Light: Going Beyond the Bulb


Caption: In this piece of art, light bulbs were placed in a medical X-ray machine. The artist then added color to the individual light bulbs to create the desired effect. Credit: Dr. Paula Fontaine/

Light is one of those things that we almost inevitably take for granted. In fact, many of us might not realize the extent that we overlook its contributions to our lives, because it’s hard to see – literally — just how much it does.

The light that humans can detect with their eyes is but a mere fraction of the total light out there. Light takes many forms, including radio waves, microwaves, infrared, ultraviolet, X-rays and gamma rays.

Caption: The electromagnetic spectrum includes wavelengths and energies from radio to gamma rays. Illustration: NASA/CXC/M.Weiss

We rely on light — both natural and sources made by humans — to brighten our world. In the form of radio waves and microwaves, light is also used for communication and navigation through cellphones and GPS. Medical tools that use light, including the highest-energy light of X-rays and gamma rays, help us monitor our bodies and attack certain diseases such as cancer.

Caption: We use light for many purposes including some basic ones such as illuminating our way. This image combines eight different photos, each with exposures of 30 seconds, which show car headlights along a highway. In the future, reflected lasers may power more of our headlights, providing a more powerful and energy-efficient (yet still safe) beam that lights our way through the night.

Scientists use instruments on the ground and in space that detect different types of light like infrared to monitor our climate and forecast our weather. Astronomers capture light in all types from the cosmos to understand distant galaxies, to look for signs —> Read More