Night Vision

Pilots who need to fly at night are taught the physiology of how human vision adapts to the dark. Specifically, that the light-sensing rods in the periphery of the retina take over in very low light levels, and after about 40 continuous minutes in such conditions, provide a human with the ability to "see" in the dark. Normal daylight "bleaches out" the pigment (rhodopsin) in these rods, making them insensitive to subtle low light signals. For that reason, pilots are taught that any interruption of the dark during this 40 minute period will "reset" the rods and prolong the time needed to develop night vision; they are warned to avoid any light source for fear they will blind themselves in night conditions while flying.



Maybe those of us who journey to the dark side from time to time can use this as a reminder that we have to stay in the dark for a period to be able to appreciate that, in fact, we can see there too. We can sense light, even at extremely low levels when it is "dark". But only if we are brave enough to trust that if we allow ourselves to stay in the dark, the light will show us what it wants us to see.


[Repost from 9/1/2017]