We know you wouldn’t expect to read on a science website, but take a look at the picture above – a pre-dawn photo taken by a 62 crew member on a mission to the International Space Station (ISS) in March. .
In this image, when the ISS was flying south of the Alaska Peninsula, the brilliant colors you’re seeing interact in different ways in the Earth’s upper atmosphere, resulting in two completely different atmospheric phenomena in one image Huh.
Really magical to look at, but easily explained with some science.
The first event is the aurora – a bright green, red-tipped event to the left of the image. Auroras are produced when solar-charged particles collide with the Earth’s magnetosphere – a type of protective cloak, where such particles hit our magnetic field.
Mixed with atmospheric gases such as oxygen and nitrogen, particles form the color we know as aurora.
Excited by solar wind, oxygen atoms at the highest altitude release this excess energy as a red glow, while green excited oxygen or nitrogen molecules release energy at lower altitudes.
But the aurora is only part of this particular shot. Moving right to the image above, have a look at the yellow-red band of light just above the curve of our planet. It is called an ‘airglow’, and is more subtle than Aurora, but just cold.
To understand airglow – more specifically nightglow – you need to remember that the night sky is never completely dark, not once you remove light pollution, starlight, and diffuse sunlight Huh.
Instead, atoms produce ’emission’ by being in their excited state. For example, oxygen that is broken during recombination in the day and releases its excess energy in the form of photons at night. The reactions between nitrogen molecules and nitrogen and oxygen also contribute to this brightness.
In this case the released photons appear in green, as in this image above, but yellow sometimes occurs on the lower layer (about 80 to 100 kilometers above the Earth’s surface).
Meteors break into this layer of the atmosphere, and release sodium atoms into the air, so it is aptly called the sodium layer; The excited sodium atom will produce a distinct yellow glow.
As a bonus, the sun rising behind the Earth is visible dark blue to the edge of the planet. It is for the same reason that the sky is blue in the daytime – when sunlight collides with molecules in our atmosphere, blue light (one of the shortest wavelengths) is scattered, while other colored light is mostly through Consists of.
We told you, absolutely magical.