Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

May 9, 1998

The Water Vapor Channel
Credit: F. Hasler et al., (NASA/GSFC) and The GOES Project

Explanation: What alien planet's bizarre landscape lurks below these fiery-looking clouds? It's only Planet Earth, of course ... as seen on the Water Vapor Channel. Hourly, images like this one (an infrared image shown in false colour) are brought to you by the orbiting Geostationary Operational Environmental Satellites' (GOES) multi-channel imagers. These instruments can produce images at the infrared wavelength of 6.7 microns or about 10 times the wavelength of visible light, recording radiation emitted by water vapour in the upper troposphere. Bright regions correspond to high concentrations of water vapour while dark spots are relatively dry areas. Atmospheric water vapour is invisible to the eye and produced by evaporation from the oceans. Convected upward in the tropical zones it affects the climate by contributing substantially to the greenhouse effect.

Tomorrow's picture: Skylab


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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
&: Michigan Tech. U.