Expedition 64 astronauts, currently on board the International Space Station, recently published several impressive photos of auroras seen from space, over 400 km above sea level.
They occur when particles from solar storms interact with the gases in our atmosphere. Collisions can cause breathtaking spectacles, where colored lights, red, green, blue, yellow or pink, seem to dance in the sky. The phenomenon also occurs in Mars.
Here on Earth, the best places to see the natural spectacle are close to the Arctic Circle such as Alaska, Canada, Iceland, Greenland, Norway, Sweden and Finland in the Northern Hemisphere, where they are called northern lights. In the southern tip of Tasmania and New Zealand, in the Southern Hemisphere, they are known as southern auroras.
In the photo below, the International Space Station was orbiting 423 km above Romania. The lights in the image are from cities in Sweden and Finland, with the dawn over the horizon. The dark area between the two nations is the Baltic Sea.
This one shows a starry sky over Russia, between Ukraine and Kazakhstan. O Note that the dawn is not directly over the horizon, but hovers in the air at an altitude of 100 km, on the border between our atmosphere and space.
This was not the first time that astronauts registered an aurora from the ISS: NASA maintains a album on Flickr only with photos of the phenomenon. According to the agency, the auroras are "a spectacular sign that our planet is electrically connected to the Sun".