It takes one of the most powerful lasers on the planet, but scientists have done it. They confirmed the existence of "superionic" warm ice – frozen water that can remain solid for thousands of degrees of heat.
This bizarre form of ice is possible due to enormous pressure, and the experimental findings may illuminate the internal structure of giant ice planets like Uranus and Neptune.
On the surface of the Earth, the boiling and freezing points vary only slightly – generally boils, when it's very hot, and freezing when it's cold. But both of these changes in the state are under pressure (because the hot water point is lower at higher altitudes).
In a vacuum of space, water can not exist in its liquid form. Immediately boils and evaporates even at -270 degrees Celsius – the average temperature of the universe – before desublimating in ice crystals.
But it is theorized that in extremely high pressure environments, the opposite happens: the water is solidified, even at extremely high temperatures. Scientists at the National Laboratory Lawrence Livermore directly followed this for the first time recently, explained in detail in a paper last year.
They created ice VII, which is a crystalline form of ice more than 30,000 times the atmospheric pressure of the Earth, or 3 gigapacals and destroyed it with lasers. The resulting ice had a conductive flow of ions, rather than electrons, which is why it is called supergone ice.
Now they confirmed it with the following experiments. They proposed that the new form be named Ice XVIII.
In the previous experiment, the team was able to observe general properties, such as energy and temperature; finer details of the internal structure remained elusive. Thus they designed an experiment using laser pulsations and X-ray diffraction to detect the crystal structure of the ice.
"We wanted to determine the atomic structure of the supernova water," said physicist Federica Koppari of LLNL.
"But, given the extreme conditions under which this predicted state of matter is predicted to be stable, the compression of water to such pressures and temperatures, and at the same time taking images of the atomic structure, was an extremely difficult task that requires an innovative experimental design."
Here's the design. First, a thin layer of water is placed between two anvil diamonds. Then six giant lasers are used to generate a series of shock waves with a progressive increase in intensity to compress water at pressures of up to 100-400 gigapacles, or 1 to 4 million times the atmospheric pressure on Earth.
At the same time, they produce temperatures between 1.650 and 2.760 degrees Celsius (the surface of the Sun is 5.505 degrees Celsius).
This experiment is designed so that water will freeze when compressed, but because temperature and temperature conditions could be maintained for only a fraction of a second, physicists were uncertain that the frozen crystals would form and grow.
So they used lasers to explode a small piece of iron foil with 16 additional impulses, creating a plasma wave that generated X-ray flash in exactly the exact time. These eyelashes diffractioned from the crystals inside, showing the compressed water really frozen and stable.
"The dimensions of the X-ray diffraction we measure are an unequivocal signature for dense ice crystals forming during ultra-speed shock-compression, indicating that the nucleation of solid ice from liquid water is fast enough to be observed in the nanoseconded time period of the experiment" , said Coppari.
These X-rays showed an ever-visible structure-cubic oxygen crystals at each angle, and an oxygen atom at the center of each person.
"Finding direct evidence of the existence of a crystal oxygen grid brings the last missing piece in the puzzle about the existence of supernova water ice," says physicist Marius Milo of LLNL.
"This gives extra strength to the evidence of the superior ice that we collected last year."
The result reveals an indication of how flying giants such as Neptune and Uranus can have such strange magnetic fields tilted with bizarre corners and equations that do not circle the planet.
Earlier, it was thought that these planets had a liquid ocean of ionic water and ammonia instead of mantle.
But the team's research suggests that these planets could have a solid mantle, like the Earth, but made from hot superionic ice, rather than hot rocks. Because supernova ice is highly conductive, this can affect the magnetic fields of the planets.
"Since the water of ice in the internal conditions of Uranus and Neptune has a crystal lattice, we argue that supernova ice should not flow like a fluid like the outer core of the liquid iron on Earth. Instead, it is probably better to see that superhemical ice would be moving similarly in a mantle on the Earth, made of solid rock, still flows and supports large convective movements of very long geological time frames, "said Milot.
"This can dramatically affect our understanding of the internal structure and evolution of the icebergs, as well as all their numerous extrasolar cousins."
The survey is published in Nature.