Sunset from the International Space Station
Credit:
Expedition 23 Crew,
NASA
What are these strange color bands being seen from the International Space Station?
The Sun setting through Earth's atmosphere.
Pictured above, a sunset captured last month by the ISS's
Expedition 23
crew
shows in vivid detail many layers of the
Earth's thin atmosphere.
Part of the
Earth experiencing night
crosses the bottom of the image.
Above that,
appearing in deep orange and yellow, is the Earth's
troposphere,
which contains 80 percent of the atmosphere by mass and
almost all of the
clouds in the sky.
Above the troposphere, seen as a light blue band with white clouds, is the
stratosphere, part of the Earth's atmosphere where airplanes fly and some hardy bacteria float.
Above the stratosphere, visible as a darker blue bands, are higher and thinner
atmospheric levels that gradually fade away into the cold dark
vacuum of
outer space.
Sunset is not an uncommon
sight
for occupants of the
International Space Station,
because it can be seen as many as 16 times a day.