Health

Abortion ban: one more obstacle faced by US servicewomen

Abortion bans enacted across America will be especially painful for women in the US military, one more hurdle they have to face in a man's world where sexual assault and unwanted pregnancies occur more often than in the rest ...

Ophthalmology

Drug treatment for cataracts moves a step closer

A revolutionary new treatment for cataracts has shown extremely positive results in laboratory tests, giving hope that the condition, which currently can only be cured with surgery, could soon be treated with drugs.

Medical research

Powerful new synthetic vaccines to combat epidemics

A new type of vaccine that can be stored at warmer temperatures, removing the need for refrigeration, has been developed for mosquito-borne virus Chikungunya in a major advance in vaccine technology. The findings, published ...

Psychology & Psychiatry

Psychological link between conspiracy theories and creationism

Ask a three-year-old why they think it's raining, and she may say "because the flowers are thirsty." Her brother might also tell you that trees have leaves to provide shade for people and animals. These are instances of teleological ...

Diseases, Conditions, Syndromes

Decrease in sunshine, increase in Rickets

A University of Toronto student and professor have teamed up to discover that Britain's increasing cloudiness during the summer could be an important reason for the mysterious increase in Rickets among British children over ...

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Cloud

A cloud is a visible mass of droplets or frozen crystals suspended in the atmosphere above the surface of the Earth or another planetary body. A cloud is also a visible mass attracted by gravity, such as masses of material in space called interstellar clouds and nebulae. Clouds are studied in the nephology or cloud physics branch of meteorology.

On Earth the condensing substance is typically water vapor, which forms small droplets or ice crystals, typically 0.01 mm in diameter. When surrounded by billions of other droplets or crystals they become visible as clouds. Dense deep clouds exhibit a high reflectance (70% to 95%) throughout the visible range of wavelengths. They thus appear white, at least from the top. Cloud droplets tend to scatter light efficiently, so that the intensity of the solar radiation decreases with depth into the gases, hence the gray or even sometimes dark appearance at the base. Thin clouds may appear to have acquired the color of their environment or background and clouds illuminated by non-white light, such as during sunrise or sunset, may appear colored accordingly. In the near-infrared range, clouds look darker because the water that constitutes the cloud droplets strongly absorbs solar radiation at those wavelengths.

This text uses material from Wikipedia, licensed under CC BY-SA