Most ISS images are nadir, in which the center point of the image is directly beneath the lens of the camera, but this one is not. This highly oblique image of northwestern African captures the curvature of the Earth and shows its atmosphere. The Earth's atmosphere is composed of 78 percent nitrogen, 21 percent oxygen and 1 percent other constituents, and it shields us from nearly all harmful radiation coming from the sun and other stars. It also protects us from meteors, most of which burn up before they can strike the planet. Affe
cted by changes in solar activity, the upper atmosphere contributes to weather and climate on Earth. Image Credit: NASA/JPL/UCSD/JSC
