Just to clarify, this isn't a fourth state, this just seems to be a different liquid phase. Water has a hugely complicated phase diagram -- there's fifteen phases of water ice known experimentally and a few more predicted in theory.

I haven't been able to find the original paper (damn you discovery.com) so let me know if you find it.

Couldn't find it either, but after looking around, it appears to me that the research discussed in the posted article is not so ground-breaking as the writer suggests (of course, it hardly ever is, y'know). Papers about liquid-liquid phase transitions in water go back a number of years.

For example, here is a paper from 1997 that speculates about such a phase transition.

http://iopscience.iop.org/0295-5075/42/2/161

And here is a recent paper about such a phase transition found in a computer model (which seems to be what the posted article is talking about). This paper is not by Kumar & Stanley, but it cites a number of papers of theirs.

http://arxiv.org/abs/1105.5295

Is this just an addition to the already-known 15 types of ice? http://en.wikipedia.org/wiki/Ice#Phases

Yes, except it's a new liquid phase rather than a new solid one.

As someone who did computational modeling of water, this strikes me as kind of odd. The "hello world" of computational molecular dynamics is simulating water in different phases, phase changes, etc. (including the different ices). I'm interested to hear more, but incredulous.

Can this kind of molecular dynamics simulation by done on a simple desktop machine? What system and software do you recommend if I want to experiment with simulation, starting with this "hello world" project? Do you recommend starting from scratch or using some specialized framework? (For context, I'm a professional programmer and mathematician by training.)

Why is water thought to have only 3 states? Is it impossible to transform water into a plasma state?

Water is a molecule, not an atom. There are no molecules in plasma since the electrons have all wandered off. So if you heat water gas enough, it becomes a plasma of hydrogen and oxygen.

You are almost 100% right. There are almost never any molecules in plasma: http://physics.aps.org/story/v22/st17

I don't know for certain, but I suspect in plasma situations it stops be H2O and becomes hydrogen and oxygen plasmas separately and can't really be considered water any more.

It should probably be expressed as a "sub-state".

  - Solid
    - However many states there are...
  - Liquid
    - Odd Liquid
  - Gas
  - Plasma?

Celsius please, or at least have both.This is supposed to be science not a localised weather report.

Better yet, Kelvin. I cringe when science-y things don't use that.

Perhaps, but given that we are discussing water, using Celsius seems a particularly appropriate choice.

Looks like people have known about many phases of water for ages: http://www.lsbu.ac.uk/water/phase.html

Oddly, it appears that Ice XIII and Ice X exist, but not Ice IX.

Look closer, Ice IX is on that phase diagram. Temperatures below 200K, and a very narrow pressure range just above I and XI.

> very narrow pressure range

On a logarithmic scale.

This article is EMPTY of details, and for someone actually interested in this new phase of water, I am severly annoyed.

I genuinely hope that "someone actually interested in this new phase of water" is on your business card, resume, or at least your Twitter profile.

4th state of water is a slushi... good observation scientists. good observation.

From the looks of the article, it seems like it's meant for people who are interested in popular science, but then the author uses degrees Fahrenheit everywhere.