<p>Likely your conclusion is true.</p>
<p>It's hard to look into the interiors and one only has data from some form of seismic, thermal and rotational measurements as well as lab data from dynamic measurments on the phase behaviour of the materials under high pressure and temperature as found in the interior (which is a quasi-static state).</p>
<p>However simulations like <a href="https://arxiv.org/pdf/2107.13728.pdf" rel="nofollow noreferrer">this from Gao et al</a> or <a href="https://arxiv.org/pdf/2011.12803.pdf" rel="nofollow noreferrer">Naumova et al</a> (and references therein) seem to suggest that highly silica- or generally ion-enriched water is found in Uranus' and Neptune's interior.</p>

CC BY-SA 4.0
2022-03-24T14:50:59.240Z
2022-03-24T14:58:36.213Z
2022-03-24T14:58:36.213Z
planetmaker
<p>I would think that the solubility of the various gases present would be critical to any phase diagram. To what extent turbulence will allow any phase separation may be pertinent. Often, actually getting ones hands dirty in a lab gives insights.</p>

CC BY-SA 4.0
2022-03-24T12:12:35.600Z
Did you try to answer the question? If so, you might want to extend it a bit. I am not sure, if I am getting you correctly.
Nilay Ghosh
CC BY-SA 4.0
2022-03-24T12:33:15.090Z
This does not provide an answer to the question. Once you have sufficient [reputation](https://astronomy.stackexchange.com/help/whats-reputation) you will be able to [comment on any post](https://astronomy.stackexchange.com/help/privileges/comment); instead, [provide answers that don't require clarification from the asker](https://meta.stackexchange.com/questions/214173/why-do-i-need-50-reputation-to-comment-what-can-i-do-instead). - [From Review](/review/late-answers/29173)
WarpPrime
CC BY-SA 4.0
2022-03-25T16:50:38.923Z
I think they made a valid point about solutes affecting the phase diagram (presumably favoring the liquid); it would be interesting to hear more detail along this line.
Mike Serfas
CC BY-SA 4.0
2022-03-24T06:45:06.623Z
2022-03-24T06:45:06.623Z
Moggsy8
<p>Like most planets, Uranus has a very cold outer atmosphere and a very hot core.  What we <em>see</em> is a very thick primary atmosphere with plenty of hydrogen.  Deeper in, we might suppose that water condenses in clouds at maybe 200 atm of pressure. (Above that it would be ice crystals)</p>
<p>By &quot;might suppose&quot;, I've used the <a href="https://commons.wikimedia.org/wiki/File:Tropospheric_profile_Uranus_new.svg" rel="nofollow noreferrer">dodgiest source conceivable</a> to plot the atmospheric conditions on a <a href="https://webhome.phy.duke.edu/%7Ehsg/363/table-images/water-phase-diagram.gif" rel="nofollow noreferrer">phase diagram</a> of water, shamelessly thefted from Duke here, whereby I mean I took a Wikipedia contributor's dotted blue line, &quot;an extrapolation of the <a href="https://ui.adsabs.harvard.edu/abs/1987JGR....9214987L" rel="nofollow noreferrer">1987 Lindal et al. data</a> (solid blue) using a constant lapse rate of 0.82 K/km.&quot;</p>
<p><a href="https://i.sstatic.net/Y026a.gif" rel="nofollow noreferrer"><img src="https://i.sstatic.net/Y026a.gif" alt="enter image description here" /></a></p>
<p>Given this impeccable data (or other data you might contribute!), it appears that the extrapolated atmospheric conditions of Uranus take a shot straight down the fairway toward a layer of liquid water.  <em>IF</em> it's there.  The <a href="https://www.universetoday.com/18855/uranus/" rel="nofollow noreferrer">usual treatment of the topic</a> says that there is an atmosphere over a layer of ices ... without many specifics, since after all nobody can see it.</p>
<p>But do we have any indication at all?  <strong>Is there a reason to say probably yes or probably no to the question of whether a probe dropped into Uranus would reach <a href="https://www.chem.purdue.edu/gchelp/liquids/critical.html" rel="nofollow noreferrer">374 °C (the critical temperature of water)</a> before it would reach a liquid (probably, in that case) surface of water?</strong></p>
<p>(Note: I recall seeing some simulation of the overall temperature issue before, but with a range of outcomes, and this question is prompted by <a href="https://www.centauri-dreams.org/2021/05/19/exploring-ice-giant-oceans/#comments" rel="nofollow noreferrer">this report</a> that MgO dissolves extensively into H<sub>2</sub>O in Uranus, potentially altering the internal heat distribution.</p>

CC BY-SA 4.0
2021-07-09T05:27:14.900Z
The last line might be true: Uranus-water is indeed magnesium heavy: https://news.asu.edu/20210517-deep-water-neptune-and-uranus-may-be-magnesium-rich
Nilay Ghosh
CC BY-SA 4.0
2021-05-19T21:47:29.780Z
Interesting question, welcome to Astronomy SE! I've adjusted your title to better match your question since some users just read titles and then start answering. Feel free to edit further.
uhoh
CC BY-SA 4.0
2021-05-20T19:54:54.583Z
You might want to check 1.) whether chemical equilibrium at those temperatures allows water to exist (oxygen might be soaked up by other molecules) and 2.) whether water is soluble in H/He mixtures at those temperatures ( see https://ui.adsabs.harvard.edu/abs/2012ApJ...745...54W/abstract).
AtmosphericPrisonEscape
CC BY-SA 4.0
2021-05-20T21:17:06.177Z
A well-posed question! I tried to see whether there is some literature on the topic, but I only found a 2010 called *[Interior Models of Uranus and Neptune](https://iopscience.iop.org/article/10.1088/0004-637X/726/1/15/meta)* going somewhat in the correct direction, maybe that's helpful for you.
B--rian
CC BY-SA 4.0
2021-05-20T21:22:48.877Z
@AtmosphericPrisonEscape Concerning your 2nd point about ice-mixtures of different substances: More than a decade ago, I attended a physics collquium talk by some specialist on strange ice phases (in the shown phase diagram, the red numbers are refering to different *water* ice phases). Sadly,  I do not recall the name of the speaker, but I remember that he mentioned the application of his research for ice planets. Maybe I can figure out more about the colloquium...
B--rian
CC BY-SA 4.0
2021-05-20T22:11:13.447Z
@B--rian: The works by Helled, Vazan and others on those topics continues until today, so you should easily find updates. With that 2010 articles you've posted when comparing their central densities and temperatures with those $\rho$ and T required for liquid water in the Wilson&Militzer article, we see that the central values barely scratch that area of phase space. So the answer to OP's question is 'probably no, even if Oxygen would remain in $H_2 O$'
AtmosphericPrisonEscape
<gas-giants><water><uranus>
Could there be liquid water on Uranus? Are there any indications that there might be?
Mike Serfas
# Could there be liquid water on Uranus? Are there any indications that there might be?

(Asked by: username_0 on 2021-05-19)

Like most planets, Uranus has a very cold outer atmosphere and a very hot core. What we *see* is a very thick primary atmosphere with plenty of hydrogen. Deeper in, we might suppose that water condenses in clouds at maybe 200 atm of pressure. (Above that it would be ice crystals)

By "might suppose", I've used the [dodgiest source conceivable](https://commons.wikimedia.org/wiki/File:Tropospheric_profile_Uranus_new.svg) to plot the atmospheric conditions on a [phase diagram](https://webhome.phy.duke.edu/%7Ehsg/363/table-images/water-phase-diagram.gif) of water, shamelessly thefted from Duke here, whereby I mean I took a Wikipedia contributor's dotted blue line, "an extrapolation of the [1987 Lindal et al. data](https://ui.adsabs.harvard.edu/abs/1987JGR....9214987L) (solid blue) using a constant lapse rate of 0.82 K/km."

[![enter image description here](https://i.sstatic.net/Y026a.gif)](https://i.sstatic.net/Y026a.gif)

Given this impeccable data (or other data you might contribute!), it appears that the extrapolated atmospheric conditions of Uranus take a shot straight down the fairway toward a layer of liquid water. *IF* it's there. The [usual treatment of the topic](https://www.universetoday.com/18855/uranus/) says that there is an atmosphere over a layer of ices ... without many specifics, since after all nobody can see it.

But do we have any indication at all? **Is there a reason to say probably yes or probably no to the question of whether a probe dropped into Uranus would reach [374 °C (the critical temperature of water)](https://www.chem.purdue.edu/gchelp/liquids/critical.html) before it would reach a liquid (probably, in that case) surface of water?**

(Note: I recall seeing some simulation of the overall temperature issue before, but with a range of outcomes, and this question is prompted by [this report](https://www.centauri-dreams.org/2021/05/19/exploring-ice-giant-oceans/#comments) that MgO dissolves extensively into H2O in Uranus, potentially altering the internal heat distribution.

**Tags:** gas-giants, water, uranus

> **Comments:**
> **username_2**: Interesting question, welcome to Astronomy SE! I've adjusted your title to better match your question since some users just read titles and then start answering. Feel free to edit further.  
> **username_3**: You might want to check 1.) whether chemical equilibrium at those temperatures allows water to exist (oxygen might be soaked up by other molecules) and 2.) whether water is soluble in H/He mixtures at those temperatures ( see https://ui.adsabs.harvard.edu/abs/2012ApJ...745...54W/abstract).  
> **username_4**: A well-posed question! I tried to see whether there is some literature on the topic, but I only found a 2010 called *[Interior Models of Uranus and Neptune](https://iopscience.iop.org/article/10.1088/0004-637X/726/1/15/meta)* going somewhat in the correct direction, maybe that's helpful for you.  
> **username_4**: @username_3 Concerning your 2nd point about ice-mixtures of different substances: More than a decade ago, I attended a physics collquium talk by some specialist on strange ice phases (in the shown phase diagram, the red numbers are refering to different *water* ice phases). Sadly,  I do not recall the name of the speaker, but I remember that he mentioned the application of his research for ice planets. Maybe I can figure out more about the colloquium...  
> **username_3**: @username_4: The works by Helled, Vazan and others on those topics continues until today, so you should easily find updates. With that 2010 articles you've posted when comparing their central densities and temperatures with those $\rho$ and T required for liquid water in the Wilson&Militzer article, we see that the central values barely scratch that area of phase space. So the answer to OP's question is 'probably no, even if Oxygen would remain in $H_2 O$'  
> **username_1**: The last line might be true: Uranus-water is indeed magnesium heavy: https://news.asu.edu/20210517-deep-water-neptune-and-uranus-may-be-magnesium-rich  

---

## 2 answers

### Answer by username_5 on 2022-03-24. Score: 2

Likely your conclusion is true.

It's hard to look into the interiors and one only has data from some form of seismic, thermal and rotational measurements as well as lab data from dynamic measurments on the phase behaviour of the materials under high pressure and temperature as found in the interior (which is a quasi-static state).

However simulations like [this from Gao et al](https://arxiv.org/pdf/2107.13728.pdf) or [Naumova et al](https://arxiv.org/pdf/2011.12803.pdf) (and references therein) seem to suggest that highly silica- or generally ion-enriched water is found in Uranus' and Neptune's interior.


---

### Answer by username_6 on 2022-03-24. Score: -1

I would think that the solubility of the various gases present would be critical to any phase diagram. To what extent turbulence will allow any phase separation may be pertinent. Often, actually getting ones hands dirty in a lab gives insights.

> **Comments:**
> **username_1**: Did you try to answer the question? If so, you might want to extend it a bit. I am not sure, if I am getting you correctly.  
> **username_7**: This does not provide an answer to the question. Once you have sufficient [reputation](https://astronomy.stackexchange.com/help/whats-reputation) you will be able to [comment on any post](https://astronomy.stackexchange.com/help/privileges/comment); instead, [provide answers that don't require clarification from the asker](https://meta.stackexchange.com/questions/214173/why-do-i-need-50-reputation-to-comment-what-can-i-do-instead). - [From Review](/review/late-answers/29173)  
> **username_0**: I think they made a valid point about solutes affecting the phase diagram (presumably favoring the liquid); it would be interesting to hear more detail along this line.  

---

