Related topics: planets · mars · water · nasa · earth

'Liquid forensics' could lead to safer drinking water

Ping! The popular 1990 film, The Hunt for Red October, helped introduce sonar technology on submarines to pop culture. Now, nearly 30 years later, a team of scientists at the University of Missouri is using this same sonar ...

Sliding along on water

Machine bearings are usually lubricated with various oils. But today large quantities of these oils still end up in the environment. The Fraunhofer Institute for Mechanics of Materials IWM has developed a method which will ...

NASA will fly a drone to Titan to search for life

For its next mission in our solar system, NASA plans to fly a drone copter to Saturn's largest moon Titan in search of the building blocks of life, the space agency said Thursday.

A new 'golden' age for electronics?

One way that heat damages electronic equipment is it makes components expand at different rates, resulting in forces that cause micro-cracking and distortion. Plastic components and circuit boards are particularly prone to ...

Meteors help Martian clouds form

How did the Red Planet get all of its clouds? CU Boulder researchers may have discovered the secret: just add meteors.

Exomoons may be home to extra-terrestrial life

Moons orbiting planets outside our solar system could offer another clue about the pool of worlds that may be home to extra-terrestrial life, according to an astrophysicist at the University of Lincoln.

Seeing inside superfog

While prescribed fires are common tools in wildland management, a combination of smoke and fog, known as superfog, has in some cases crossed over major roadways, leading to multicar pileups and fatalities in visibility of ...

TSU physicists are investigating the effects of radiation on DNA

Scientists from TSU's Laboratory of Experimental High Energy Physics and their colleagues from the University of Bordeaux are studying new ways of modeling the effects of low doses of radiation at the cellular level. For ...

How Venus and Mars can teach us about Earth

One has a thick poisonous atmosphere, one has hardly any atmosphere at all, and one is just right for life to flourish – but it wasn't always that way. The atmospheres of our two neighbours Venus and Mars can teach us a ...

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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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