Explanation:
Why did an acidic haze spread across Venus?
The unusual clouds were discovered last July by
ESA's robotic
Venus Express
spacecraft currently orbiting
Venus.
The bright and smooth
haze was found by Venus Express to be rich in
sulfuric acid, created when an unknown process lifted water vapor and
sulphur dioxide
from lower levels into
Venus' upper atmosphere.
There, sunlight broke these molecules apart and some of them recombined into the
volatile sulfuric acid.
Over the course of just a few days last July, the smooth acidic clouds spread from the
South Pole of Venus across half the planet.
The above false-color picture of Venus was taken last July 23rd in
ultraviolet light,
and shows the unusual haze as relatively smooth regions across the image bottom.
The cause of the dark streaks in the clouds is also not yet understood and is being researched.
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