Apr 25, 2016
The role of color perception
Human vision relies on what is known as trichromacy, the method which allows the mixing of just three fixed wavelengths of light at certain intensities into the multitudes of shades that color the world we see. This is because the human retina, which transmits visual information to the brain, has only three light-absorbing pigments. This is one of the primate kingdom’s benefits since most other animal species are hamstrung with dichromacy, which limits their vision to the mix of just two colors. There are exceptions. A few nocturnal animals have only one color-absorbing pigment, while some fish, birds, and even reptiles actually have four, which gives them the ability to detect ultraviolet light. Not so with humans.2
True enough, some studies have suggested that two-to-three percent of women are born possessing four independent color-informative channels or cone cells in their eyes, which enable them to see a much greater variety of color combinations. Whether they can actually detect the full impact of ultraviolet radiation has not yet been determined, as neither has it been ascertained beyond all doubt that they do possess such a range of color reception. In other words, as of this writing, the studies in question remain somewhat inconclusive.
On the other hand, as Ashton pointed out, people who have had their lens removed were able to see ultraviolet, some of whom described the shade as blue or even downright violet.3 Moreover, youngsters can sometimes detect ultraviolet, but only toward extreme short waves, without having their lens removed, even though requiring special glasses in order to focus the faint images.4
All of the above, however, make for rare and special cases which do not normally apply to the general population. How, then, were our ancient ancestors able to detect proto-Saturn’s ultraviolet hue?
When synthetically-produced ultraviolet light is shone on certain objects, most of us can readily see their change of color and the fluorescent glow they emanate. It is for this reason that black lights, the ultraviolet lamps we mentioned above, are utilized for various scientific and other practical purposes. They are especially useful in medicinal and forensic diagnoses precisely because they allow the scrutiny of important details which are otherwise invisible. They are also used for exhibiting the luminous colors of certain minerals in museum presentations, for idiosyncratic art displays, and special effects during festivities such as Halloween.
Except for the special conditions noted above, however, our present Sun’s display of ultraviolet light does not make itself visible to human eyes. Its radiating orb does not exhibit a purplish hue. This is due to the fact that the light it radiates entails the entire range of the color spectrum. Black lamps, on the other hand, are deliberately made to radiate very little light besides ultraviolet. A similar lack of ordinary light is what enabled the detection of proto-Saturn’s ultraviolet luminosity and its purple orb by ancient man. The violent blast of ultraviolet radiation it emitted through its sudden flare-up would have drastically reduced proto-Saturn’s infrared emission while allowing its enhanced purple brightness to shine through.
Even so, it is doubtful that man was able to perceive all of nature in the iridescent coloration the likes of which is displayed by artificial ultraviolet lights. But, judging by what remains extant of the memories he passed on to his descendants, the purple hue of the proto-Saturnian orb as well as Earth’s atmospheric shell in the period following the flare-up was undoubtedly perceived for long after the event.
Extracted from Chapter 12 of Metamorphic Star, one of the reconstruction books by Dwardu Cardona.