by APOD Robot » Mon Nov 15, 2021 5:05 am
Light Pillar over Volcanic Etna
Explanation: What happening above that volcano? Something very unusual -- a volcanic
light pillar. More typically, light pillars are caused by sunlight and so appear as a bright column that extends upward above a rising or setting
Sun. Alternatively, other light pillars --
some quite colorful -- have been recorded above street and house lights. This light
pillar, though, was illuminated by the red light emitted by the glowing magma of an
erupting volcano. The volcano is
Italy's
Mount Etna, and the
featured image was
captured with a single shot a few hours after sunset in mid-June. Freezing temperatures above the volcano's
ash cloud created
ice-crystals either in
cirrus clouds high above the volcano -- or in condensed water vapor expelled by
Mount Etna. These
ice crystals -- mostly
flat toward the ground but fluttering -- then reflected away light from the
volcano's caldera.
[url=https://apod.nasa.gov/apod/ap211115.html] [img]https://apod.nasa.gov/apod/calendar/S_211115.jpg[/img] [size=150]Light Pillar over Volcanic Etna[/size][/url]
[b] Explanation: [/b] What happening above that volcano? Something very unusual -- a volcanic [url=https://en.wikipedia.org/wiki/Light_pillar]light pillar[/url]. More typically, light pillars are caused by sunlight and so appear as a bright column that extends upward above a rising or setting [url=https://solarsystem.nasa.gov/solar-system/sun/by-the-numbers/]Sun[/url]. Alternatively, other light pillars -- [url=https://apod.nasa.gov/apod/ap181024.html]some[/url] [url=https://apod.nasa.gov/apod/ap160208.html]quite[/url] [url=https://apod.nasa.gov/apod/ap131218.html]colorful[/url] -- have been recorded above street and house lights. This light [url=https://www.atoptics.co.uk/halo/pillar.htm]pillar[/url], though, was illuminated by the red light emitted by the glowing magma of an [url=https://youtu.be/z01KTFhA34o]erupting volcano[/url]. The volcano is [url=https://en.wikipedia.org/wiki/Italy]Italy[/url]'s [url=https://en.wikipedia.org/wiki/Mount_Etna]Mount Etna[/url], and the [url=https://www.giancarlotine.it/fotografia-di-paesaggio/foto-gallery-etna/]featured image[/url] was [url=https://www.atoptics.co.uk/fza263.htm]captured with a single shot[/url] a few hours after sunset in mid-June. Freezing temperatures above the volcano's [url=https://apod.nasa.gov/apod/ap190512.html]ash cloud[/url] created [url=https://www.atoptics.co.uk/halo/platcol.htm]ice-crystals[/url] either in [url=https://scool.larc.nasa.gov/GLOBE/cirrus.html]cirrus clouds[/url] high above the volcano -- or in condensed water vapor expelled by [url=https://apod.nasa.gov/apod/ap030416.html]Mount Etna[/url]. These [url=https://www.atoptics.co.uk/halo/lpil.htm]ice crystals[/url] -- mostly [url=https://mrbosscat.com/wp-content/uploads/2021/03/Cat-lying-flat-on-stomach-1536x864.jpg]flat toward the ground[/url] but fluttering -- then reflected away light from the [url=https://youtu.be/gbRdvpTdQdI]volcano's caldera[/url].
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