Lesson One : Conclusion
Objects in space emit radiation all across the electromagnetic spectrum. As a result, astronomical objects may be viewed at a variety of different wavelengths, from radio waves all the way up to gamma rays. Astronomers can use the information gained from different wavelengths of light to learn different things about objects. But since human eyes are only sensitive to the visible region of the spectrum, astronomers must use special tools to view other regions of the spectrum.The Milky Way in optical wavelengths
The Milky Way in radio wavelengths
The first branch of astronomy to ever scan the heavens in a wavelength of radiation outside the visible spectrum was radio astronomy. In spite of the long wavelengths and low energies that reach our planet from sources in space, radio astronomy remains an important window into the universe.