The anomaly of water: ice

Unlike the vast majority of substances, ice floats in water liquids. That's because this is no more dense when you're at 0 ° C, but at 4 ° C. If not, there would be no icebergs or resale pipes to get frost. In addition, rivers and lakes begin to freeze the fund to the surface-and we could not skate on them.

It is not the only peculiarity of ice. In fact, there are 14 different varieties, something equally special because solids usually show two or three different types of crystalline structures.

The fact that we all know has a hexagonal structure and is called Ice Ih, but playing with the pressure and temperature can generate other structures.
In nature we also find ice or cubic lc, which is formed from water vapor at normal atmospheric pressure, but at temperatures below 80 ° C below zero. This kind of ice may form in the upper atmosphere.

In 1900, physicist Gus-tav Tammann discovered that the ice if subjected to 3,500 atmospheres-three and a half times the pressure that exists at the bottom of the Mariana Trench-appeared two new states: ice II and III.
A decade later, Percy Bridgman, from Harvard University, identified 5 more varieties. Among them, ice VI was known as "hot ice" since remained without melted to 80 C, provided that they exercise over the 6,500 atmospheres.

Of these, the most ghostly is the ice IV, whose structure was not discovered until 1981, 44 years after being detected, because it becomes very quickly into a more stable, V. And the race continues in 2006, Science magazine reported obtaining ice XIV.

In the solitude of the only space we have found that ice is amorphous. How do you get it? Well, ice cream artisans hold the key: cool very quickly to prevent crystals from forming.

Planetary cores aquatic

Uranus and Neptune also bring their extravagant droplet. We do not know their internal structure, but it is now generally accepted that have three layers: an atmosphere of hydrogen and helium, a cloak-possibly liquid water, ammonia and methane, and a nucleus with the same composition to which we must add a set rocky. Other scientists are advocating a model of two layers: an extremely dense atmosphere with a 50% water and a rocky core.

We are facing one of the great mysteries of planetology and assumptions soar. Some scenarios suggest even the existence of an ocean superheated located 8,000 km deep.

For its part, the interior of Titan may be composed in part by ice at different pressures and a layer of liquid water. Yet, in our neighbourhood space, the neighbor who takes the palm is certainly Mars.

Million years ago, the arid and dry Red Planet was a very different place we know today. Not only was warmer and more dense atmosphere, but the water ran by its surface. For the Ares Vallis was circulated friolera of 1,000 million cubic meters per second, an amount that leaves nothing in the 300,000 Amazon or the impressive 60 million from the large waterfall that was formed at the opening of the Strait of Gibraltar and that it filled Today is the Mediterranean after this was dry 5.5 million years ago.

Planetology Some even believe that Mars was a big ocean. With 65 million cubic meters and 1,700 meters deep media, the assumption Oceanus Borealis could cover the plains of the northern third of the planet and coexist with a huge South Pole.