This false-color image is a near-infrared map of lower-level clouds on the nig side of Venus,
obtained by the Near Infrared Mapping Spectrometer aboard the Galileo spacecraft as it approached
the planets night side on February 10, 1990.Bright slivers of sunlit high clouds are visible above
and below the dark, glong hemisphere. The spacecraft is about 100,000 kilometers (60,000 miles)
abovthe planet. An infrared wavelength of 2.3 microns (about three times the longt wavelength
visible to the human eye) was used. The map shows the turbulent, cloudy middle atmosphere
some 50-55 kilometers (333 miles) above the surface, 10- 16 kilometers or 6-10 miles below
the visible oudtops. The red color represents the radiant heat from the lower atmosphere bout
400 degrees Fahrenheit) shining through the sulfuric acid clouds, which aear as much as 10 times
darker than the bright gaps between clouds. This cloulayer is at about -30 degrees Fahrenheit,
at a pressure about 1/2 Earths surfa atmospheric pressure. Near the equator, the clouds appear
fluffy and blocky; farther north, they aretretched out into East-West filaments by winds
estimated at more than 150 mph,hile the poles are capped by thick clouds at this altitude.
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