"What is the History of Environmental Remote Sensing?"

            Remote Sensing really got its start when the camera was invented in the 1800's.  People first thought of making pictures of the Earth from the sky in the 1840's.  At that time, they attached cameras to hot air balloons and took images in order to make maps.  At one point, someone even placed a small camera on a pigeon in order to take a picture from the sky.  

    Taking pictures from a balloon.                     The view from a pigeon.

           During both World Wars, cameras on airplanes were used to obtain military information.  And until the early 1960s, the aerial photography was really the only way to see large parts of the Earth at one time.  Satellite remote sensing has its roots in the "space race" of the 1950s and 1960s.  Early astronauts took pictures of the Earth from their space capsules, and scientists also attached cameras to early rockets which filmed as they rose into space. 

        
            The first artificial satellite, Russia's Sputnik I,  was launched into space in 1957.  Since then, thousands of satellites have been put into orbit.  Satellites have many different uses.  Some let us communicate better, or allow the military to get information from other countries without putting pilots in danger.  Other satellites have been used to measure the health of the planet.  These devices have revolutionized the way that we look at the Earth and its land, water and atmosphere. 

                                                             Landsat I           

           The first satellite really designed for looking at Earth was a weather satellite, TIROS I, which was placed in orbit in 1960.  TIROS I provided pictures of large weather systems and was the first of many satellites that changed weather forecasting forever.  The first satellite that was designed to look at Earth's surface was Earth Resources Technology Satellite, or ERTS I, launched in 1972.  This satellite, eventually renamed LANDSAT I, was followed by several more LANDSAT satellites.  LANDSATs are still in operation today, and provide a unique view of the Earth by looking at wavelengths of light that cannot be seen by the human eye.  There have been many other Earth observing satellites since TIROS and LANDSAT.  Click on the links below to find out more.             

Sources

http://earthobservatory.nasa.gov/Library/RemoteSensing/remote.html 

http://earth.nasa.gov/history/landsat/landsat.html 

http://www.atmosp.physics.utoronto.ca/people/strong/phy499/section1ohds_02.pdf 

http://www.earth.nasa.gov/history/tiros/tiros.html