NASAさんのインスタグラム写真 - (NASAInstagram)「Aurora, meet airglow 🤩 ⁣ Two of Earth’s most colorful upper atmospheric phenomena, aurora and airglow, met just before dawn in this March 16 photo shot by an astronaut on the International Space Station (@iss).⁣ ⁣ Wavy green, red-topped wisps of aurora borealis appear to intersect the muted red-yellow band of airglow as the station passed just south of the Alaskan Peninsula. The rising Sun, behind Earth’s limb at the time of this photo, adds a deep blue to the horizon. Light from cities in British Columbia and Alberta, Canada, joins starlight to dot the early morning skyscape.⁣ ⁣ Though they appear at similar altitudes, aurora and airglow are produced by different physical processes. Airglow is the emission of light from chemical interactions between oxygen, nitrogen, and other molecules in the upper atmosphere. Auroras, on the other hand, stem from interactions between solar energy and Earth’s magnetic field. ⁣ ⁣ Credit: NASA⁣ Caption: Alex Stoken, @nasajohnson⁣ ⁣ #airglow #aurora #earthatnight #nasa #atmosphere」8月19日 6時08分