Ultraviolet Earth from an Observatory on the Moon
Which planet is this?
Earth.
The featured false color picture shows how the Earth shines in
ultraviolet
(UV) light.
The image is historic because it was
taken from the surface of the Moon
by humanity's
first lunar observatory.
(Another is
operating now.)
Although very little
UV light
is transmitted through the
Earth's atmosphere, what sunlight does make it through might cause a
sunburn.
The part of the Earth facing the
Sun
reflects much UV light,
but perhaps more interesting is the side facing away from the Sun.
Here bands of UV emission are the result of
auroras and are caused by
charged particles expelled by the Sun.
Other planets showing auroras in the UV include
Mars,
Saturn,
Jupiter, and
Uranus.