Fig1_3 Electromagnetic spectrum

Fig1_3 Electromagnetic spectrum

Fig. 1.3 . Radiation from cosmic objects can be emitted at wavelengths from less than 10-12 m to greater than 104 m, where m denotes meters. The visible spectrum that we see with our eyes is a very small portion of the entire range of wavelengths. Lighter shading indicates a greater transparency of the Earth’s atmosphere to cosmic radiation. It only penetrates to the Earth’s surface at visible and radio wavelengths, respectively represented by the narrow and broad white areas. Electromagnetic radiation at short gamma ray, x-ray and ultraviolet wavelengths, represented by the dark areas, is absorbed in our atmosphere, so the universe is now observed in these spectral regions from above the atmosphere in Earth-orbiting satellites.

Copyright 2010, Professor Kenneth R. Lang, Tufts University