Nasa shares stellar image of faint airglow in Earth's atmosphere

Nasa has shared an image of Earth’s “airglow” captured from the International Space Station (ISS), showing the planet wrapped in vivid orange hues created by the atmospheric phenomenon.In a post on Instagram, the space agency shared the photograph taken by French astronaut Sophie Adenot. The image shows a glowing orange band encircling Earth as seen from orbit.“In this image of Earth from the @ISS, Earth appears to be bathed in orange light,” Nasa wrote. “This is due to a phenomenon called airglow, where molecules in the upper atmosphere release energy after being excited by radiation from the Sun. This glow can be a variety of colors, including red, green, purple, and yellow.”Explaining the phenomenon further, Nasa said airglow is constantly present throughout Earth’s atmosphere but is usually too faint to be visible to the naked eye from the ground. “Airglow is constantly shining throughout Earth’s atmosphere, but it is so dim that it can only be seen in orbit or by a sensitive camera from the ground with dark skies,” it said.What is an Airglow?This phenomenon takes place when the atoms and molecules in the Earth's upper atmosphere release energy that they absorb from the Sun’s radiation.Mainly, this happens when molecules (mostly nitrogen and oxygen) are energized by ultraviolet (UV) radiation from sunlight.As they release that energy, atoms in the lower atmosphere bump into each other and lose energy in the collision. The result is a colorful airglow. It is different from Aurora.Airglow performs functions such as carrying information on the upper atmosphere’s temperature, density, and composition. Simultaneously, it helps trace how those particles move in the region.