Starship Asterisk*

[youtube]https://www.youtube.com/watch?v=vdXnZavTDTg[/youtube]

Reminds me of when I was on a boat, in the twilight, after a day on Stromboli. I was looking toward that island's red glowings of hot lava, in the dusk, but then I was startled to see, in addition, sharp pinpricks of blue light, usually near those red patches. Took me quite a while to figure out what THAT mysterious phenomenon could possibly be caused by!

[url=https://apod.nasa.gov/apod/ap180710.html] [img]https://apod.nasa.gov/apod/calendar/S_180710.jpg[/img] [size=150]Noctilucent Clouds over Paris Fireworks[/size][/url]

[b] Explanation: [/b] It's northern noctilucent cloud season -- perhaps a time to celebrate! Composed of small ice crystals forming only during specific conditions in the upper atmosphere, [url=https://apod.nasa.gov/apod/ap090711.html]noctilucent clouds[/url] may become visible at sunset during late summer when illuminated by sunlight from below. [url=https://en.wikipedia.org/wiki/Noctilucent_cloud]Noctilucent clouds[/url] are the [url=https://weather.com/science/weather-explainers/news/2018-06-28-noctilucent-clouds-earth-highest-clouds-view-northern]highest clouds known[/url] and now established to be [url=https://en.wikipedia.org/wiki/Polar_mesospheric_clouds]polar mesospheric clouds[/url] observed from the ground. Although observed with NASA's [url=http://aim.hamptonu.edu/]AIM satellite[/url] since 2007, much about [url=http://science.nasa.gov/science-news/science-at-nasa/2003/19feb_nlc/]noctilucent clouds[/url] remains unknown and so a [url=http://adsabs.harvard.edu/abs/2017JASTP.162..116V]topic of active research[/url]. The [url=https://www.youtube.com/watch?v=FB4IzOiaXPs]featured time-lapse video[/url] shows expansive and rippled [url=https://www.livescience.com/44815-night-shining-clouds-become-more-common.html]noctilucent clouds[/url] wafting over [url=https://www.youtube.com/watch?v=YPMOce2VdKQ]Paris[/url], [url=https://en.wikipedia.org/wiki/France]France[/url], during a post-sunset fireworks celebration on [url=https://en.wikipedia.org/wiki/Bastille_Day]Bastille Day[/url] in 2009 July. This year, [url=http://spaceweathergallery.com/nlc_gallery.html]several locations[/url] are already [url=https://apod.nasa.gov/apod/ap180707.html]reporting[/url] especially [url=https://apod.nasa.gov/apod/ap140731.html]vivid display[/url]s of noctilucent clouds.


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