The Enigma : LIGHT

While thumbing through an Oct. 2001 issue of National Geo. I came across a most interesting article on the Subject of Light. As an amateur astronomer the phenomenon of light has always intrigued me. As in the fact when I have captured M-81 & 82 in my EP's xhairs, knowing I am essentially looking back in time, in this case some 17 million years. Traveling around 669 million mph. for millions of years just now reaching my exit pupil.. Wow!
Light in all its forms---visible & invisible saturates the Universe. Scientists in astrophysics don't fully understand what light is, a wave? a particle? both?
Usually, though, we don't see light, we merely see WITH it.
The color red is just the brain's interpretation of a specific wavelength of light with crests approx. 700 nanometers apart. Light is best understood as a wave when it moves through space..and as a particle of energy, or photon when it encounters the light-sensitive cells in our retina with is dense mat of rods & cones. this triggers neural impulses to the brain. Light is now used for everything from lazer eye surgery to telephone fiber-optics. Lazers are liken to using a mag. glass on a sunny day and compressing a lot of light's energy onto a very small point. Here we come to one of the mysteries of light, it has no volume, and photons have no charge, so in the process of being concentrated into a very small space, they don't repulse each other as neg.charged electrons do. So in this manner a single fiber of optical thread can transmit ten million phone converstions at once...
I have only touched the tip of the ice-b... when it comes to light, it's properties & uses, (and future value it holds beyond our imagination) * Glad to share this with you.. and here is a Solar image to "Hold on to" John M

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Part II. A few more interesting points on the subject of Light I thought you would enjoy.. I mentioned in the above thread that light reaching our eye piece emitted from a distant Galaxy like M-82 took around 15 Million years to arrive. Our nearest star the Sun, the duration is a mere 8 minutes. The term Light Year is a unit of distance (about six trillion miles) In theory if you could be the photon that traveled that distance, you'd experience no time, the 17 million year journey would be instantaneous, remember what Einstein said, once you attain the speed of light time ceases.. To see long stretched-out radio waves, we would have to have Huge eyes, like satellite dishes.. we see only a thin slit of what is really there.. we are blind to most wavelenghts of light, including long radio wave that I have just mentioned, also, damaging shortwave radiation like ultaviolet, X-rays & gamma rays. So our Visible spectrum is from 400 to 750 nanometers..violet to deep red. When Placing a green lens over your eye it absorbs all visible wavelengths of light except those in the middle range of the visible spectrum. the GREEN energy is transmitted to the brain.
Shadows.. Ever wonder about shadows? On a bright sunny day a telephone pole will cast a tack sharp straight shadow onto the sidewalk/street, if you notice, inside the shadow area you can still see things, pebbles, painted lines that run through it, the reason is the shadow is filled with reflected light from the sky (atmosphere). On the moon when the Lunar rover or Apollo astronaut cast a shadow it is completely black, you no longer could see any pebbles or rocks. You would have to illuminated the shadowy darkness with a flashlight...(no atmosphere on the Moon)).. Lastly this evening I will leave you with this, next time you are lucky to view a rainbow, watch for something that usually eludes most observers.. a faint second rainbow (all rainbows appear in pairs) a parallel double that reveals its colors in reverse order.. Clear nights.. John M. in OR. PS. Here is a picture I took this summer in the "Painted Hills" near Prineville OR. Wonder what color the hills really are!

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