Astronomy Fundamentals

Time, Waves, and Particles

What are ultraviolet rays?

Ultraviolet rays are electromagnetic waves whose wavelengths range between about 10–8 and 3.5 x 10–7 meters. This is the kind of radiation that causes suntans and sunburns on human skin.


This is a web preview of the "The Handy Astronomy Answer Book" app. Many features only work on your mobile device. If you like what you see, we hope you will consider buying. Get the App