And what country can preserve its liberties if their rulers are not warned from time to time that their people preserve the spirit of resistance? Let them take arms. The remedy is to set them right as to facts, pardon and pacify them. What signify a few lives lost in a century or two? The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants.
Tuesday, December 17, 2019
Saw this exact phenomenon flying into Denver this year. I think it's called a Glory.
It is not parhelia. Sundogs come in pairs,one on either side of the sun. The picture is a pilot's glory. It wasn't until the early 1900s that German physicist Gustav Mie came up with a mathematical formula to explain how water droplets suspended in air can scatter light. As this article from the meteorological journal Bulletin of the American Meteorological Society details, glories are created by the backscattering — that is, the deflection at an angle — of sunlight by tiny droplets of water in the atmosphere. (And by tiny, we mean droplets so small that they're only tens of wavelengths across.)
The size of the rings for different wavelengths of light varies, according to the average diameter of the droplets and their distribution; to see a glory, the viewer has to be directly in between the source of light and the water droplets, which is why glories frequently occur with shadows.But even Mie's math didn't completely explain how glories worked. In the 1980s, Nussenzveig and NASA scientist Warren Wiscombe figured out that much of the light that forms a glory doesn't actually pass through the droplets. Instead, as this 2014 piece in the journal Nature explains, the main cause of a glory is a process called wave tunneling, in which sunlight passes near enough to a droplet to create electromagnetic waves within it. Those waves bounce around inside the droplet and eventually get out, sending out light rays that make up most of the glory that we see. The above is stolen from How Stuff Works. I have seen thousands of glories and some are quite spectacular unlike the picture above.
AKA a pilots rainbow
ReplyDeleteThe alien spacecraft has locked on phasers. Abandon hope.
ReplyDeleteEither that or the Pope is onboard.
DeleteA circular rainbow is pretty startling the first time you see it.
It's a sundog.
DeleteIt is not parhelia. Sundogs come in pairs,one on either side of the sun. The picture is a pilot's glory. It wasn't until the early 1900s that German physicist Gustav Mie came up with a mathematical formula to explain how water droplets suspended in air can scatter light. As this article from the meteorological journal Bulletin of the American Meteorological Society details, glories are created by the backscattering — that is, the deflection at an angle — of sunlight by tiny droplets of water in the atmosphere. (And by tiny, we mean droplets so small that they're only tens of wavelengths across.)
ReplyDeleteThe size of the rings for different wavelengths of light varies, according to the average diameter of the droplets and their distribution; to see a glory, the viewer has to be directly in between the source of light and the water droplets, which is why glories frequently occur with shadows.But even Mie's math didn't completely explain how glories worked. In the 1980s, Nussenzveig and NASA scientist Warren Wiscombe figured out that much of the light that forms a glory doesn't actually pass through the droplets. Instead, as this 2014 piece in the journal Nature explains, the main cause of a glory is a process called wave tunneling, in which sunlight passes near enough to a droplet to create electromagnetic waves within it. Those waves bounce around inside the droplet and eventually get out, sending out light rays that make up most of the glory that we see.
The above is stolen from How Stuff Works. I have seen thousands of glories and some are quite spectacular unlike the picture above.
Pilot's Halo.
ReplyDelete