The Electromagnetic Spectrum: All Sorts of Light!
There are many different types of energy that come from the Sun. All of the types of energy travel in waves with different wavelengths (the distance between wave tops). All types of energy are part of the electromagnetic spectrum. The energy is called electromagnetic because the waves have electrical and magnetic features. The spectrum usually is divided into these seven parts:
These waves are used to bring you the tunes from your favorite radio station, but they are also a type of radiation from the Sun with long wavelengths.
Microwaves have a slightly smaller wavelength than radio waves. Microwaves can be used to study the Universe, communicate with satellites, and cook popcorn.
Infrared radiation has wavelengths longer than visible radiation and shorter than microwave radiation. Instruments on satellites that detect plants, rock types, and characteristics of the atmosphere use infrared radiation.
This is the part of the electromagnetic spectrum that humans are able to see. It includes all of the colors of the rainbow which, when combined, make white light. Within the spectrum of visible light, red light travels in broad waves while violet light travels in smaller waves.
With slightly more energy than the violet end of the visible light spectrum, most ultraviolet radiation (UV) from the Sun is blocked by Earth's atmosphere, but some makes it through. UV radiation helps plants grow and humans make vitamin D in their bodies. However, too much UV can cause sunburns, skin cancer, cataracts, and can damage plants too.
Because x-rays have short wavelengths and more energy than visible light, they travel through skin, tissue and organs but bounce off hard bone. That's how doctors use them to take photographs of bones.
Gamma rays have the shortest wavelengths of all types of radiation!