The Civil War had a greater impact on American society in the polity than any other event in the country’s history.
Not really sure what your masking really?
The correct answer should be
<span>It was discovered in the 1960s.
The telescope is at least 300 years older than remote sensing since remote sensing began around the era of airplanes and flying balloons. You don't have to be a scientist which is seen in the military where soldiers do it. Modern remote sensing started in the 60s with the development of satellites and space travel.</span>