Tuesday, November 17, 2009

Invisible but Real

Before discussing the reality of another portion of the invisible electromagnetic spectrum, I’ll ask my readers to join me on a field trip.

Some of the most memorable field trips with my science classes were visits to the museums of the Franklin/Sterling Hill area of northern New Jersey. At the Sterling Hill Mining Museum we walked through old mine tunnels of eons-old crystallized limestone interlaced with the leftovers of commercial minerals recovered during mining operations of long ago. I recall having a sense of strange reverence while walking through 1800 feet of cool, dark mine shafts in the bowels of the earth. Comparing human history with the age of these rocks, these rocks are about 20,000 times older.

The geological complexity of this area provides us with well over 300 different minerals, several dozen of which are found nowhere else in the world. We considered one room at the Franklin Mineral Museum to be one of the highlights of our visit. In ordinary light, we entered a long room--the fluorescent room--with a fairly ordinary array of rocks displayed behind large glass panels. But these rocks were different. Before us was one of the world’s foremost fluorescent mineral collections.

Upon first entering the “fluorescent room” the guide spoke about the minerals while the visible overhead lights were shining. Ultraviolet (UV) light (invisible wavelengths shorter than visible violet) was also shining on the display. At a given moment, the overhead visible lights were turned off. The many specimens of fluorescent minerals, however, continued to glow with a pleasing variety of different hues and brightness. The 1960s crowd may have called such a display “psychedelic.”

What explains the fluorescence? Electrons in the atoms are forced unnaturally to different “energy levels” by the UV light. As those electrons return to their normal energy levels, they emit visible light of a different wavelength--a visible wavelength this time. J.J. Thomson and other 19th century scientists described moving electrical charges as the source of all electromagnetic radiation. Moving electrons generate oscillating electric fields.

Invisible ultraviolet waves come in various wavelengths and have other effects apart from making certain minerals fluoresce. Some cause sunburn; others are beneficial to the body in measured quantities. Certain wavelengths have a germicidal function. The atmosphere filters out most UV coming from outer space.

Spiritual applications and object lessons abound. In fluorescence, the mineral’s source of energy to emit visible light is outside of itself. This reminds us of a similar term often used in scripture: power. In dozens of scripture passages, the power source for righteous living is outside of ourselves. God the Creator is the external source of the Christian’s power to achieve conversion and lead a righteous life.