Aurora Astern
Credit:
STS-68 Crew,
NASA
Sailing
upside down, 115
nautical
miles above Earth, the crew of the
Space Shuttle Endeavour
made this spectacular time exposure of the southern
aurora (aurora australis) in October of 1994.
Aurora,
also known as the northern and southern lights,
appear as luminous bands or streamers of light
which can extend to altitudes of 200 miles.
They are typically visible from the Earth's surface at high latitudes and
are triggered by high energy particles from the Sun.
The delicate colors are caused by energetic electrons colliding with
oxygen and nitrogen molecules in the upper atmosphere.
In this picture, the rear
structure of the shuttle Endeavour is in the foreground with
the vertical tail fin pointed toward Earth.
Star trails
are the short streaks above Earth's horizon.