by APOD Robot » Sun Nov 20, 2022 5:07 am
Airglow Ripples over Tibet
Explanation: Why would the sky look like a giant target?
Airglow. Following a giant thunderstorm over
Bangladesh in late April, giant circular ripples of glowing air appeared over
Tibet,
China, as
pictured here. The unusual
pattern is created by atmospheric
gravity waves, waves of alternating air pressure that can grow
with height as the air thins, in this case about 90-kilometers up. Unlike
auroras powered by collisions with energetic charged particles and seen at high latitudes,
airglow is due to
chemiluminescence, the production of light in a chemical reaction. More typically seen near the horizon,
airglow keeps the night sky from ever being
completely dark.
[url=https://apod.nasa.gov/apod/ap221120.html] [img]https://apod.nasa.gov/apod/calendar/S_221120.jpg[/img] [size=150]Airglow Ripples over Tibet[/size][/url]
[b] Explanation: [/b] Why would the sky look like a giant target? [url=https://earthobservatory.nasa.gov/images/147122/aurora-meet-airglow]Airglow[/url]. Following a giant thunderstorm over [url=https://en.wikipedia.org/wiki/Bangladesh]Bangladesh[/url] in late April, giant circular ripples of glowing air appeared over [url=https://en.wikipedia.org/wiki/Tibet]Tibet[/url], [url=https://en.wikipedia.org/wiki/China]China[/url], as [url=https://www.flickr.com/photos/jeffdai/14845763849/]pictured here[/url]. The unusual [url=http://www.theatlantic.com/technology/archive/2014/04/a-bullseye-in-the-sky-over-texas/360705/]pattern is created by[/url] atmospheric [url=http://www.nasa.gov/multimedia/imagegallery/image_feature_484.html]gravity waves[/url], waves of alternating air pressure that can grow [url=https://climatekids.nasa.gov/whats-in-the-atmosphere/]with height[/url] as the air thins, in this case about 90-kilometers up. Unlike [url=https://apod.nasa.gov/apod/ap221009.html]auroras[/url] powered by collisions with energetic charged particles and seen at high latitudes, [url=https://apod.nasa.gov/apod/ap220313.html]airglow[/url] is due to [url=https://www.atoptics.co.uk/highsky/airglow2.htm]chemiluminescence[/url], the production of light in a chemical reaction. More typically seen near the horizon, [url=https://en.wikipedia.org/wiki/Airglow]airglow[/url] keeps the night sky from ever being [url=https://apod.nasa.gov/apod/ap200408.html]completely dark[/url].
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