Explanation:
The strangest moon in the
Solar System is bright yellow.
This
picture,
an attempt to show how Io would appear in the "true colors" perceptible to the average human eye, was taken in 1999 July by the
Galileo spacecraft that orbited Jupiter from 1995 to 2003.
Io's colors derive from
sulfur and molten
silicate rock.
The unusual surface of Io
is kept very young by its system of
active volcanoes.
The intense
tidal gravity of
Jupiter stretches
Io and damps wobbles caused by Jupiter's other
Galilean moons.
The resulting
friction greatly heats
Io's interior, causing
molten rock to explode through the surface.
Io's volcanoes
are so active that they are effectively turning the
whole moon inside out.
Some of
Io's volcanic lava is so hot it
glows in the dark.
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