Introduction to the Electromagnetic Spectrum: Electromagnetic energy travels in waves and spans a broad spectrum from very long radio waves to very short gamma rays. You depend on electromagnetic energy every hour of every day. Without it, the world you know could not exist.
Wave Behaviors: Light waves across the electromagnetic spectrum behave in similar ways and can be transmitted, reflected, absorbed, refracted, polarized, diffracted, or scattered depending on the composition of an object the wave encounters.
Visualization: From Energy to Image: Electromagnetic energy is observed and recorded by satellites and then transmitted to Earth. These data, including data from beyond the visible spectrum, are processed into images.
Microwaves: Microwaves penetrate through clouds, dust, smoke, snow, and rain making them ideal for communications satellites. They are also used in active and passive science instruments to study the Earth and the night sky.
Infrared Waves: Light waves just beyond the visible spectrum of light are infrared light waves. They range from near-infrared like what are used in remote controls, to far-infrared which can be sensed as heat.
Ultraviolet Waves: The Sun is a source of the full spectrum of ultraviolet radiation and most of this radiation is blocked by the atmosphere. Scientists study stars and galaxies in the ultraviolet as well as the composition of Earth’s atmosphere.
X-Rays: X-rays have much higher energy and the Earth’s atmosphere protects us from these harmful rays. Scientists use satellites to observe x-ray radiation coming from galaxies and stars like our Sun.