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Liquid water on exomoons of free-floating planets

The moons of planets that have no parent star can possess an atmosphere and retain liquid water. Astrophysicists at LMU have calculated that such systems could harbor sufficient water to make life possible—and sustain it.

Scientists find carbon-rich liquid water in ancient meteorite

Water is abundant in the solar system. Even beyond Earth, scientists have detected ice on the moon, in Saturn's rings and in comets, liquid water on Mars and under the surface of Saturn's moon Enceladus, and traces of water ...

Ocean currents predicted on Enceladus

Buried beneath 20 kilometers of ice, the subsurface ocean of Enceladus—one of Saturn's moons—appears to be churning with currents akin to those on Earth.

Terahertz waves from electrons oscillating in liquid water

Ionization of water molecules by light generates free electrons in liquid water. After generation, the so-called solvated electron is formed, a localized electron surrounded by a shell of water molecules. In the ultrafast ...

On the line: Watching nanoparticles get in shape

Liquid structures—liquid droplets that maintain a specific shape—are useful for a variety of applications, from food processing to cosmetics, medicine, and even petroleum extraction, but researchers have yet to tap into ...

New material shown to more efficiently desalinate water

By 2025, two-thirds of the world's population could experience a freshwater shortage. To tackle this issue, researchers from the University of Notre Dame have identified a new solvent—an ionic liquid—that improves on ...

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Water

Water is a ubiquitous chemical substance, composed of hydrogen and oxygen, that is essential for the survival of many known forms of life. In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam. Water covers 71% of the Earth's surface. On Earth, it is found mostly in oceans and other large water bodies, with 1.6% of water below ground in aquifers and 0.001% in the air as vapor, clouds (formed of solid and liquid water particles suspended in air), and precipitation. Saltwater oceans hold 97% of surface water, glaciers and polar ice caps 2.4%, and other land surface water such as rivers, lakes and ponds 0.6%. A very small amount of the Earth's water is contained within biological bodies and manufactured products. Other water is trapped in ice caps, glaciers, aquifers, or in lakes, sometimes providing fresh water for life on land.

Water moves continually through a cycle of evaporation or transpiration (evapotranspiration), precipitation, and runoff, usually reaching the sea. Winds carry water vapor over land at the same rate as runoff into the sea. Over land, evaporation and transpiration contribute to the precipitation over land.

Clean, fresh drinking water is essential to human and other lifeforms. Access to safe drinking water has improved steadily and substantially over the last decades in almost every part of the world. There is a clear correlation between access to safe water and GDP per capita. However, some observers have estimated that by 2025 more than half of the world population will be facing water-based vulnerability. Water plays an important role in the world economy, as it functions as a solvent for a wide variety of chemical substances and facilitates industrial cooling and transportation. Approximately 70 percent of freshwater is consumed by agriculture.

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