Fastest Stuff in the Universe: The Electromagnetic Spectrum

What goes at the speed of light? Well, a few different things actually. The Electromagnetic Spectrum is the group of types of radiation that goes at the speed of light. These types pf radiation are also known as waves. When high energy objects move at high speeds through space, they give off these electromagnetic waves. The most unique characteristic of these waves is the way it travels. Electromagnetic Waves are the only waves that do not need a medium, also known as molecules to travel through. They can travel through a vacuum. There are seven types of these waves. The waves all travel at the same velocity (the speed pf light). However, where each type of waves differ is in their wavelength, which affects their frequency and energy. The shorter the wavelength, the higher the frequency and the more energy there is.The waves with the longer wavelength are radio waves, followed by microwaves then infrared waves. Visible waves are next with a shorter wavelength, then ultraviolet rays. X-rays have a shorter wavelength than ultraviolet rays. Finally, coming in with the shortest wavelength, highest frequency, and most energy are gamma-rays.

Infrared waves are low level light that is emitted by objects too cool to radiate visible light. Infrared waves are not visible normally. However, they are visible using special cameras that "see" infrared waves. The wavelength of infrared waves varies between 10e-6 and 10e-3 meters long. The frequency varies between 2.481e14 and 3.171e11 Hz. Infrared waves are used for detecting low level light. Thermal imaging cameras are really infrared wave detectors. these types of cameras are used in many forms. Night vision goggles are infrared light detectors. Also, these cameras are used in telescopes to see through the dust around stars, such as nebulae, and see the stars themselves.

Image from http://missionscience.nasa.gov/ems/07_infraredwaves.html

Another type of waves are gamma-rays. Gamma-rays have the shortest wavelengths, from 5.577e-12 meters and shorter. They have the highest frequency, from 5.376e19 Hz and higher. Gamma-rays are only emitted by the hottest objects in the universe, such as pulsars, neutron stars, supernovas, and the areas around black holes. They are detected on Earth in nuclear explosions, lightning, and radioactive decay. Gamma-rays are used in radiation therapy. Also, they are used to map out galaxies and supernovas. Gamma-rays can even show what molecules on planet's surface are made of.

Image from http://missionscience.nasa.gov/ems/12_gammarays.html

And, as always, a Tagxedo of the seven types of waves:

Introduction information: http://imagine.gsfc.nasa.gov/docs/science/know_l1/emspectrum.html

Information about infrared waves: http://missionscience.nasa.gov/ems/07_infraredwaves.html

Information about gamma-rays: http://missionscience.nasa.gov/ems/12_gammarays.html

Wavelengths and frequencies: http://lectureonline.cl.msu.edu/~mmp/applist/Spectrum/s.htm