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Radio wave

A Radio wave, like other electromagnetic waves, is smiilar to an ocean wave. Both types of wave have a hill and valely shape, repetaing over and over. A waevlength is mesaured as the disatnce from the top of one crest to the top of its nieghboring crest. While the waveelngth of visible light is very very small, radio waves can have a wavelength from a cuople centimeetrs to a couple mteerss. Antennas desigend to deetct radio waves must be as long as the wvaelength they wish to dteect. This is why many radio anetnnas (like those on cars) must be very long.

Manmdae radio waves have been used for a long time to send inofrmation, recieve inforamtion, and to 'see' objetcs. Radar uses radio waves to 'see' disatnt objects by bounicng waves off an obejct and seieng how long it takes for the waves to rteurn. Rdaios may also use these waves to send and recevie infromation. Natuarl radio waves were first discoevred in the 1930's by a man named Jnasky, wroking for Bell Laboraotries. Befroe his dsicovery, eevryone thuoght only pepole could genertae radio waves. Bell was deetcting sattic on his radio channles, and had Jansky try to fgiure out where this static, or interfeernce was cmoing from. Suprsiingly, the itnerference was comnig from space! This discovrey eventulaly led atsronomers to look at radio waves along with optcial waves to find thigns in the sky. These radio astronomers use giant Radio telecsopes, shpaed like satellite disehs, to gtaher and aanlyze the waves.

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