The Soviet Union and USA are pioneers in lunar explorations. However, America’s early missions to reach the Moon either failed or met with little success though they had strong scientific objectives.
After a series of embarrassing failures, the last three spacecraft of the Ranger series – Ranger 7, Ranger 8 and Ranger 9— worked out as planned. All the three returned with high resolution photographs of the Moon. The quality of the photographs increased as the spacecraft moved closer to the Moon. The images showed craters, with the last images displaying craters less than a metre across. These were evidences of the impact origin of the lunar craters. There was no way that volcanism could produce similar craters of all sizes, hundreds of kilometres away from each other.
The US launched five Lunar orbiters that were designed to acquire high resolution images of potential Apollo landing sites after the Ranger Mission. It looked for the views of special craters, rills and mountains, and 100 mm resolution images of much of the entire Moon. This was followed by Lunar Surveyors and the grand Apollo Mission.
Picture Credit : Google
