|NASA Photo ID||ISS052-E-63378|
|Time taken||19:20:05 GMT|
4928 x 3280 pixels 720 x 480 pixels 4928 x 3280 pixels 640 x 426 pixels
|Nikon D4 Electronic Still Camera|
|4928E: 4928 x 3280 pixel CMOS sensor, 36.0mm x 23.9mm, total pixels: 16.6 million, Nikon FX format|
|4928 pixels||3280 pixels||No||No||NASA's Earth Observatory web site||Download Image|
|720 pixels||480 pixels||Yes||No||NASA's Earth Observatory web site||Download Image|
|4928 pixels||3280 pixels||No||No||Download Image|
|640 pixels||426 pixels||No||No||Download Image|
An astronaut took this photograph of the Aurora Australis in August 2017. At the time, the International Space Station was moving over the southern Indian Ocean towards the Great Australian Bight and Melbourne, Australia. Click here to see a video of the flight over the aurora.
Auroras are created in the upper atmosphere when the solar wind (a stream of charged particles emitted by the Sun) interacts with the Earth's protective magnetic field. Charged particles within the magnetosphere are accelerated down field lines toward the ionosphere, where they collide with different gases (particularly oxygen and nitrogen) and emit light as a reaction. Auroras often appear as neon green, purple, yellow, or red, depending on the gas molecules being excited. Green, for example, indicates collisions with oxygen.