What Object Emit Radio Waves?

-- | July 29, 2014

Question:  What objects emit radio waves?  — Chris

Answer:  In fact, all objects that emit energy also emit radio waves.  The term “radio waves” is really just a description of one range of frequencies in the entire spectrum of frequencies that together make up what we call “electromagnetic radiation”.  The range of frequencies in the electromagnetic spectrum that our eyes are sensitive to is what we call “light”.  Radio waves are roughly defined as wavelengths from about one meter to one millimeter, or frequencies from about 300 MHz to 300,000 MHz.  So, any object which radiates energy (including us!) emits that energy across the entire electromagnetic spectrum (though with different intensities as a function of wavelength, dependent upon the amount of energy emitted).  Very high-energy objects, for example, can be seen in high-energy X-rays, or even gamma-rays.

Jeff Mangum