As I was looking at the sky last evening, I realized that I had not seen any stars in a long time. It is because of all the light pollution generated by our numerous illuminated buildings, street lights, automobiles and electric signs. Cities glow and pulse with light.
So how do I know that stars exist? How many other phenomena am I unaware of because I have only 5 senses with a very limited reach?
An eagle can see a rabbit from two miles away. I also learned that they adjust the curvature of their eyes as they descend to attack so prey is always in sharp focus. Bats navigate by echolocation which is completely alien to us. Vampire bats have proteins in their noses that lead them to food.
Our sense of smell is very rudimentary. Often it stops at pleasant or unpleasant and does not reveal edibility or harmfulness. Elephants’ feet and trunks are sensitive enough to pick up vibrations created by other elephants as far as 10 miles away.
Our hearing is also problematic. We often do not know how to follow it to its source or whether it signals danger or not. Our experience is often limited by the size and distance of the object being heard.
Because we long ago realized that much of the world is hidden from us, we knew we had to build instruments to expand our search abilities and learn the truth. But what is the truth of a star or the truth of a tree for that matter? Still we have to strive to understand that elusive reality.
Microphones and ultrasound devices capture unheard sounds. Smoke detectors can smell fires. Thermometers can measure exact temperatures beyond cold or hot. Litmus paper can tell if a substance is an acid or a base. In 1610 Galileo invented the telescope to examine the Milky Way and its vast collection of stars. He suspected that there existed many more heavenly bodies beyond our galaxy.
Since then telescopes have grown in size and complexity. The Hubble telescope which is suspended high in space is a most productive scientific instrument. It whirls around the earth and takes pictures through the haze of the atmosphere. It is only the size of a bus but it can look back to when the universe was only 3% of its current age. It can spot the dark energy that exists in space.
We have enlarged our horizons and will continue to expand our ability to apprehend and comprehend the world because we have one sense that is truly unlimited, our sense of curiosity.