OSIRIS-REx mission explains Bennu's mysterious particle events

Shortly after NASA's OSIRIS-REx spacecraft arrived at asteroid Bennu, an unexpected discovery by the mission's science team revealed that the asteroid could be active, or consistently discharging particles into space. The ...

Jelly invention can heal itself like human skin

Scientists from The Australian National University (ANU) have invented a new jelly material that mimics biological matter such as skin, ligaments and bone, and which is very strong, self-healing and able to change shape.

Rural decline not driven by water recovery

New research from the University of Adelaide has shown that climate and economic factors are the main drivers of farmers leaving their properties in the Murray-Darling Basin, not reduced water for irrigation as commonly claimed.

New eDNA tool research helps scientists find deep sea corals

Curtin University researchers have developed a promising new toolkit for monitoring threatened coral ecosystems by analyzing environmental DNA (eDNA) extracted from waters off the coast of the Cocos (Keeling) Islands.

New projection: Faster rising seas forecast in South Florida

New scientific projections released Wednesday predict that ocean levels will rise even faster than previously forecast over the next four decades in low-lying southeastern Florida, which is already prone to frequent flooding ...

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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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