Related topics: climate change · earth · climate models · climate · sunlight

How will clouds obscure the view of exoplanet surfaces?

In 2021, NASA's next-generation observatory, the James Webb Space Telescope (JWST), will take to space. Once operational, this flagship mission will pick up where other space telescopes—like Hubble, Kepler and Spitzer—left ...

Ships' emissions create measurable regional change in clouds

A container ship leaves a trail of white clouds in its wake that can linger in the air for hours. This puffy line is not just exhaust from the engine, but a change in the clouds that's caused by small airborne particles of ...

Star formation project maps nearby interstellar clouds

Astronomers have captured new, detailed maps of three nearby interstellar gas clouds containing regions of ongoing high-mass star formation. The results of this survey, called the Star Formation Project, will help improve ...

On the origin of massive stars

This scene of stellar creation, captured by the NASA/ESA Hubble Space Telescope, sits near the outskirts of the famous Tarantula Nebula. This cloud of gas and dust, as well as the many young and massive stars surrounding ...

Coronavirus: Nitrogen dioxide emissions drop over Italy

New data from the Copernicus Sentinel-5P satellite reveal the decline of air pollution, specifically nitrogen dioxide emissions, over Italy. This reduction is particularly visible in northern Italy which coincides with its ...

World's first experimental observation of a Kondo cloud

Physicists have been trying to observe the Kondo cloud quantum phenomenon for many decades. An international research team including a scientist from City University of Hong Kong (CityU) has recently developed a novel device ...

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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