centrifugal force affecting it? Has gravitational atrophy affected the sun and other stellar objects? Are there any other forces in the universe still at play?

Given that when matter loses it’s gravity, water will also lose it’s wetness, does it matter?
CMC

If we ignore the curious idea that somehow gravity wears out, if we were to somehow take the Earth’s water and place it in space, it would have enough mass to hold itself together into a sphere. (It’s gravity has not worn out.) It would freeze over time. It still would have an atmosphere of water molecules, and if there were any fast moving streams of particles out with it (such as say the solar wind), they would slowly strip away these molecules, and the sphere would slowly dwindle to nothing. If it could get far enough away from the sun it would have a chance of surviving a very very long time as an ice ball. The Orrt Cloud is full of such objects.

Given that gravity doesn’t wear out, the final question makes no sense. The basic premise doesn’t happen, so no.

the Earth’s gravity comes from its mass. It’ll never lose it.

now AIUI the Earth could theoretically lose its magnetosphere if the core was to cool off and solidify. that would likely allow the solar wind to strip away the atmosphere.

Since your question supposes an impossibility, the answer is simply whatever you want it to be. When you start with a fairy tale premise, you get to make up your own conclusion. Gravity is a property of matter. It doesn’t wear out or get weaker.
If the Earth in your story magically loses gravity, does everything else lose gravity, too? That’s for your to decide. Does the water lose it’s gravity?
As for your follow up question, what do you mean by “having its origins bound within a land mass”?

Gravity is related to mass so no gravity means no mass. Someone smarter than me will have to tell us if the other basic forces would keep the earth together. My guess is they would not since they are very short range forces. The earth would spin itself into particles.

Is this magic happening only to the earth or the whole universe?

Is the purpose of the question to ask what happens to a large body of water in space? If so, the answer is that it will turn to vapour.

https://coolcosmos.ipac.caltech.edu/ask/244-What-would-happen-if-you-pour-water-into-space-#:~:text=Water%20poured%20into%20space%20

Here xkcd is a nice actual physics-based discussion of large blobs of wet stuff floating in space.

As to the OP: gibberish in, gibberish out.

" now AIUI the Earth could theoretically lose its magnetosphere if the core was to cool off and solidify. that would likely allow the solar wind to strip away the atmosphere."

That is assumed to be what happened to Mars, which smaller and has less gravity. It will happen to the earth one day, but I think we have more urgent things to worry about. The only way that the earth would have less gravity would be if it had less mass, which means losing big chunks of itself. It would be an interesting sight - from a safe distance.

The question may not really be GQ fodder…but it’s slightly more than just gibberish. It’s an Einsteinian thought-experiment, and can be addressed with some meaningful analysis…as has been done here.

Another one we see now and then is, what if the sun suddenly disappeared. The question is really about the “speed of gravity” and whether it would take eight minutes for earth’s orbit to go linear. The question can’t be meaningful, fully, because “suddenly disappearing” violates General Relativity’s equations. But it is still a question with a valid point behind it.

Does Earth still have a mantle of molten rock (under very high pressure from the weight of all the stuff on top of it—weight which would suddenly drop to nothing in this not at all plausible scenario) when this happens?

As Whack-a-Mole already noted, the earth would fly apart because there aren’t any forces strong enough to hold it together. Not only the pressure of the mantle and core, but centrifugal force from rotation, would cause the puppy to break into chunks, which would break into littler chunks… Maybe at some molecular level there would be some cohesion, but that’s more of a chemistry question.

Rocks would stay together and some other stuff as well, so the Earth won’t be reduced to molecules. Relatively small pieces, though.

Unless the negativity will pull us through, of course.

Sounds more like explode apart rather than fly apart.

That’s what I would expect. So much of the Earth is extremely hot metal under extraordinary pressure, the rest of it almost doesn’t matter but for the force of gravity keeping it all together. If gravity goes away, then the shell of the crust isn’t going to keep the planet together for long at all. Forget about flying apart, it’s “teh splodin’’” (my words) you’ve got to worry about.

The pressure by itself probably wouldn’t cause much of an explosion: While the lower layers of the planet are under tremendous pressure, it’s materials that don’t change their volume very much under pressure, and so there’s not much energy stored in that pressure.

The rotation, however, has plenty of energy, and would produce something distinguishable from an explosion only in that it would be almost entirely in one plane.

I’m sure that Roland Emmerich could come up with some representation of what it would look like.