fucking rainbows, how do they work
My first reaction to this video was you have got to be fucking kidding me, but my second was wow, this is really sad.
In an age where elementary-school curricula are often circumscribed by âReligious Freedom,â air quotes intentional, it is not actually all that surprising that many people appear to possess the same understanding of basic scientific principles as a sackful of doorknobs. The womanâs position in the video represents ignorance compounded by paranoia, and it looks like just astonishing levels of stupid, but I donât think it's helpful to automatically write this sort of thing off as âwow what a dumbass.â
(There are some instances of internet stupidity which I think can be safely put down to âthis person is actually an idiot,â some of which can be extended to âthis person is a criminally irresponsible manipulative fearmongering moron who would not be able to identify a fact if it came up and smacked them in the face with a copy of Babyâs First Introduction to the Exciting World of Critical Thinking,â such as the soi-disant Food Babe. Others, like Joseph âLying for Fun and Profitâ Mercola, may not actually be stupid, but they are dangerous.)
So instead of just pointing and laughing at the lady who thinks government conspiracies are responsible for rainbows appearing in the spray from her garden hose, Iâm going to explain what is responsible for rainbows instead. Itâs not under the control of any government organization in all the world, not even the shadowy cabals lurking in Washington DC to hush up McCarthyist alien illuminati chemtrails.
If youâve ever seen one of those cut-glass suncatcher thingies hanging in a window on a sunny day, you already know that they give off lots and lots of little tiny rainbow-colored points of light. The suncatcher glass is doing the same thing as droplets of water in the air do: it is bending, or refracting, the sunlight that enters it. Since sunlight is made up of lots of different colors of light which have different wavelengths, and since each wavelength is refracted at a slightly different angle, the light passing through the prism is dispersed into individually visible bands. Think of the famous Pink Floyd poster.
If you stand with the sun behind you, looking at water droplets in the air--raindrops, or the spray from a waterfall, or even the spray from your garden hose or sprinkler--you will see at least part of an arc of these bands of color. Sunlight hitting the water droplets is partly reflected back off the surface, but part of it enters the drop. Water, like the glass of the suncatcher, bends light, so when it enters the drop the different wavelengths that make up the light are dispersed into the individual colors of the spectrum. Most of this refracted light bounces off the back of the raindrop, and as it passes out of the front of the drop itâs bent a second time, heading back out at about a 42 degree angle from where it went in. Hereâs a page with diagrams, and hereâs a picture from the Wiki entry showing the spectrum more clearly.
Rainbows, like beauty, are in the eye of the beholder: theyâre a function of your position with regards to the sun and the water droplets. Someone standing at a different position from you will not see the exact same rainbow you are seeing; and you cannot ever see a rainbow side-on. This is because of the angle at which the light is refracted from the raindrops. The best explanation of this Iâve come across is here: with the sun behind you, so that your shadow stretches out directly in front of you, the axis of the sunlight follows a line from your eye to your shadowâs head. Now imagine a line running at a 40 to 42 degree angle from that line, beginning at the level of your eye. This second line describes a cone, centered on the axis of the sunlight. Where raindrops or mist intersect the 40-42 degree arc, you will see the colors of the rainbow. Since the ground tends to get in the way of the bottom of the arc, rainbows seen from ground level arenât going to be circular, but if youâre up high enough--like in a plane, or on top of a super tall building--itâs possible to see the whole thing. When the sun is low in the sky, its rays are closer to horizontal, so you can see almost half the whole arc of the rainbow instead of just the top edge of it.
Hereâs Descartesâ sketch of this whole angle business. Only the little dude with the sword is able to view the rainbow; you would not be able to see it from the POV of this drawing.
So no, the government isnât putting anything in your water to make it show you pretty rainbows in the spray from your garden hose. (I mean, okay, sure, if they put a bunch of salt or something in there so the refractive index of the water changed a bit, the specific characteristics of the rainbow would be altered, but itâd still show up.) What youâre seeing is good old-fashioned motha fuckin optics, and I think thatâs more than cool enough without conspiracies thrown in.