Liquid Planets

[Cheif Operations Director]

Could a planet that is just pure liquid exist (excluding the atmosphere)

[Bill Phil]

Probably not just liquid. Unless we stretch our definition.

Even gas giants are mostly fluid that's beyond the critical point. Neither gas nor liquid...

[cubinator]

There are water worlds made of mostly water in other star systems. They are usually larger than Earth. When you have an ocean compressed so much, the water turns into an exotic form of ice a thousand or so kilometers down, similarly to how hydrogen becomes a metal inside of gas giants. You might be able to get a smaller, moon-sized glob of water out of some sort of grazing impact, which might not have enough pressure in the core to turn into ice. It would likely boil away too fast to collapse gravitationally, though.

[Cheif Operations Director]

If you had a moon like shape or pure H20 and then "pumped" nitrogen has over it to create an atmosphere and then oxygen etc etc would it be able to be a pure water planet

[cubinator]

40 minutes ago, Cheif Operations Director said:

If you had a moon like shape or pure H20 and then "pumped" nitrogen has over it to create an atmosphere and then oxygen etc etc would it be able to be a pure water planet

It might be possible to do this artificially with a lot of energy spent making the pure water sphere. Maybe if you put a lot of ice together and then melted it you could get a water world. 

[kerbiloid]

You can just electrolize the water if you don't need exactly nitrogen.
Hidrogen will went out, and there is nothing to burn in oxygen except water which won't.

(Or wait until UV will do the same. But then you have a risk that oxygen will be venting out faster than UV makes it.)

Edited July 23, 2018 by kerbiloid

[magnemoe]

7 hours ago, kerbiloid said:

You can just electrolize the water if you don't need exactly nitrogen.
Hidrogen will went out, and there is nothing to burn in oxygen except water which won't.

(Or wait until UV will do the same. But then you have a risk that oxygen will be venting out faster than UV makes it.)

Yes, note that water wapor could also work as an atmosphere. 
The problem is that with an too small body you can not hold on to the atmosphere ant the water will boil away. With large enough bodies you get an ice core. 

Now you can get an smaller body perhaps as large as Ceres with an pretty think ice surface and all liquid inside if it get tidal heated if you put it with other moons around an planet. 

Two much water on an body would be bad, an waterworld say an 400 km deep ocean and you will get hundreds of kilometer with ice on the bottom and not much minerals so low chance for life. 

[KerikBalm]

Sure its possible... Melt mercury... liquid planet... liquid rock, but liquid none the less.

It was probably like that when it first formed, and it will be like that again as the sun nears the end of its lifespan.

If the pressure at the core keeps it solid... well... then lets move on to dwarf planets... like ceres...

[Vanamonde]

It depends on the size of the object. After a certain point, the pressure from the matter above would crush any substance into a solid mass, or one of those weird forms of matter, or even make it start fusing, in which case you no longer have a planet and instead have created a star. 

[Nuke]

i think a pure water world would still attract a sizable amount of space debris such that you would build up a lot of rocky debris over the course of millions of years. the end result is a rocky core. 

[NSEP]

4 hours ago, Vanamonde said:

It depends on the size of the object. After a certain point, the pressure from the matter above would crush any substance into a solid mass, or one of those weird forms of matter, or even make it start fusing, in which case you no longer have a planet and instead have created a star. 

This^^

Another thing to note is that water can't exist as a liquid in the vacuum of space, kind of like dry ice here on Earth. it will either become solid or vaporize.

In order to create water world, you first need make a giant lump of ice, create an atmosphere around it, and them melt the ice, in order to not make it vapourize. And even then, the pressure of the water, will make a core made of ice.

In theory, you can create a planet made of mostly of liquid water, but never 100% liquid.

[Cheif Operations Director]

On 7/24/2018 at 5:27 PM, NSEP said:

This^^

Another thing to note is that water can't exist as a liquid in the vacuum of space, kind of like dry ice here on Earth. it will either become solid or vaporize.

In order to create water world, you first need make a giant lump of ice, create an atmosphere around it, and them melt the ice, in order to not make it vapourize. And even then, the pressure of the water, will make a core made of ice.

In theory, you can create a planet made of mostly of liquid water, but never 100% liquid.

The pressure would also create friction which would heat it up. A water and ice tectonic plate... interesting