Seeing Invisible Light

Seeing Invisible Light - Infrared image of asteroid belt around a young star
JWST infrared image of never-before-seen asteroid belts around a star 25 light-years from Earth

In ancient times, people looked up into the night sky in wonder. Without modern light pollution, they could have seen the stars more clearly, but they had only their unaided eyes to see the majestic sky. The first revolutionary change occurred when Galileo made and used an optical telescope. However, he was limited by being able to see only the visible spectrum of light. Today, astronomy involves “seeing” invisible light.

Light is electromagnetic radiation, and our vision can detect only a very narrow range of the electromagnetic spectrum. But astronomers today have instruments that allow them to “see” light frequencies in wavelengths outside the human vision range. Yesterday we discussed two portions of the spectrum invisible to our eyes – radio waves and microwaves. Those frequencies can tell us many things about the universe God created. Today, we will examine more ways of seeing invisible light.

The higher the light frequency, the shorter its wavelength. Microwaves have wavelengths between one meter and one millimeter. The next higher frequency of light has wavelengths below one millimeter, so they are called submillimeter waves. One weakness of optical telescopes is that visible light can’t penetrate clouds of gas and dust in regions where stars are forming, but submillimeter waves can. However, water vapor in our atmosphere absorbs submillimeter waves, so astronomers build observatories for studying them in dry, high-altitude locations such as the mountains in Chile and Hawaii.

We find infrared light at even higher frequencies and, thus, shorter wavelengths. Although we can’t see infrared energy, we can feel it as heat. The James Webb Space Telescope (JWST) leads the revolution in infrared astronomy. Scientists have used infrared sensors to measure the temperature of stars, including our Sun, but the Webb Telescope takes that to a new level. It can detect emerging stars hidden by clouds of dust and gas. The JWST can also observe matter that is only a few degrees above absolute zero. In only its second year, JWST has sent back images that allow us to see space objects we have never seen before.

Just above the infrared frequencies, we find optical light. Optical telescopes have been showing us many features of the universe since Galileo, but they have limitations. Not all objects in space produce optical light. For example, we can only see the planets in our solar system because they reflect the Sun’s light. Also, our atmosphere scatters optical light giving us the blue sky in the daytime and atmospheric blurring of the stars at night. Optical telescopes are usually the only option for amateur sky watchers, but for the sharpest viewing, professional astronomers locate their optical telescopes on tall mountains or in space. The Hubble Space Telescope is the leader in optical astronomy.

Although visible light can tell us much about God’s creation, seeing invisible light has opened a new understanding of how the Creator has produced the elements essential for life. Three types of light have higher frequencies and shorter wavelengths than visible light. Those short wavelengths contain the energy to harm or destroy life, but God has provided the protection we need. We will look at that tomorrow.

— Roland Earnst © 2023

Find more information about this picture at Sace.com.

Infrared-seeking Dog Noses

Infrared-seeking Dog Noses

Touch your nose and then touch your dog’s nose. Notice any difference? Like most mammals, your nose is at the ambient temperature. Your dog’s nose, however, is cold and wet. We have known for a long time that vampire bats have cool patches in their nasal areas that act as heat detectors to help them find warm-blooded prey. Researchers have now found that dogs have a very similar structure. Perhaps infrared-seeking dog noses have the same purpose.

A dog’s nose is packed with sensitive nerves. Researchers say that dogs can detect a warm surface at a distance of five feet (1.5 m). When a warm object is placed near a dog in a cold, dark room, the dog will respond to the object even though there is no visible light in the room. Brain activity goes wild in the area that is connected to the nose.

A friend of mine had a dog that would dig up moles in his yard. The dog would move around with his nose to the ground. Then he would suddenly stop and begin digging. Every time, he would flip out a mole. I told my friend he could make a fortune if he could train ten dogs to do that. Now, at last, I know how the dog did it.

Want to make a fortune? Invent an infrared detector sensitive enough to detect a mole six inches below the surface of the ground. It would be hard to do, but God designed infrared-seeking dog noses so they could find prey that is not visible to our eyes.

— John N. Clayton © 2020

Properties of Light

Properties of LightWhen you open your eyes in the morning, take a minute to thank God that you can see. We should reflect upon how good it is to have light instead of the darkness of night. The properties of light make it unique and special.

I am keenly aware of my gift of sight because of a long association with Glynn Langston, who is blind and manages our outreach to the visually impaired. In my lectures, I frequently refer to Edwin Abbott’s book Flatland to help people understand dimensions and how the spiritual is different from the physical. Glynn was born blind, so he is unable to visualize the concept of a sphere crossing a plane and leaving the outline of a circle. He has been kind about it, but my wife once said to me, “How do you expect a blind man to visualize anything!” Even those of us who can see have trouble understanding the properties of light beyond what meets the eye. Radio waves, gamma rays, X-rays, ultraviolet rays, and infra-red rays are all light!

The properties of light make it difficult to comprehend. The most general definition of light is that it is the energy released when a charge changes momentum. The bundle of energy released is called a photon, and the amount of change in momentum determines the energy of the released light. Even in the visible spectrum for humans, the different colors we see are determined by how much energy the light has. Violet has much more energy than red. Ultraviolet has more energy than violet. X-rays and gamma rays have even more energy, but they are still light. Infrared, and radio waves have lower energies than red. That is why infrared warms you and ultraviolet gives you a sunburn. It is also why radio waves can pass through the walls of your home without causing damage and gamma rays can also pass through things, but they will do significant damage.

In the creation process, there had to be special accommodations for the properties of light coming to Earth from the Sun and from outer space. The ozone layer had to be in place to absorb ultraviolet and avoid damage to life. The eyes of every living thing that uses some form of sight had to be designed to function in the part of the spectrum that fit its diet. Rattlesnakes, for example, have specialized sight organs to see in the infrared. Because they eat rodents whose bodies give off radiation in the infrared, a rattlesnake can see its prey on the darkest night. Nearly every insect sees some part of the spectrum other than the colors visible to humans. That is how a mosquito finds you and how insects navigate at night.

Not every star in the sky gives off the properties of light that are needed for life to exist. Some stars radiate in the X-ray part of the spectrum, and others radiate energies too low to be useful to life. Even our trees and shrubs require light in the green part of the visible spectrum to know when to shed their leaves in preparation for winter. In Job 38-41, God spoke to Job to show His wisdom and design and convince Job of his ignorance. Many of the designs God pointed to are connected to light. “Where is the way where light dwells, and where is the location of darkness?” (38:19) “By what process is light parted which scatters the east wind upon the earth?” (38:24) “How does the eagle seek the prey and see that which is afar off?” (39:29)

The Bible speaks of light that is not produced by the acceleration of an electric charge. The most important of these is described in Matthew 5:14-16: “You are the light of the world … let your light so shine before men that they may see your good works and glorify your Father which is in heaven.” Let those of us who are Christians not only be amazed by God’s design of the properties of light and the world in which we live, but let us also strive to be the light Jesus calls us to be.
— John N. Clayton © 2019

Heat Transfer Design

Heat Transfer Design
During this time when record cold temperatures have covered much of the United States, we should consider the design of heat transfer. One of the evidences for the existence of God is the wisdom built into the physical creation that makes it possible to move energy. God created a system of heat transfer design that is far more complex than most of us realize or can imagine.

The primary source of heat for the surface of our planet is the Sun. The question is how heat from the Sun can travel 93 million miles to Earth through what is essentially a vacuum. Realize that there is no substance between the Sun and us, so the heat can’t travel by contact. Atoms are constructed in such a way that they release excess energy by generating small energy packets called photons. Photons from the Sun carry the energy to Earth.

Photon particles are very strange. They have an electric property and a magnetic property, so they are called electromagnetic radiation. Photons have no thickness. They are two dimensional, vibrate with a frequency, and can exist only if they are moving. If you stop a photon, it disappears, and its energy is absorbed by whatever it struck.

Because photons are particles, they can travel across the vacuum of space from the Sun to the Earth. Their vibration frequency determines how we perceive them. We have different names for the frequencies. Xrays, gamma rays, ultraviolet, infrared, radio waves, and visible light are different only in their frequencies. The higher the frequency, the more energy is involved. Gamma rays have a much higher frequency than visible light, so they pack more energy.

Everything radiates some energy, even our bodies, but this is just one way heat is transferred. Besides radiation, heat transfer design also involves conduction and convection. We take for granted the various ways in which heat is transmitted in and around us, but the complexity of heat transfer design is amazing. It is that design which allows us to exist on this planet. We will look at the other two heat transfer methods tomorrow.
–John N. Clayton © 2019